draft-ietf-pana-pana-06.txt   draft-ietf-pana-pana-07.txt 
PANA Working Group D. Forsberg PANA Working Group D. Forsberg
Internet-Draft Nokia Internet-Draft Nokia
Expires: April 20, 2005 Y. Ohba (Ed.) Expires: June 29, 2005 Y. Ohba (Ed.)
Toshiba Toshiba
B. Patil B. Patil
Nokia Nokia
H. Tschofenig H. Tschofenig
Siemens Siemens
A. Yegin A. Yegin
Samsung Samsung
October 20, 2004 December 29, 2004
Protocol for Carrying Authentication for Network Access (PANA) Protocol for Carrying Authentication for Network Access (PANA)
draft-ietf-pana-pana-06 draft-ietf-pana-pana-07
Status of this Memo Status of this Memo
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and any of which I become aware will be disclosed, in accordance with and any of which I become aware will be disclosed, in accordance with
RFC 3668. RFC 3668.
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Copyright (C) The Internet Society (2004). All Rights Reserved. Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract Abstract
Extensible Authentication Protocol (EAP) defines a number of This document defines the Protocol for Carrying Authentication for
authentication schemes. Network access authentication requires a Network Access (PANA), a link-layer agnostic transport for Extensible
host to authenticate itself before being authorized for sending and Authentication Protocol (EAP) to enable network access authentication
receiving packets. The Protocol for Carrying Authentication for between clients and access networks. PANA can carry any
Network Access (PANA) is defined in this document. PANA is a authentication method that can be specified as an EAP method, and it
link-layer agnostic carrier for EAP. PANA specifies the can be used on any link that can carry IP. PANA protocol
client-to-network access authentication within the scope of an specification covers the client-to-network access authentication part
overall secure network access framework. of an overall secure network access framework, which additionally
includes other protocols and mechanisms for service provisioning,
access control as a result of initial authentication, and accounting.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1 Specification of Requirements . . . . . . . . . . . . . . 5 1.1 Specification of Requirements . . . . . . . . . . . . . . 5
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 6 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Protocol Overview . . . . . . . . . . . . . . . . . . . . . 8 3. Protocol Overview . . . . . . . . . . . . . . . . . . . . . 9
4. Protocol Details . . . . . . . . . . . . . . . . . . . . . . 10 4. Protocol Details . . . . . . . . . . . . . . . . . . . . . . 11
4.1 Discovery and Handshake Phase . . . . . . . . . . . . . . 10 4.1 Payload Encoding . . . . . . . . . . . . . . . . . . . . . 11
4.2 Authentication Phase . . . . . . . . . . . . . . . . . . . 13 4.2 Discovery and Handshake Phase . . . . . . . . . . . . . . 12
4.3 Authorization Phase . . . . . . . . . . . . . . . . . . . 15 4.3 Authentication and Authorization Phase . . . . . . . . . . 15
4.4 Re-authentication Phase . . . . . . . . . . . . . . . . . 15 4.4 Access Phase . . . . . . . . . . . . . . . . . . . . . . . 18
4.5 Termination Phase . . . . . . . . . . . . . . . . . . . . 17 4.5 Re-authentication Phase . . . . . . . . . . . . . . . . . 19
5. Protocol Design Details and Processing Rules . . . . . . . . 19 4.6 Termination Phase . . . . . . . . . . . . . . . . . . . . 20
5.1 Payload Encoding . . . . . . . . . . . . . . . . . . . . . 19 4.7 Separate NAP and ISP Authentication . . . . . . . . . . . 21
5.2 Transport Layer . . . . . . . . . . . . . . . . . . . . . 20 4.7.1 Negotiating Separate NAP and ISP Authentication . . . 21
5.2.1 Fragmentation . . . . . . . . . . . . . . . . . . . . 20 4.7.2 Execution of Separate NAP and ISP Authentication . . . 22
5.3 Sequence Number and Retransmission . . . . . . . . . . . . 20 4.7.3 AAA-Key Calculation . . . . . . . . . . . . . . . . . 23
5.4 Message Authentication Code . . . . . . . . . . . . . . . 21 5. Protocol Design Details and Processing Rules . . . . . . . . 24
5.5 Message Validity Check . . . . . . . . . . . . . . . . . . 21 5.1 Transport Layer . . . . . . . . . . . . . . . . . . . . . 24
5.6 PANA Security Association . . . . . . . . . . . . . . . . 23 5.1.1 Fragmentation . . . . . . . . . . . . . . . . . . . . 24
5.7 Error Handling . . . . . . . . . . . . . . . . . . . . . . 25 5.2 Sequence Number and Retransmission . . . . . . . . . . . . 24
5.8 Device ID Choice . . . . . . . . . . . . . . . . . . . . . 25 5.3 PANA Security Association . . . . . . . . . . . . . . . . 25
5.9 Updating PaC' Address . . . . . . . . . . . . . . . . . . 26 5.4 Message Authentication Code . . . . . . . . . . . . . . . 27
5.10 Session Lifetime . . . . . . . . . . . . . . . . . . . . 26 5.5 Message Validity Check . . . . . . . . . . . . . . . . . . 28
5.11 Network Selection . . . . . . . . . . . . . . . . . . . 27 5.6 Device ID Choice . . . . . . . . . . . . . . . . . . . . . 29
5.12 Separate NAP and ISP Authentication . . . . . . . . . . 27 5.7 PaC Updating its IP Address . . . . . . . . . . . . . . . 30
5.12.1 Negotiating Separate NAP and ISP Authentication . . 28 5.8 Session Lifetime . . . . . . . . . . . . . . . . . . . . . 30
5.12.2 Execution of Separate NAP and ISP Authentication . . 28 5.9 Network Selection . . . . . . . . . . . . . . . . . . . . 31
5.12.3 AAA-Key Calculation . . . . . . . . . . . . . . . . 29 5.10 Error Handling . . . . . . . . . . . . . . . . . . . . . 32
5.12.4 Re-authentication . . . . . . . . . . . . . . . . . 30 6. PANA Headers and Formats . . . . . . . . . . . . . . . . . . 33
5.12.5 Example Sequence . . . . . . . . . . . . . . . . . . 30 6.1 IP and UDP Headers . . . . . . . . . . . . . . . . . . . . 33
6. Security and Mobility . . . . . . . . . . . . . . . . . . . 32 6.2 PANA Header . . . . . . . . . . . . . . . . . . . . . . . 33
6.1 PANA Security Association Establishment . . . . . . . . . 32 6.3 AVP Header . . . . . . . . . . . . . . . . . . . . . . . . 35
6.2 Mobility . . . . . . . . . . . . . . . . . . . . . . . . . 32 7. PANA Messages, Message Specifications and AVPs . . . . . . . 38
7. PANA Headers and Formats . . . . . . . . . . . . . . . . . . 35 7.1 PANA Messages . . . . . . . . . . . . . . . . . . . . . . 38
7.1 IP and UDP Headers . . . . . . . . . . . . . . . . . . . . 35 7.2 PANA Message ABNF Specification . . . . . . . . . . . . . 38
7.2 PANA Header . . . . . . . . . . . . . . . . . . . . . . . 35 7.2.1 PANA-PAA-Discover (PDI) . . . . . . . . . . . . . . . 40
7.3 AVP Header . . . . . . . . . . . . . . . . . . . . . . . . 37 7.2.2 PANA-Start-Request (PSR) . . . . . . . . . . . . . . . 41
8. PANA Messages, Message Specifications and AVPs . . . . . . . 40 7.2.3 PANA-Start-Answer (PSA) . . . . . . . . . . . . . . . 41
8.1 PANA Messages . . . . . . . . . . . . . . . . . . . . . . 40 7.2.4 PANA-Auth-Request (PAR) . . . . . . . . . . . . . . . 41
8.2 Message Specifications . . . . . . . . . . . . . . . . . . 40 7.2.5 PANA-Auth-Answer (PAN) . . . . . . . . . . . . . . . . 42
8.2.1 PANA-PAA-Discover (PDI) . . . . . . . . . . . . . . . 41 7.2.6 PANA-Reauth-Request (PRAR) . . . . . . . . . . . . . . 42
8.2.2 PANA-Start-Request (PSR) . . . . . . . . . . . . . . . 41 7.2.7 PANA-Reauth-Answer (PRAA) . . . . . . . . . . . . . . 42
8.2.3 PANA-Start-Answer (PSA) . . . . . . . . . . . . . . . 41 7.2.8 PANA-Bind-Request (PBR) . . . . . . . . . . . . . . . 42
8.2.4 PANA-Auth-Request (PAR) . . . . . . . . . . . . . . . 41 7.2.9 PANA-Bind-Answer (PBA) . . . . . . . . . . . . . . . . 43
8.2.5 PANA-Auth-Answer (PAN) . . . . . . . . . . . . . . . . 42 7.2.10 PANA-Ping-Request (PPR) . . . . . . . . . . . . . . 43
8.2.6 PANA-Reauth-Request (PRAR) . . . . . . . . . . . . . . 42 7.2.11 PANA-Ping-Answer (PPA) . . . . . . . . . . . . . . . 43
8.2.7 PANA-Reauth-Answer (PRAA) . . . . . . . . . . . . . . 42 7.2.12 PANA-Termination-Request (PTR) . . . . . . . . . . . 44
8.2.8 PANA-Bind-Request (PBR) . . . . . . . . . . . . . . . 42 7.2.13 PANA-Termination-Answer (PTA) . . . . . . . . . . . 44
8.2.9 PANA-Bind-Answer (PBA) . . . . . . . . . . . . . . . . 43 7.2.14 PANA-Error-Request (PER) . . . . . . . . . . . . . . 44
8.2.10 PANA-Ping-Request (PPR) . . . . . . . . . . . . . . 43 7.2.15 PANA-Error-Answer (PEA) . . . . . . . . . . . . . . 44
8.2.11 PANA-Ping-Answer (PPA) . . . . . . . . . . . . . . . 43 7.2.16 PANA-FirstAuth-End-Request (PFER) . . . . . . . . . 45
8.2.12 PANA-Termination-Request (PTR) . . . . . . . . . . . 43 7.2.17 PANA-FirstAuth-End-Answer (PFEA) . . . . . . . . . . 45
8.2.13 PANA-Termination-Answer (PTA) . . . . . . . . . . . 44 7.2.18 PANA-Update-Request (PUR) . . . . . . . . . . . . . 45
8.2.14 PANA-Error-Request (PER) . . . . . . . . . . . . . . 44 7.2.19 PANA-Update-Answer (PUA) . . . . . . . . . . . . . . 46
8.2.15 PANA-Error-Answer (PEA) . . . . . . . . . . . . . . 44 7.3 AVPs in PANA . . . . . . . . . . . . . . . . . . . . . . . 46
8.2.16 PANA-FirstAuth-End-Request (PFER) . . . . . . . . . 44 7.3.1 Cookie AVP . . . . . . . . . . . . . . . . . . . . . . 48
8.2.17 PANA-FirstAuth-End-Answer (PFEA) . . . . . . . . . . 45 7.3.2 Device-Id AVP . . . . . . . . . . . . . . . . . . . . 48
8.2.18 PANA-Update-Request (PUR) . . . . . . . . . . . . . 45 7.3.3 EAP-Payload AVP . . . . . . . . . . . . . . . . . . . 49
8.2.19 PANA-Update-Answer (PUA) . . . . . . . . . . . . . . 45 7.3.4 Failed-AVP AVP . . . . . . . . . . . . . . . . . . . . 49
8.3 AVPs in PANA . . . . . . . . . . . . . . . . . . . . . . . 45 7.3.5 IP-Address AVP . . . . . . . . . . . . . . . . . . . . 49
8.3.1 MAC AVP . . . . . . . . . . . . . . . . . . . . . . . 48 7.3.6 ISP-Information AVP . . . . . . . . . . . . . . . . . 49
8.3.2 Device-Id AVP . . . . . . . . . . . . . . . . . . . . 49 7.3.7 Key-Id AVP . . . . . . . . . . . . . . . . . . . . . . 49
8.3.3 Session-Id AVP . . . . . . . . . . . . . . . . . . . . 49 7.3.8 MAC AVP . . . . . . . . . . . . . . . . . . . . . . . 50
8.3.4 Cookie AVP . . . . . . . . . . . . . . . . . . . . . . 49 7.3.9 NAP-Information AVP . . . . . . . . . . . . . . . . . 50
8.3.5 Protection-Capability AVP . . . . . . . . . . . . . . 49 7.3.10 Nonce AVP . . . . . . . . . . . . . . . . . . . . . 50
8.3.6 Termination-Cause AVP . . . . . . . . . . . . . . . . 49 7.3.11 Notification AVP . . . . . . . . . . . . . . . . . . 50
8.3.7 Result-Code AVP . . . . . . . . . . . . . . . . . . . 50 7.3.12 Post-PANA-Address-Configuration (PPAC) AVP . . . . . 51
8.3.8 EAP-Payload AVP . . . . . . . . . . . . . . . . . . . 54 7.3.13 Protection-Capability AVP . . . . . . . . . . . . . 52
8.3.9 Session-Lifetime AVP . . . . . . . . . . . . . . . . . 54 7.3.14 Provider-Identifier AVP . . . . . . . . . . . . . . 52
8.3.10 Failed-AVP AVP . . . . . . . . . . . . . . . . . . . 54 7.3.15 Provider-Name AVP . . . . . . . . . . . . . . . . . 52
8.3.11 NAP-Information AVP . . . . . . . . . . . . . . . . 54 7.3.16 Result-Code AVP . . . . . . . . . . . . . . . . . . 52
8.3.12 ISP-Information AVP . . . . . . . . . . . . . . . . 54 7.3.17 Session-Id AVP . . . . . . . . . . . . . . . . . . . 56
8.3.13 Provider-Identifier AVP . . . . . . . . . . . . . . 54 7.3.18 Session-Lifetime AVP . . . . . . . . . . . . . . . . 56
8.3.14 Provider-Name AVP . . . . . . . . . . . . . . . . . 55 7.3.19 Termination-Cause AVP . . . . . . . . . . . . . . . 56
8.3.15 Key-Id AVP . . . . . . . . . . . . . . . . . . . . . 55 8. Retransmission Timers . . . . . . . . . . . . . . . . . . . 58
8.3.16 Post-PANA-Address-Configuration (PPAC) AVP . . . . . 55 8.1 Transmission and Retransmission Parameters . . . . . . . . 59
8.3.17 Nonce AVP . . . . . . . . . . . . . . . . . . . . . 56 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . 61
8.3.18 IP-Address AVP . . . . . . . . . . . . . . . . . . . 56 9.1 PANA UDP Port Number . . . . . . . . . . . . . . . . . . . 61
9. PANA Protocol Message Retransmissions . . . . . . . . . . . 57 9.2 PANA Multicast Address . . . . . . . . . . . . . . . . . . 61
9.1 Transmission and Retransmission Parameters . . . . . . . . 58 9.3 PANA Header . . . . . . . . . . . . . . . . . . . . . . . 61
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . 60 9.3.1 Message Type . . . . . . . . . . . . . . . . . . . . . 61
10.1 PANA UDP Port Number . . . . . . . . . . . . . . . . . . 60 9.3.2 Flags . . . . . . . . . . . . . . . . . . . . . . . . 62
10.2 PANA Multicast Address . . . . . . . . . . . . . . . . . 60 9.4 AVP Header . . . . . . . . . . . . . . . . . . . . . . . . 62
10.3 PANA Header . . . . . . . . . . . . . . . . . . . . . . 60 9.4.1 AVP Code . . . . . . . . . . . . . . . . . . . . . . . 62
10.3.1 Message Type . . . . . . . . . . . . . . . . . . . . 60 9.4.2 Flags . . . . . . . . . . . . . . . . . . . . . . . . 63
10.3.2 Flags . . . . . . . . . . . . . . . . . . . . . . . 61 9.5 AVP Values . . . . . . . . . . . . . . . . . . . . . . . . 63
10.4 AVP Header . . . . . . . . . . . . . . . . . . . . . . . 61 9.5.1 Algorithm Values of MAC AVP . . . . . . . . . . . . . 63
10.4.1 AVP Code . . . . . . . . . . . . . . . . . . . . . . 61 9.5.2 Post-PANA-Address-Configuration AVP Values . . . . . . 63
10.4.2 Flags . . . . . . . . . . . . . . . . . . . . . . . 62 9.5.3 Protection-Capability AVP Values . . . . . . . . . . . 63
10.5 AVP Values . . . . . . . . . . . . . . . . . . . . . . . 62 9.5.4 Result-Code AVP Values . . . . . . . . . . . . . . . . 63
10.5.1 Algorithm Values of MAC AVP . . . . . . . . . . . . 62 9.5.5 Termination-Cause AVP Values . . . . . . . . . . . . . 64
10.5.2 Protection-Capability AVP Values . . . . . . . . . . 62 10. Security Considerations . . . . . . . . . . . . . . . . . . 65
10.5.3 Termination-Cause AVP Values . . . . . . . . . . . . 62 10.1 General Security Measures . . . . . . . . . . . . . . . 65
10.5.4 Result-Code AVP Values . . . . . . . . . . . . . . . 62 10.2 Discovery . . . . . . . . . . . . . . . . . . . . . . . 66
10.5.5 Post-PANA-Address-Configuration AVP Values . . . . . 63 10.3 EAP Methods . . . . . . . . . . . . . . . . . . . . . . 67
11. Security Considerations . . . . . . . . . . . . . . . . . . 64 10.4 Separate NAP and ISP Authentication . . . . . . . . . . 67
11.1 General Security Measures . . . . . . . . . . . . . . . 64 10.5 Cryptographic Keys . . . . . . . . . . . . . . . . . . . 67
11.2 Discovery . . . . . . . . . . . . . . . . . . . . . . . 65 10.6 Per-packet Ciphering . . . . . . . . . . . . . . . . . . 68
11.3 EAP Methods . . . . . . . . . . . . . . . . . . . . . . 66 10.7 PAA-to-EP Communication . . . . . . . . . . . . . . . . 68
11.4 Separate NAP and ISP Authentication . . . . . . . . . . 66 10.8 Liveness Test . . . . . . . . . . . . . . . . . . . . . 69
11.5 Cryptographic Keys . . . . . . . . . . . . . . . . . . . 66 10.9 Updating PaC's IP Address . . . . . . . . . . . . . . . 69
11.6 Per-packet Ciphering . . . . . . . . . . . . . . . . . . 67 10.10 Early Termination of a Session . . . . . . . . . . . . . 69
11.7 PAA-to-EP Communication . . . . . . . . . . . . . . . . 67 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 70
11.8 Livenes Test . . . . . . . . . . . . . . . . . . . . . . 68 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 71
11.9 Mobility Optimization . . . . . . . . . . . . . . . . . 68 12.1 Normative References . . . . . . . . . . . . . . . . . . . 71
11.10 Updating PaC's IP Address . . . . . . . . . . . . . . . 68 12.2 Informative References . . . . . . . . . . . . . . . . . . 72
11.11 Early Termination of a Session . . . . . . . . . . . . . 69
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 70
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 71
13.1 Normative References . . . . . . . . . . . . . . . . . . . 71
13.2 Informative References . . . . . . . . . . . . . . . . . . 72
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 73 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 73
Intellectual Property and Copyright Statements . . . . . . . 75 A. Example Sequence of Separate NAP and ISP Authentication . . 75
Intellectual Property and Copyright Statements . . . . . . . 77
1. Introduction 1. Introduction
Network access authentication has traditionally been a layer 2 Providing secure network access service requires access control based
function. This document specifies a protocol that enables EAP to be on the authentication and authorization of the clients and the access
transported above the IP layer. As a result, network access networks. Client-to-network authentication provides parameters that
authentication can be made a function of the network layer thereby are needed to police the traffic flow through the enforcement points.
achieving link-layer independence for the process of authenticating a A protocol is needed to carry authentication methods between the
client seeking access to a network. At the present time, there are client and the access network.
no standardized solutions for authenticating a host for network
access at the network layer. The problem statement for which the
PANA protocol is a solution can be found in Appendix A of
[I-D.ietf-pana-requirements].
PANA relies on EAP for the actual authentication of a client. It Currently there is no standard network-layer solution for
does not define any new authentication protocols or schemes. It authenticating clients for network access. Appendix A of
enables EAP messages to be carried between the client and the [I-D.ietf-pana-requirements] describes the problem statement that led
network. The actual choice of a specific EAP method to be run over to the development of PANA.
PANA is dependent on the underlying access network technology. The
key factor in the choice of the EAP method is the determination of
whether the lower layer (link/physical) provides security for the
PANA messages.
A secure network access authentication framework goes beyond just Scope of this work is identified as designing a link-layer agnostic
authenticating the client to the network. Other aspects such as transport for network access authentication methods. The Extensible
address configuration, data traffic security, access control filters Authentication Protocol (EAP) [RFC3748] provides such authentication
and separation of the enforcement point from the protocol end-point methods. In other words, PANA will carry EAP which can carry various
are documented in [I-D.ietf-pana-framework] and [I-D.ietf-pana-snmp]. authentication methods. By the virtue of enabling transport of EAP
above IP, any authentication method that can be carried as an EAP
method is made available to PANA and hence to any link-layer
technology. There is a clear division of labor between PANA (an EAP
lower layer), EAP and EAP methods as described in [RFC3748].
This document specifies the client-network interaction and the Various environments and usage models for PANA are identified in
messages defined for this purpose. Appendix A of [I-D.ietf-pana-requirements]. Potential security
threats for network-layer access authentication protocol are
discussed in [I-D.ietf-pana-threats-eval]. These have been essential
in defining the requirements [I-D.ietf-pana-requirements] on the PANA
protocol. Note that some of these requirements are imposed by the
chosen payload, EAP [RFC3748].
There are components that are part of a complete secure network
solution but are outside of the PANA protocol specification,
including IP address configuration, authentication method choice,
filter rule installation, data traffic protection and PAA-EP
protocol. These components are described in separate documents (see
[I-D.ietf-pana-framework] and [I-D.ietf-pana-snmp]). The readers are
recommended to go through the PANA Framework document
[I-D.ietf-pana-framework] prior to reading this protocol
specification document.
1.1 Specification of Requirements 1.1 Specification of Requirements
In this document, several words are used to signify the requirements In this document, several words are used to signify the requirements
of the specification. These words are often capitalized. The key of the specification. These words are often capitalized. The key
words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD",
"SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document
are to be interpreted as described in [RFC2119]. are to be interpreted as described in [RFC2119].
2. Terminology 2. Terminology
PANA Client (PaC): PANA Client (PaC):
The client side of the protocol that resides in the host device. The client side of the protocol that resides in the access device
It is responsible for providing the credentials in order to prove (e.g., laptop, PDA, etc.). It is responsible for providing the
its identity for network access authorization. credentials in order to prove its identity (authentication) for
network access authorization. The PaC and the EAP peer are
co-located in the same access device.
PANA Authentication Agent (PAA): PANA Authentication Agent (PAA):
The protocol entity in the access network whose responsibility is The protocol entity in the access network whose responsibility is
to verify the credentials provided by a PANA client (PaC) and to verify the credentials provided by a PANA client (PaC) and
authorize network access to the device associated with the client authorize network access to the device associated with the client
and identified by a Device Identifier (DI). Note the and identified by a Device Identifier (DI). The PAA and the EAP
authentication and authorization procedure can, according to the authenticator (and optionally the EAP server) are co-located in
EAP model, be also offloaded to the backend AAA infrastructure. the same node. Note the authentication and authorization
procedure can, according to the EAP model, be also offloaded to
the backend AAA infrastructure.
PANA Session: PANA Session:
A PANA session begins with the handshake between the PANA Client A PANA session begins with the handshake between the PANA Client
(PaC) and the PANA Authentication Agent (PAA), and terminates as a (PaC) and the PANA Authentication Agent (PAA), and terminates as a
result of an authentication failure, a timeout, or an explicit result of an authentication or liveness test failure, a message
termination message. A fixed session identifier is maintained delivery failure after retransmissions reach maximum values,
throughout a session. A session cannot be shared across multiple session lifetime expiration, or an explicit termination message.
network interfaces. A fixed session identifier is maintained throughout a session. A
session cannot be shared across multiple network interfaces. Only
one device identifier of the PaC is allowed to be bound to a PANA
session for simplicity.
Session Identifier: Session Identifier:
This identifier is used to uniquely identify a PANA session on the This identifier is used to uniquely identify a PANA session on the
PAA and PaC. It includes an identifier of the PAA, therefore it PAA and PaC. It includes an identifier of the PAA, therefore it
cannot be shared across multiple PAAs. It is included in PANA cannot be shared across multiple PAAs. It is included in PANA
messages to bind the message to a specific PANA session. This messages to bind the message to a specific PANA session. This
bidirectional identifier is allocated by the PAA following the bidirectional identifier is allocated by the PAA following the
handshake and freed when the session terminates. handshake and freed when the session terminates.
PANA Security Association (PANA SA): PANA Security Association (PANA SA):
A PANA security association is a relationship between the PaC and A PANA security association is formed between the PaC and the PAA
PAA, formed by the sharing of cryptographic keying material and by sharing cryptographic keying material and associated context.
associated context. Security associations are duplex. That is, The formed duplex security association is used to protect the
one security association is needed to protect the bidirectional bidirectional PANA signaling traffic between the PaC and the PAA.
traffic between the PaC and the PAA.
Device Identifier (DI): Device Identifier (DI):
The identifier used by the network as a handle to control and The identifier used by the network as a handle to control and
police the network access of a client. Depending on the access police the network access of a device. Depending on the access
technology, this identifier may contain an address that is carried technology, this identifier may contain an address that is carried
in protocol headers (e.g., IP or link-layer address), or a locally in protocol headers (e.g., IP or link-layer address), or a locally
significant identifier that is made available by the local significant identifier that is made available by the local
protocol stack (e.g., circuit id, PPP interface id) of a connected protocol stack (e.g., circuit id, PPP interface id) of a connected
device. device.
Enforcement Point (EP): Enforcement Point (EP):
A node on the access network where per-packet enforcement policies A node on the access network where per-packet enforcement policies
(i.e., filters) are applied on the inbound and outbound traffic of (i.e., filters) are applied on the inbound and outbound traffic of
client devices. Information such as the DI and (optionally) access devices. Information such as the DI and (optionally)
cryptographic keys are provided by the PAA per client for cryptographic keys are provided by the PAA per client for
generating filters on the EP. generating filters on the EP. The EP and PAA may be co-located.
Network Access Provider (NAP): Network Access Provider (NAP):
A service provider that provides physical and link-layer A service provider that provides physical and link-layer
connectivity to an access network it manages. connectivity to an access network it manages.
AAA-Key: AAA-Key:
A key derived by the EAP peer and EAP server and transported to A key derived by the EAP peer and EAP server and transported to
the authenticator [I-D.ietf-eap-keying]. the authenticator [I-D.ietf-eap-keying].
For additional terminology definitions see the PANA framework
document [I-D.ietf-pana-framework].
3. Protocol Overview 3. Protocol Overview
The PANA protocol is run between a client (PaC) and a server (PAA) in The PANA protocol is run between a client (PaC) and a server (PAA) in
order to perform authentication and authorization for the network order to perform authentication and authorization for the network
access service. access service.
The protocol messaging consists of a series of request and responses, The protocol messaging consists of a series of request and responses,
some of which may be initiated by either ends. Each message can some of which may be initiated by either ends. Each message can
carry zero or more AVPs as payload. The main payload of PANA is EAP carry zero or more AVPs as payload. The main payload of PANA is EAP
which performs authentication. PANA helps PaC and PAA establish an which performs authentication. PANA helps the PaC and PAA establish
EAP session. an EAP session.
PANA is a UDP-based protocol. It has its own retransmission PANA is a UDP-based protocol. It has its own retransmission
mechanism to reliably deliver messages. mechanism to reliably deliver messages.
PANA messages are sent between a PaC and PAA as part of a PANA PANA messages are sent between the PaC and PAA as part of a PANA
session. A PANA session consists of distinct phases: session. A PANA session consists of distinct phases:
o Discovery and handshake phase: This is the phase that initiates a o Discovery and handshake phase: This is the phase that initiates a
new PANA session. The PaC discovers the PAA(s) by either new PANA session. The PaC discovers the PAA(s) by either
explicitly soliciting advertisements for them or receiving explicitly soliciting advertisements for them or receiving
unsolicited advertisements. The PaC's answer sent in response to unsolicited advertisements. The PaC's answer sent in response to
an advertisement starts a new session. an advertisement starts a new session.
o Authentication phase: Immediately following the handshake phase is o Authentication and authorization phase: Immediately following the
the EAP execution between the PAA and PaC. The EAP payloads discovery and handshake phase is the EAP execution between the PAA
(which carry an EAP method inside) is what is used for and PaC. The EAP payload (which carry an EAP method inside) is
authentication. Authentication phase may involve execution of two what is used for authentication. The PAA conveys the result of
EAP sessions back-to-back, one for the NAP and one for the ISP. authentication and authorization to the PaC at the end of this
phase. This phase may involve execution of two EAP sessions
back-to-back, one for the NAP and one for the ISP.
o Authorization phase: Following a successful PANA authentication o Access phase: After a successful authentication and authorization
phase, the PaC gains access to the network and can send and the host gains access to the network and can send and receive IP
receive IP data traffic through EP. During this phase, the PaC data traffic through the EP(s). At any time during this phase,
and PAA may optionally ping each other to test liveness of the the PaC and PAA may optionally ping each other to test liveness of
PANA session on each end. the PANA session on each end.
o Re-authentication phase: Following an authorization phase, the PAA o Re-authentication phase: Following the access phase, the PAA must
must initiate re-authentication before the PANA session lifetime initiate re-authentication before the PANA session lifetime
expires. Again EAP is carried by PANA to perform authentication. expires. Again EAP is carried by PANA to perform authentication.
This phase may be optionally triggered by both the PaC and the PAA This phase may be optionally triggered by both the PaC and the PAA
without any respect to the session lifetime. The session moves to without any respect to the session lifetime. The session moves to
this phase from authorized phase, and returns back there upon this phase from the access phase, and returns back there upon
successful re-authentication. successful re-authentication.
o Termination phase: The PaC or PAA may choose to discontinue the o Termination phase: The PaC or PAA may choose to discontinue the
access service at any time. An explicit disconnect message can be access service at any time. An explicit disconnect message can be
sent by either end. If either the PaC or the PAA disconnects sent by either end. If either the PaC or the PAA disconnects
without engaging in termination messaging, it is expected that without engaging in termination messaging, it is expected that
either the expiration of a finite session lifetime or failed either the expiration of a finite session lifetime or failed
liveness tests would do the job. liveness tests would do the job.
PaC PAA Message[AVPs] PaC PAA Message
----------------------------------------------------- -----------------------------------------------------
// Discovery and handshake phase // Discovery and handshake phase
-----> PANA-PAA-Discover -----> PANA-PAA-Discover
<----- PANA-Start-Request <----- PANA-Start-Request
-----> PANA-Start-Answer -----> PANA-Start-Answer
// Authentication phase // Authentication and authorization phase
<----- PANA-Auth-Request /* EAP Request */ <----- PANA-Auth-Request /* EAP Request */
-----> PANA-Auth-Answer -----> PANA-Auth-Answer
-----> PANA-Auth-Request /* EAP Response */ -----> PANA-Auth-Request /* EAP Response */
<----- PANA-Auth-Answer <----- PANA-Auth-Answer
<----- PANA-Bind-Request /* EAP Success */ <----- PANA-Bind-Request /* EAP Success */
-----> PANA-Bind-Answer -----> PANA-Bind-Answer
// Authorization phase (IP data traffic allowed) // Access phase (IP data traffic allowed)
<----- PANA-Ping-Request <----- PANA-Ping-Request
-----> PANA-Ping-Answer -----> PANA-Ping-Answer
// Termination phase // Termination phase
-----> PANA-Termination-Request -----> PANA-Termination-Request
<----- PANA-Termination-Answer <----- PANA-Termination-Answer
Figure 1: Illustration of PANA Messages in a Session Figure 1: Illustration of PANA messages in a session
Note that depending on the environment and deployment the protocol
flow depicted in Figure 1 can be abbreviated.
Cryptographic protection of messages between the PaC and PAA is Cryptographic protection of messages between the PaC and PAA is
possible as soon as EAP in conjunction with the EAP method exports a possible as soon as EAP in conjunction with the EAP method exports a
shared key. That shared key is used to create a PANA SA. The PANA shared key. That shared key is used to create a PANA SA. The PANA
SA helps generating per-message authentication codes that provide SA helps generating per-message authentication codes that provide
integrity protection and authentication. integrity protection and authentication.
PANA also allows creation of a new PANA session with a new PAA out of
an existing session with another PAA. This optimization allows PaC
achieve quicker authorization without having to run EAP upon movement
(changing PAAs).
Throughout the lifetime of a session, various problems found with the Throughout the lifetime of a session, various problems found with the
incoming messages can generate a PANA error message sent in response. incoming messages can generate a PANA error message sent in response.
4. Protocol Details 4. Protocol Details
The following sections explain in detail the various phases of a PANA The following sections explain in detail the various phases of a PANA
session. session.
4.1 Discovery and Handshake Phase 4.1 Payload Encoding
The payload of any PANA message consists of zero or more AVPs
(Attribute Value Pairs). The subsequent sections refer to these
AVPs, therefore the list of AVPs are provided with a brief
description before more extensive descriptions are included later in
the document.
o Cookie AVP: contains a random value that is generated by the PAA
and used for making PAA discovery robust against blind resource
consumption DoS attacks.
o Protection-Capability AVP: contains the type of per-packet
protection (link-layer vs. network-layer) when a cryptographic
mechanism should be enabled after PANA authentication.
o Device-Id AVP: contains a device identifier (link-layer address or
an IP address) of the PaC or an EP.
o EAP AVP: contains an EAP PDU.
o MAC AVP: contains a Message Authentication Code that integrity
protects the PANA message.
o Termination-Cause AVP: contains the reason of session termination.
o Result-Code AVP: contains information about the protocol execution
results.
o Session-Id AVP: contains the PANA session identifier value.
o Session-Lifetime AVP: contains the duration of authorized access.
o Failed-AVP: contains an offending AVP that caused a failure.
o Provider-Identifier AVP: contains the identifier of a NAP or an
ISP.
o Provider-Name AVP: contains a name of a NAP or an ISP.
o NAP-Information AVP, ISP-Information AVP: contains the identifier
of a NAP and an ISP, respectively.
o Key-Id AVP: contains a AAA-Key identifier.
o PPAC AVP: Post-PANA-Address-Configuration AVP. Used to indicate
the available/chosen IP address configuration methods that can be
used by the PaC after successful PANA authentication.
o Nonce AVP: contains a randomly chosen value that is used in
cryptographic key computations.
o IP-Address AVP: contains an IP Address of the PaC.
o Notification AVP: contains a displayable message.
4.2 Discovery and Handshake Phase
When a PaC attaches to a network, and knows that it has to discover a When a PaC attaches to a network, and knows that it has to discover a
PAA, it SHOULD send a PANA-PAA-Discover message to a well-known link PAA, it SHOULD send a PANA-PAA-Discover message to a well-known link
local multicast address (TBD) and UDP port (TBD). The PANA PAA local multicast address (TBD) and UDP port (TBD). The PAA discovery
discovery assumes that the PaC and the PAA are one hop away from each assumes that the PaC and the PAA are one IP hop away from each other.
other. If the PaC knows the IP address of the PAA (based on If the PaC knows the IP address of the PAA (based on
pre-configuration), it MAY unicast the PANA-PAA-Discover message to pre-configuration), it MAY unicast the PANA-PAA-Discover message to
that address. that address.
When the PAA receives a PANA-PAA-Discover message from a PaC, the PAA When the PAA receives a PANA-PAA-Discover message from a PaC, the PAA
SHOULD unicast a PANA-Start-Request message to the PaC. SHOULD unicast a PANA-Start-Request message to the PaC.
The PaC MAY also choose to start sending packets before getting The PaC MAY also choose to start sending data packets before getting
authenticated. In that case, the network may detect this and the PAA authenticated. The EP in an access network that implements PANA
MAY send an unsolicited PANA-Start-Request message to the PaC in SHOULD drop unauthorized packets upon receipt. Additionally, the EP
addition to filtering the unauthorized traffic. The EP is the node MAY also take this traffic as an indication of unauthorized PaC and
that can detect such activity. The PAA-to-EP protocol MAY be used notify the PAA. The EP-to-PAA notification SHOULD be sent via
for this purpose. [I-D.ietf-pana-snmp]. In response, the PAA SHOULD send an
unsolicited PANA-Start-Request message to the PaC. This is called
"traffic-driven PAA discovery" (an alternative to the PaC explicitly
soliciting for a PAA). Note that this optional feature MAY NOT be
present in all deployments, therefore the PaC MUST NOT assume its
availability. The EP-to-PAA notification MAY also be generated in
response to receiving a link-up event notification on the EP
[I-D.ietf-dna-link-information].
When a PaC receives a PANA-Start-Request message from a PAA, it When the PaC receives a PANA-Start-Request message from a PAA, it
responds with a PANA-Start-Answer message if it wishes to enter an responds with a PANA-Start-Answer message if it wishes to enter the
authentication phase. The answer message copies the sequence number. authentication and authorization phase.
There can be multiple PAAs on the link and a PaC may receive multiple There can be multiple PAAs on the link and the PaC may receive
PANA-Start-Request messages from those PAAs. The authentication and multiple PANA-Start-Request messages from those PAAs. The
authorization result does not depend on which PAA is chosen by the authentication and authorization result does not depend on which PAA
PaC. By default the PaC MAY choose the PAA that sent the first is chosen by the PaC. By default the PaC MAY choose the PAA that
response. sent the first response.
A PANA-Start-Request message MAY carry a Cookie AVP that contains a A PANA-Start-Request message MAY carry a Cookie AVP that contains a
cookie. The sequence number is set to a randomly picked initial random value generated by the PAA. The random value is referred to
sequence number. The cookie is used for preventing the PAA from as a cookie. The cookie is used for preventing the PAA from resource
resource consumption DoS attacks by blind attackers. The cookie is consumption DoS attacks by blind attackers which bombard the PAA with
computed in such a way that it does not require any per-session state PANA-PAA-Discover messages. By relying on a cookie mechanism the PAA
maintenance on the PAA in order to verify the cookie returned in a can avoid per-PaC state creation until after the PaC can produce the
PANA-Start-Answer message. The exact algorithms and syntax used for same cookie in its PANA-Start-Answer message. In order to do that,
generating cookies does not affect interoperability and hence is not the cookie MUST be computed in such a way that it does not require
specified here. An example algorithm is described below. any per-session state maintenance on the PAA in order to verify the
cookie returned in the PANA-Start-Answer message. The PAA discovery
that takes advantage of cookies is called "stateless PAA discovery".
The exact algorithms and syntax used by the PAA to generate cookies
does not affect interoperability and hence is not specified here. An
example algorithm is described below.
Cookie = Cookie =
<secret-version> | HMAC_SHA1( <Device-Id of PaC> , <secret> ) <secret-version> | HMAC_SHA1( <Device-Id of PaC> , <secret> )
where <secret> is a randomly generated secret known only to the PAA, where <secret> is a randomly generated secret known only to the PAA,
<secret-version> is an index used for choosing the secret for <secret-version> is an index used for choosing the secret for
generating the cookie and '|' indicates concatenation. The generating the cookie and '|' indicates concatenation. The
secret-version should be changed frequently enough to prevent replay secret-version should be changed frequently enough to prevent replay
attacks. The secret key is valid for a certain time frame. attacks. The secret key is valid for a certain time frame. The
device identifier of the PaC can be extracted from a link-layer or IP
header of PANA messages.
When the PaC sends a PANA-Start-Answer message in response to a When the PaC sends a PANA-Start-Answer message in response to a
PANA-Start-Request containing a Cookie AVP, the answer MUST contain a PANA-Start-Request containing a Cookie AVP, the answer MUST contain a
Cookie AVP with the cookie value copied from the request. Cookie AVP with the cookie value copied from the request.
When the PAA receives the PANA-Start-Answer message from the PaC, it When the PAA receives the PANA-Start-Answer message from the PaC, it
verifies the cookie. The cookie is considered as valid if the verifies the cookie. The cookie is considered as valid if the
received cookie has the expected value. If the computed cookie is received cookie has the expected value. If the computed cookie is
valid, the protocol enters an authentication phase. Otherwise, it valid, the protocol enters the authentication and authorization
MUST silently discard the received message. phase. Otherwise, it MUST silently discard the received message.
Initial EAP Request MAY be optionally carried by the The initial EAP Request message MAY be optionally carried by the
PANA-Start-Request (as opposed to by a later PANA-Auth-Request) PANA-Start-Request (as opposed to by a later PANA-Auth-Request)
message in order to reduce the number of round-trips. This message in order to reduce the number of round-trips. This
optimization SHOULD NOT be used if the PAA discovery is desired to be optimization SHOULD NOT be used if the PAA discovery is desired to be
stateless. stateless since transmission of an EAP Request message creates a
state at EAP layer. See [I-D.ietf-eap-statemachine] for more
information on the EAP state machine and the allocation of state
information in the respective protocol steps.
A Protection-Capability AVP and a Post-PANA-Address-Configuration A Protection-Capability AVP and a Post-PANA-Address-Configuration
(PPAC) AVP MAY be included in the PANA-Start-Request in order to (PPAC) AVP MAY be included in the PANA-Start-Request in order to
indicate required and available capabilities for the network access. indicate required and available capabilities for the network access.
These AVPs MAY be used by the PaC for assessing the capability match These AVPs MAY be used by the PaC for assessing the capability match
even before the authentication takes place. But these AVPs are even before the authentication takes place. Since these AVPs are
provided during the insecure discovery and handshake phase, there are provided during the insecure discovery and handshake phase, there are
certain security risks involved in using the provided information. certain security risks involved in using the provided information.
See Section 11 for further discussion on this. See Section 10 for further discussion on this.
If the initial EAP Request message is carried in the If the initial EAP Request message is carried in the
PANA-Start-Request message, an EAP Response message MUST be carried PANA-Start-Request message, an EAP Response message MUST be carried
in the PANA-Start-Answer message returned to the PAA. in the PANA-Start-Answer message returned to the PAA.
In any case, PANA MUST NOT generate an EAP message on behalf of EAP The PANA-Start-Request/Answer exchange is needed before entering the
peer or EAP (pass-through) authenticator. authentication and authorization phase even when the PaC is
pre-configured with the IP address of the PAA and the
The PANA-Start-Request/Answer exchange is needed before entering an PANA-PAA-Discover message is unicast.
authentication phase even when the PaC is pre-configured with PAAs IP
address and the PANA-PAA-Discover message is unicast.
A Nonce AVP MUST be included in PANA-Start-Request and A Nonce AVP MUST be included in the PANA-Start-Request and
PANA-Start-Answer messages. The nonces are used to establish a PANA PANA-Start-Answer messages. The nonces are used to establish a fresh
SA. PANA_MAC_KEY (see Section 5.3) which is a transient session key in
the EAP key hierarchy [I-D.ietf-eap-keying] and is used only in the
PANA protocol. A Nonce AVP MUST be included in the
PANA-Start-Request and PANA-Start-Answer messages. The nonces are
used to establish a PANA SA.
A PANA-Start-Request message that carries a Cookie AVP is never A PANA-Start-Request message in stateless PAA discovery MUST NOT be
retransmitted. A PANA-Start-Request message that does not carry a retransmitted as this voids the statelessness on the PAA. Instead,
Cookie AVP is retransmitted based on timer. A PANA-Start-Answer the PaC MUST retransmit the PANA-PAA-Discover message until it
message that carries a Cookie AVP is retransmitted based on timer. A receives a PANA-Start-Request message, and retransmit the
PANA-Start-Answer message that does not carry a Cookie AVP is never PANA-Start-Answer message until it receives a PANA-Auth-Request
retransmitted based on timer. message. The PaC can determine whether the PAA is using stateless
PAA discovery by the presence of Cookie AVP. The PANA-Start-Request
message MUST be retransmitted instead of the PANA-Start-Answer
message when stateless PAA discovery is not used.
It is possible that both the PAA and the PaC initiate the discovery It is possible that both the PAA and the PaC initiate the discovery
and handshake procedure at the same time, i.e., the PAA sends a and handshake procedure at the same time, i.e., the PAA sends a
PANA-Start-Request message while the PaC sends a PANA-PAA-Discover PANA-Start-Request message while the PaC sends a PANA-PAA-Discover
message. To resolve the race condition, the PAA SHOULD silently message. To resolve the race condition, the PAA SHOULD silently
discard the PANA-PAA-Discover message received from the PaC after it discard the PANA-PAA-Discover message received from the PaC after it
has sent a PANA-Start-Request message with creating a state (i.e., no has sent a PANA-Start-Request message with creating a state (i.e., no
Cookie AVP is included in the message) for the PaC. In this case PAA Cookie AVP is included in the message) for the PaC. In this case the
will retransmit PANA-Start-Request based on a timer, if PaC doesn't PAA will retransmit the PANA-Start-Request message based on a timer,
respond in time (message was lost for example). If the PAA had sent if the PaC doesn't respond in time (the message was lost for
a PANA-Start-Request message without creating a state for the PaC example). If the PAA had sent a PANA-Start-Request message without
(i.e., a Cookie AVP was included in the message), then it SHOULD creating a state for the PaC (i.e., a Cookie AVP was included in the
answer to the PANA-PAA-Discover message. message), then it SHOULD answer to the PANA-PAA-Discover message.
Figure 2 shows an example sequence for the discovery and handshake Figure 2 shows an example sequence for the discovery and handshake
phase when a PANA-PAA-Discover message is sent by the PaC. Figure 3 phase when a PANA-PAA-Discover message is sent by the PaC. Figure 3
shows an example sequence for the discovery and handshake phase that shows an example sequence for the discovery and handshake phase with
is triggered by data traffic. traffic-driven PAA discovery.
PaC PAA Message(seqno)[AVPs] PaC PAA Message(sequence number)[AVPs]
------------------------------------------------------ ------------------------------------------------------
-----> PANA-PAA-Discover(0) -----> PANA-PAA-Discover(0)
<----- PANA-Start-Request(x)[Nonce, Cookie] <----- PANA-Start-Request(x)[Nonce, Cookie]
-----> PANA-Start-Answer(x)[Nonce, Cookie] -----> PANA-Start-Answer(x)[Nonce, Cookie]
(continued to authentication phase) (continued to the authentication and
authorization phase)
Figure 2: Example Sequence for Discovery and Handshake Phase when Figure 2: Example sequence for the discovery and handshake phase when
PANA-PAA-Discover is sent by PaC PANA-PAA-Discover is sent by the PaC
PaC EP PAA Message(seqno)[AVPs] PaC EP PAA Message(sequence number)[AVPs]
------------------------------------------------------ ------------------------------------------------------
---->o (Data packet arrival or L2 trigger) ---->o (Data packet arrival or L2 trigger)
------> PAA-to-EP protocol, or another mechanism ------> PAA-to-EP protocol, or another mechanism
<------------ PANA-Start-Request(x)[Nonce, Cookie] <------------ PANA-Start-Request(x)[Nonce, Cookie]
------------> PANA-Start-Answer(x)[Nonce, Cookie] ------------> PANA-Start-Answer(x)[Nonce, Cookie]
(continued to authentication phase) (continued to the authentication and
authorization phase)
Figure 3: Example Sequence for Discovery and Handshake when discovery Figure 3: Example sequence for the discovery and handshake phase with
is triggered by data traffic traffic-driven PAA discovery
4.2 Authentication Phase 4.3 Authentication and Authorization Phase
The main task in authentication phase is to carry EAP messages The main task of the authentication and authorization phase is to
between the PaC and the PAA. EAP Request and Response messages are carry EAP messages between the PaC and the PAA. EAP Request and
carried in PANA-Auth-Request messages. PANA-Auth-Answer messages are Response messages are carried in PANA-Auth-Request messages.
simply used to acknowledge receipt of the requests. As an PANA-Auth-Answer messages are simply used to acknowledge receipt of
optimization, a PANA-Auth-Answer message MAY include the EAP the requests. As an optimization, a PANA-Auth-Answer message MAY
Response. Another optimization allows optionally carrying the first include the EAP Response message. This optimization MAY not be used
EAP Request/Response in PANA-Start-Request/Answer message as when it takes time to generate the EAP Response message (due to,
described in Section 4.1 e.g., intervention of human input), in which case returning an
EAP-Auth-Answer message without piggybacking an EAP Response message
can avoid unnecessary retransmission of the PANA-Auth-Request
message. Another optimization allows optionally carrying the first
EAP Request/Response message in PANA-Start-Request/Answer message as
described in Section 4.2.
When an EAP Success/Failure message is sent from a PAA, the message PANA allows execution of two separate authentication methods, one
is carried in a PANA-Bind-Request (PBR) message. The with NAP and one with ISP under the same PANA session. This optional
PANA-Bind-Request messages MUST be acknowledged with a feature may be offered by the PAA and accepted by the PaC. When
PANA-Bind-Answer (PBA) message. Figure 4 shows an example sequence performed separately, the result of the first EAP authentication is
in an authentication phase. signaled via PANA-FirstAuth-End-Request and PANA-FirstAuth-End-Answer
message exchange which delineates the first method execution from the
next. See Section 4.7 for a detailed discussion on separate NAP and
ISP authentication.
PaC PAA Message(seqno)[AVPs] The result of PANA authentication is carried in a PANA-Bind-Request
message sent from the PAA to the PaC. This message carries the final
EAP authentication result (whether it is the second EAP
authentication result of NAP and ISP separate authentication, or the
sole EAP authentication result) and the result of PANA
authentication. The PANA-Bind-Request message MUST be acknowledged
with a PANA-Bind-Answer (PBA) message. Figure 4 shows an example
sequence in the authentication and authorization phase (no separate
authentication).
PaC PAA Message(sequence number)[AVPs]
-------------------------------------------------------------------- --------------------------------------------------------------------
(continued from discovery and handshake phase) (continued from the discovery and handshake phase)
<----- PANA-Auth-Request(x+1) <----- PANA-Auth-Request(x+1)
[Session-Id, EAP{Request}] [Session-Id, EAP{Request}]
-----> PANA-Auth-Answer(x+1) // No piggybacking EAP-Response -----> PANA-Auth-Answer(x+1) // No piggybacking EAP Response
[Session-Id] [Session-Id]
-----> PANA-Auth-Request(y) -----> PANA-Auth-Request(y)
[Session-Id, EAP{Response}] [Session-Id, EAP{Response}]
<----- PANA-Auth-Answer(y) <----- PANA-Auth-Answer(y)
[Session-Id] [Session-Id]
<----- PANA-Auth-Request(x+2) <----- PANA-Auth-Request(x+2)
[Session-Id, EAP{Request}] [Session-Id, EAP{Request}]
-----> PANA-Auth-Answer(x+2) // Piggybacking EAP-Response -----> PANA-Auth-Answer(x+2) // Piggybacking EAP Response
[Session-Id, EAP{Response}] [Session-Id, EAP{Response}]
<----- PANA-Bind-Request(x+3) <----- PANA-Bind-Request(x+3)
[Session-Id, EAP{Success}, Device-Id, IP-Address, [Session-Id, Result-Code, EAP{Success}, Device-Id,
Lifetime, Protection-Cap., PPAC, MAC] Key-Id, IP-Address, Lifetime, Protection-Cap., PPAC, MAC]
-----> PANA-Bind-Answer(x+3) -----> PANA-Bind-Answer(x+3)
[Session-Id, Device-Id, PPAC, MAC] [Session-Id, Device-Id, Key-Id, PPAC, MAC]
Figure 4: Example Sequence in Authentication Phase Figure 4: Example sequence for the authentication and authorization
phase
When an EAP method that is capable of deriving keys is used during When an EAP method that is capable of deriving keys is used during
the authentication phase and the keys are successfully derived, the the authentication and authorization phase and the keys are
PANA-FirstAuth-End-Request and PANA-FirstAuth-End-Answer and/or successfully derived, the PANA message that carries the EAP Success
PANA-Bind-Request and PANA-Bind-Answer messages, and all subsequent message (i.e., a PANA-FirstAuth-End-Request or a PANA-Bind-Request
PANA messages MUST contain a MAC AVP. message) and any subsequent message MUST contain a MAC AVP.
The PANA-Bind-Request and the PANA-Bind-Answer message exchange is The PANA-Bind-Request and the PANA-Bind-Answer message exchange is
also used for binding device identifiers of the PaC and EP(s), and also used for binding device identifiers of the PaC and EP(s), and
the IP address of the PAA to the PANA SA. To achieve this, the the IP address of the PAA to the PANA SA. To achieve this, the
PANA-Bind-Request SHOULD contain the device identifier(s) of the PANA-Bind-Request message MUST contain the device identifier in a
EP(s) in Device-Id AVP(s) when they are either MAC or IP address(es), Device-Id AVP for each EP if a Protection-Capability AVP is included
and the IP address of the PAA in an IP-Address AVP. PANA-Bind-Answer in the message. Otherwise, the message SHOULD contain the device
SHOULD contain PaC's device identifier in a Device-Id AVP when it is identifier in a Device-Id AVP for each EP when a link-layer or IP
already presented with that of EP(s). The PaC MUST use the same type address is used as the device identifier of the PaC. The
of device identifier as contained in the PANA-Bind-Request message. PANA-Bind-Request message MUST also contain the IP address of the PAA
This exchange when protected by a MAC AVP prevents man-in-the-middle in an IP-Address AVP. The PANA-Bind-Answer message MUST contain the
attacks. The PANA-Bind-Request message MAY also contain a PaC's device identifier in a Device-Id AVP when it is already
Protection-Capability AVP to indicate if link-layer or network-layer presented with that of EP(s) in the request with using the same type
ciphering should be initiated after PANA. No link layer or network of device identifier as contained in the request. If the
layer specific information is included in the Protection-Capability PANA-Bind-Answer message sent from the PaC does not contain a
AVP. When the information is preconfigured on the PaC and the PAA Device-Id AVP with the same device identifier type contained in the
this AVP can be omitted. It is assumed that at least PAA is aware of request, the PAA sends a PANA-Error-Request message with a
PANA_MISSING_AVP result code, and wait for a PANA-Error-Answer
message to terminate the session. The PANA-Bind-Request message with
a PANA_SUCCESS result code MUST also contain a Protection-Capability
AVP if link-layer or network-layer ciphering is enabled after the
authentication and authorization phase. The PANA-Bind-Request
message MAY also contain a Protection-Capability AVP to indicate if
link-layer or network-layer ciphering should be enabled after the
authentication and authorization phase. No link-layer or
network-layer specific information is included in the
Protection-Capability AVP. It is assumed that the PAA is aware of
the security capabilities of the access network. The PANA protocol the security capabilities of the access network. The PANA protocol
does not specify how the PANA SA and the Protection-Capability AVP does not specify how the PANA SA and the Protection-Capability AVP
will be used to provide per-packet protection for data traffic. will be used to provide per-packet protection for data traffic.
Additionally, PANA-Bind-Request MUST include a Additionally, the PANA-Bind-Request message with a PANA_SUCCESS
Post-PANA-Address-Configuration AVP, which helps PAA to inform PaC result code MUST include a Post-PANA-Address-Configuration (PPAC)
about whether a new IP address MUST be configured and the available AVP, which helps the PAA to inform the PaC about whether a new IP
methods to do so. PaC MUST include a PPAC AVP in order to indicate address MUST be configured and the available methods to do so. In
its choice of method when there is a match between the methods this case, the PaC MUST include a PPAC AVP in the PANA-Bind-Answer
offered by the PAA and the methods available on the PaC. When there message in order to indicate its choice of method when there is a
is no match, a PPAC AVP MUST NOT be included and the Result-Code AVP match between the methods offered by the PAA and the methods
MUST be set to PANA_PPAC_CAPABILITY_UNSUPPORTED in the available on the PaC. When there is no match, the PaC MUST send a
PANA-Bind-Answer message. PANA-Error-Request message with a PANA_PPAC_CAPABILITY_UNSUPPORTED
result code and terminate the PANA session.
PANA-Bind-Request and PANA-Bind-Answer messages MUST be retransmitted PANA-Bind-Request and PANA-Bind-Answer messages MUST be retransmitted
based on the retransmission rule described in Section 5.3. based on the retransmission rule described in Section 5.2.
EAP authentication can fail at a pass-through authenticator without EAP authentication can fail at a pass-through authenticator without
sending an EAP-Failure message [I-D.ietf-eap-statemachine]. When sending an EAP Failure message [I-D.ietf-eap-statemachine]. When
this occurs, the PAA SHOULD send a PANA-Error-Request message to the this occurs, the PAA SHOULD send a PANA-Error-Request message to the
PaC with using PANA_UNABLE_TO_COMPLY result code. The PaC SHOULD not PaC with using PANA_UNABLE_TO_COMPLY result code. The PaC SHOULD not
change its state unless the error message is secured by PANA or lower change its state unless the error message is secured by PANA or
layer. In any case, a more appropriate way is to rely on a timeout lower-layer. In any case, a more appropriate way is to rely on a
on the PaC. timeout on the PaC.
There is a case where EAP authentication succeeds with producing an There is a case where EAP authentication succeeds with producing an
EAP-Success message but network access authorization fails due to, EAP Success message but network access authorization fails due to,
e.g., authorization rejected by a AAA proxy or authorization locally e.g., authorization rejected by a AAA or authorization locally
rejected by the PAA. When this occurs, the PAA MUST send rejected by the PAA. When this occurs, the PAA MUST send a
PANA-Bind-Request with a result code PANA_AUTHORIZATION_REJECTED. If PANA-Bind-Request with a result code PANA_AUTHORIZATION_REJECTED. If
a AAA-Key is established between PaC and PAA by the time when the a AAA-Key is established between the PaC and the PAA by the time when
EAP-Success is generated by the EAP server (this is the case when the the EAP Success message is generated by the EAP server (this is the
EAP method provides protected success indication), this PANA-Bind case when the EAP method provides protected success indication), the
message exchange MUST be protected with a MAC AVP and with carrying a PANA-Bind-Request and PANA-Bind-Answer messages MUST be protected
Key-Id AVP. The AAA-Key and the PANA session MUST be deleted after with a MAC AVP and carry a Key-Id AVP. The AAA-Key and the PANA
the PANA-Bind message exchange. session MUST be deleted immediately after the PANA-Bind message
exchange.
4.3 Authorization Phase 4.4 Access Phase
Once an authentication phase or a re-authentication phase Once the authentication and authorization phase or the
successfully completes, the PaC gains access to the network and can re-authentication phase successfully completes, the PaC gains access
send and receive IP data traffic through EP and the PANA session to the network and can send and receive IP data traffic through the
enters an authorization phase. In this phase, PANA-Ping-Request and EP(s) and the PANA session enters the access phase. In this phase,
PANA-Ping-Answer messages are used for testing the liveness of the PANA-Ping-Request and PANA-Ping-Answer messages can be used for
PANA session on the PANA peer. Both the PaC and the PAA are allowed testing the liveness of the PANA session on the PANA peer. Both the
to send a PANA-Ping-Request message to the communicating peer PaC and the PAA are allowed to send a PANA-Ping-Request message to
whenever they need to make sure the availability of the session on the communicating peer whenever they need to make sure the
the peer and expect the peer to return a PANA-Ping-Answer message. availability of the session on the peer and expect the peer to return
Both PANA-Ping-Request and PANA-Ping-Answer messages MUST be a PANA-Ping-Answer message. Both PANA-Ping-Request and
protected with a MAC AVP when a PANA SA is available. PANA-Ping-Answer messages MUST be protected with a MAC AVP when a
PANA SA is available.
Implementations MUST limit the rate of performing this test. The PaC Implementations MUST limit the rate of performing this test. The PaC
and the PAA can handle rate limitation on their own, they do not have and the PAA can handle rate limitation on their own, they do not have
to perform any coordination with each other. There is no negotiation to perform any coordination with each other. There is no negotiation
of timers for this purpose. of timers for this purpose.
Figure 5 and Figure 6 show liveness tests as they are initiated by Figure 5 and Figure 6 show liveness tests as they are initiated by
the PaC and the PAA respectively. the PaC and the PAA respectively.
PaC PAA Message(seqno)[AVPs] PaC PAA Message(sequence number)[AVPs]
------------------------------------------------------ ------------------------------------------------------
-----> PANA-Ping-Request(q)[Session-Id, MAC] -----> PANA-Ping-Request(q)[Session-Id, MAC]
<----- PANA-Ping-Answer(q)[Session-Id, MAC] <----- PANA-Ping-Answer(q)[Session-Id, MAC]
Figure 5: Example Sequence for PaC-initiated liveness test Figure 5: Example sequence for PaC-initiated liveness test
PaC PAA Message(seqno)[AVPs] PaC PAA Message(sequence number)[AVPs]
------------------------------------------------------ ------------------------------------------------------
<----- PANA-Ping-Request(p)[Session-Id, MAC] <----- PANA-Ping-Request(p)[Session-Id, MAC]
-----> PANA-Ping-Answer(p)[Session-Id, MAC] -----> PANA-Ping-Answer(p)[Session-Id, MAC]
Figure 6: Example Sequence for PAA-initiated liveness test Figure 6: Example sequence for PAA-initiated liveness test
4.4 Re-authentication Phase 4.5 Re-authentication Phase
A PANA session in an authorization phase can enter a The PANA session in the access phase can enter the re-authentication
re-authentication phase to extend the current session lifetime by phase to extend the current session lifetime by re-executing EAP.
re-executing EAP. Once the re-authentication phase successfully Once the re-authentication phase successfully completes, the session
completes, the session re-enters the authorization phase. Otherwise, re-enters the access phase. Otherwise, the session is deleted.
the session is deleted.
When a PaC wants to initiate re-authentication, it sends a When the PaC wants to initiate re-authentication, it sends a
PANA-Reauth-Request message to the PAA. This message MUST contain a PANA-Reauth-Request message to the PAA. This message MUST contain a
Session-Id AVP which is used for identifying the PANA session on the Session-Id AVP which is used for identifying the PANA session on the
PAA. If the PAA already has an established PANA session for the PaC PAA. If the PAA already has an established PANA session for the PaC
with the matching identifier, it MUST first respond with a with the matching session identifier, it MUST first respond with a
PANA-Reauth-Answer, followed by a PANA-Auth-Request that starts a new PANA-Reauth-Answer message, followed by a PANA-Auth-Request that
EAP authentication. If PAA cannot identify the session, it MUST starts a new EAP authentication. If the PAA cannot identify the
respond with a PANA-Error-Request with the error code session, it MAY respond with a PANA-Error-Request message with a
PANA_UNKNOWN_SESSION_ID. PANA-Reauth-Request/Answer messages MUST result code PANA_UNKNOWN_SESSION_ID. Transmission of this error
contain a MAC AVP when PANA SA is available. request is made optional in case this behavior is leveraged for a DoS
attack on the PAA.
PaC may receive a PANA-Auth-Request before receiving the answer to The PaC may receive a PANA-Auth-Request before receiving the answer
its outstanding PANA-Reauth-Request. This condition can arise due to to its outstanding PANA-Reauth-Request. This condition can arise due
packet re-ordering or a race condition between the PaC and PAA when to packet re-ordering or a race condition between the PaC and PAA
they both attempt to engage in re-authentication. PaC MUST keep when they both attempt to engage in re-authentication. The PaC MUST
discarding the received PANA-Auth-Requests until it receives the keep discarding the received PANA-Auth-Requests until it receives the
answer to its request. answer to its request.
When the PAA initiates re-authentication, it sends a When the PAA initiates re-authentication, it sends a
PANA-Auth-Request message containing the session identifier for the PANA-Auth-Request message containing the session identifier for the
PaC to enter an authentication phase. PAA SHOULD initiate EAP PaC to enter the re-authentication phase. The PAA SHOULD initiate
authentication before the current session lifetime expires. EAP re-authentication before the current session lifetime expires.
Re-authentication of an on-going PANA session MUST maintain the Re-authentication of an on-going PANA session MUST maintain the
existing sequence numbers. existing sequence numbers.
For any re-authentication, if there is an established PANA SA, For any re-authentication, if there is an established PANA SA,
PANA-Auth-Request and PANA-Auth-Answer messages MUST be protected by PANA-Auth-Request and PANA-Auth-Answer messages MUST be protected by
adding a MAC AVP to each message. Any subsequent EAP-based adding a MAC AVP to each message. Any subsequent EAP authentication
authentication MUST be performed with the same ISP and NAP that was MUST be performed with the same ISP and NAP that was selected during
selected during the initial authentication. An example sequence for the discovery and handshake phase. An example sequence for
a re-authentication initiated by a PaC is shown in Figure 7. re-authentication phase initiated by the PaC is shown in Figure 7.
PaC PAA Message(seqno)[AVPs] PaC PAA Message(sequence number)[AVPs]
------------------------------------------------------ ------------------------------------------------------
-----> PANA-Reauth-Request(q) -----> PANA-Reauth-Request(q)
[Session-Id, MAC] [Session-Id, MAC]
<----- PANA-Reauth-Answer(q) <----- PANA-Reauth-Answer(q)
[Session-Id, MAC] [Session-Id, MAC]
<----- PANA-Auth-Request(p) <----- PANA-Auth-Request(p)
[Session-Id, EAP{Request}, MAC] [Session-Id, EAP{Request}, MAC]
-----> PANA-Auth-Answer(p) // No piggybacking EAP-Response -----> PANA-Auth-Answer(p) // No piggybacking EAP Response
[Session-Id, MAC] [Session-Id, MAC]
-----> PANA-Auth-Request(q+1) -----> PANA-Auth-Request(q+1)
[Session-Id, EAP{Response}, MAC] [Session-Id, EAP{Response}, MAC]
<----- PANA-Auth-Answer(q+1) // No piggybacking EAP-Response <----- PANA-Auth-Answer(q+1) // No piggybacking EAP Response
[Session-Id, MAC] [Session-Id, MAC]
<----- PANA-Auth-Request(p+1) <----- PANA-Auth-Request(p+1)
[Session-Id, EAP{Request}, MAC] [Session-Id, EAP{Request}, MAC]
-----> PANA-Auth-Answer(p+1) // Piggybacking EAP-Response -----> PANA-Auth-Answer(p+1) // Piggybacking EAP Response
[Session-Id, EAP{Response}, MAC] [Session-Id, EAP{Response}, MAC]
<----- PANA-Bind-Request(p+2) <----- PANA-Bind-Request(p+2)
[Session-Id, EAP{Success}, Device-Id, [Session-Id, Result-Code, EAP{Success}, Device-Id, Key-Id,
IP-Address, Key-Id, Lifetime, IP-Address, Lifetime, Protection-Cap., PPAC, MAC]
Protection-Cap., PPAC, MAC]
-----> PANA-Bind-Answer(p+2) -----> PANA-Bind-Answer(p+2)
[Session-Id, Device-Id, Key-Id, PPAC, MAC] [Session-Id, Device-Id, Key-Id, PPAC, MAC]
Figure 7: Example Sequence for re-authentication initiated by PaC Figure 7: Example sequence for the re-authentication phase initiated
by PaC
4.5 Termination Phase 4.6 Termination Phase
A procedure for explicitly terminating a PANA session can be A procedure for explicitly terminating a PANA session can be
initiated either from the PaC (i.e., disconnect indication) or from initiated either from the PaC (i.e., disconnect indication) or from
the PAA (i.e., session revocation). The PANA-Termination-Request and the PAA (i.e., session revocation). The PANA-Termination-Request and
the PANA-Termination-Answer message exchanges are used for disconnect PANA-Termination-Answer message exchanges are used for disconnect
indication and session revocation procedures. indication and session revocation procedures.
The reason for termination is indicated in the Termination-Cause AVP. The reason for termination is indicated in the Termination-Cause AVP.
When there is an established PANA SA established between the PaC and When there is an established PANA SA between the PaC and the PAA, all
the PAA, all messages exchanged during the termination phase MUST be messages exchanged during the termination phase MUST be protected
protected with a MAC AVP. When the sender of the with a MAC AVP. When the sender of the PANA-Termination-Request
PANA-Termination-Request receives a valid acknowledgment, all states message receives a valid acknowledgment, all states maintained for
maintained for the PANA session MUST be deleted immediately. the PANA session MUST be deleted immediately.
PaC PAA Message(seqno)[AVPs] PaC PAA Message(sequence number)[AVPs]
------------------------------------------------------ ------------------------------------------------------
-----> PANA-Termination-Request(q)[Session-Id, MAC] -----> PANA-Termination-Request(q)[Session-Id, MAC]
<----- PANA-Termination-Answer(q)[Session-Id, MAC] <----- PANA-Termination-Answer(q)[Session-Id, MAC]
Figure 8: Example Sequence for Session Termination Figure 8: Example sequence for the termination phase triggered by PaC
5. Protocol Design Details and Processing Rules 4.7 Separate NAP and ISP Authentication
5.1 Payload Encoding PANA allows running at most two EAP sessions in sequence in the
authentication and authorization phase to support separate NAP and
ISP authentication as described in this section. A typical network
access authentication includes execution of one EAP method with the
ISP. This separation allows the PaC to perform an additional
authentication method for receiving differentiated services from the
NAP.
The payload of any PANA message consists of zero or more AVPs Currently, running multiple EAP sessions in sequence in the
(Attribute Value Pairs). A brief description of the AVPs defined in authentication and authorization phase is designed only for separate
this document is listed below: NAP and ISP authentication. It is not for running arbitrary number
of EAP sessions in sequence, or giving the PaC another chance to try
another EAP authentication method within an integrated NAP and ISP
authentication when an EAP authentication method fails.
o Cookie AVP: contains a random value that is used for making Within separate NAP and ISP authentication, the NAP authentication
handshake robust against blind resource consumption DoS attacks. and the ISP authentication are considered completely independent.
Presence or success of one should not effect the other. Making a
network access authorization decision based on the success or failure
of each authentication is a network policy issue.
o Protection-Capability AVP: contains information which protection 4.7.1 Negotiating Separate NAP and ISP Authentication
should be initiated after the PANA exchange (e.g., link-layer or
network layer protection).
o Device-Id AVP: contains a device identifier of the PaC or an EP. When the PaC and PAA negotiates in the discovery and handshake phase
A device identifier is represented as a pair of device identifier to perform separate NAP and ISP authentication, the PaC and the PAA
type and device identifier value. Either a layer-2 address or an operate in the following way in addition to the behavior defined in
IP address is used for the device identifier value when this AVP Section 4.2
is present.
o EAP AVP: contains an EAP PDU. In the discovery and handshake phase, the PAA MAY advertise
availability of separate NAP and ISP authentication
([I-D.ietf-pana-framework]) by setting the S-flag on the PANA header
of the PANA-Start-Request message.
o MAC AVP: contains a Message Authentication Code that protects a If the S-flag of the received PANA-Start-Request message is set, the
PANA message PDU. PaC can indicate its desire to perform separate NAP and ISP
authentication by setting the S-flag in the PANA-Start-Answer
message. If the S-flag of the received PANA-Start-Request message is
not set, the PaC MUST NOT set the S-flag in the PANA-Start-Answer
message sent back to the PAA.
o Termination-Cause AVP: contains the reason of session termination. If the S-flag in the PANA-Start-Answer message is not set, only one
authentication is performed (ISP-only) and the processing occurs as
described in Section 4.2.
o Result-Code AVP: contains information about the protocol execution When the S-flag is set in a PANA-Start-Request message, the initial
results. EAP Request message MUST NOT be carried in the PANA-Start-Request
message. (If the initial EAP Request message were contained in the
PANA-Start-Request message during the S-flag negotiation, the PaC
cannot tell whether the EAP Request message is for NAP authentication
or ISP authentication.)
o Session-Id AVP: contains the session identifier value. 4.7.2 Execution of Separate NAP and ISP Authentication
o Session-Lifetime AVP: contains the duration of authorized access. When the PaC and PAA have negotiated in the discovery and handshake
phase to perform separate NAP and ISP authentication, the PaC and the
PAA operate in the following way in addition to the behavior defined
in Section 4.3
o Failed-AVP: contains the offending AVP that caused a failure. o The S-flag of PANA-Auth-Request and PANA-Auth-Answer messages MUST
be set.
o NAP-Information AVP, ISP-Information AVP: contains the information o An EAP Success/Failure message is carried in a
on a NAP and an ISP, respectively. PANA-FirstAuth-End-Request (PFER) message as well as a
PANA-Bind-Request (PBR) message. The PANA-FirstAuth-End-Request
message MUST be used at the end of the first EAP authentication
and the PANA-Bind-Request MUST be used for the second EAP
authentication. The PANA-FirstAuth-End-Request messages MUST be
acknowledged with a PANA-FirstAuth-End-Answer (PFEA) message.
o Key-Id AVP: contains a AAA-Key identifier. o If the first EAP authentication has failed, the PAA can choose not
to perform the second EAP authentication by clearing the S-flag of
the PANA-FirstAuth-End-Request message. In this case, the S-flag
of the PANA-FirstAuth-End-Answer message sent by the PaC MUST be
cleared. If the S-flag of the PANA-FirstAuth-End-Request message
is set when the first EAP authentication has failed, the PaC can
choose not to perform the second EAP authentication by clearing
the S-flag of the PANA-FirstAuth-End-Answer message. If the first
EAP authentication failed and the S-flag is not set in the
PANA-FirstAuth-End-Answer message as a result of those operations,
the PANA session MUST be immediately deleted. Otherwise, the
second EAP authentication MUST be performed.
o PPAC AVP: Post-PANA-Address-Configuration AVP. Conveys the list o The PAA determines the execution order of NAP authentication and
of IP address configuration methods available when sent by the ISP authentication. In this case, the PAA can indicate which
PAA, and the chosen method when sent by the PaC. authentication (NAP authentication or ISP authentication) is
currently occurring by using N-flag in the PANA message header.
When NAP authentication is being performed, the N-flag MUST be
set. When ISP authentication is being performed, the N-flag MUST
NOT be set. The N-flag MUST NOT be set when S-flag is not set.
o Nonce AVP: contains a randomly chosen value. When the PaC and PAA have negotiated in the discovery and handshake
phase to perform separate NAP and ISP authentication, and the
lower-layer is insecure, the two EAP authentication methods used in
the separate authentication MUST be capable of deriving keys
(AAA-Key).
o IP-Address AVP: contains an IP Address of a PaC. 4.7.3 AAA-Key Calculation
5.2 Transport Layer When the PaC and PAA have negotiated in the discovery and handshake
phase to perform separate NAP and ISP authentication, if the
lower-layer is insecure, the two EAP authentication methods used in
the separate authentication MUST be capable of deriving keys. In
this case, if the first EAP authentication is successful, the
PANA-FirstAuth-End-Request and PANA-FirstAuth-End-Answer messages as
well as PANA-Auth-Request and PANA-Auth-Answer messages in the second
EAP authentication MUST be protected with the key derived from the
AAA-Key for the first EAP authentication. The PANA-Bind-Request and
PANA-Bind-Answer messages and all subsequent PANA messages exchanged
in the access phase, re-authentication phase and termination phase
MUST be protected either with the AAA-Key for the first EAP
authentication if the first EAP authentication succeeds and the
second EAP authentication fails, or with the AAA-Key for the second
EAP authentication if the first EAP authentication fails and the
second EAP authentication succeeds, or with the compound AAA-Key
derived from the two AAA-Keys, one for the first EAP authentication
and the other from the second EAP authentication, if both the first
and second EAP authentication succeed. See Section 5.3 for how to
derive the AAA-Key.
5. Protocol Design Details and Processing Rules
5.1 Transport Layer
PANA uses UDP as its transport layer protocol. The UDP port number PANA uses UDP as its transport layer protocol. The UDP port number
is TBD. All messages except for PANA-PAA-Discover are always is TBD. All messages except for PANA-PAA-Discover are always
unicast. PANA-PAA-Discover MAY be unicast when the PaC knows the IP unicast. The PANA-PAA-Discover message MAY be unicast when the PaC
address of the PAA. knows the IP address of the PAA.
5.2.1 Fragmentation 5.1.1 Fragmentation
PANA does not provide fragmentation of PANA messages. Instead, it PANA does not provide fragmentation of PANA messages. Instead, it
relies on fragmentation provided by EAP methods and IP layer when relies on fragmentation provided by EAP methods and IP layer when
needed. needed.
5.3 Sequence Number and Retransmission 5.2 Sequence Number and Retransmission
PANA uses sequence numbers to provide ordered and reliable delivery PANA uses sequence numbers to provide ordered and reliable delivery
of messages. of messages.
PaC and PAA maintain two sequence numbers: the next one to be used The PaC and PAA maintain two sequence numbers: the next one to be
for a request it initiates and the next one it expects to see in a used for a request it initiates and the next one it expects to see in
request from the other end. These sequence numbers are 32-bit a request from the other end. These sequence numbers are 32-bit
unsigned numbers. They are monotonically incremented by 1 as new unsigned numbers. They are monotonically incremented by 1 as new
requests are generated and received, and wrapped to zero on the next requests are generated and received, and wrapped to zero on the next
message after 2^32-1. Answers always contain the same sequence message after 2^32-1. Answers always contain the same sequence
number as the corresponding request. Retransmissions maintain the number as the corresponding request. Retransmissions reuse the
same sequence number. sequence number contained in the original packet.
The initial sequence numbers (ISN) are randomly picked by PaC and PAA The initial sequence numbers (ISN) are randomly picked by the PaC and
as they send their very first request messages. PANA-PAA-Discover PAA as they send their very first request messages.
message carries sequence number 0. PANA-PAA-Discover message carries sequence number 0.
When a request message is received, it is considered valid in terms When a request message is received, it is considered valid in terms
of sequence numbers if and only if its sequence number matches the of sequence numbers if and only if its sequence number matches the
expected value. This check does not apply to PANA-PAA-Discover, and expected value. This check does not apply to the PANA-PAA-Discover,
the very first request messages. PANA-Start-Request messages.
When an answer message is received, it is considered valid in terms When an answer message is received, it is considered valid in terms
of sequence numbers if and only if its sequence number matches that of sequence numbers if and only if its sequence number matches that
of the currently outstanding request. A peer can only have one of the currently outstanding request. A peer can only have one
outstanding request at a time. outstanding request at a time.
PANA messages are retransmitted based on timer at until a response is PANA messages are retransmitted based on a timer until a response is
received (in which case the retransmission timer is stopped) or the received (in which case the retransmission timer is stopped) or the
number of retransmission reaches the maximum value (in which case the number of retransmission reaches the maximum value (in which case the
PANA session MUST be deleted immediately). The retransmission timer PANA session MUST be deleted immediately).
SHOULD be calculated as described in [RFC2988] to provide congestion
control. See Section 9 for default timer and maximum retransmission
count parameters.
PaC and PAA MUST respond to duplicate requests. Last transmitted The initial discovery and handshake phase requires special handling.
PANA answer MAY be cached in case it is not received by the peer and The PaC MUST retransmit the PANA-PAA-Discover message if a subsequent
that generates a retransmission of the last request. When available, PANA-Start-Request message is not received in time. Even though a
a cached answer can be used instead of fully processing the PANA-Start-Request message is received, the PANA-PAA-Discover message
retransmitted request and forming a new answer from scratch. may still have to be retransmitted. This is because stateless PAA
discovery requires one time transmission of a solicited
PANA-Start-Request message. The PAA MUST NOT start a timer and
retransmit the request in order to avoid state creation. If the
received PANA-Start-Request message included a Cookie AVP (an
indication of stateless PAA discovery), the PaC MUST retransmit the
PANA-PAA-Discover message until the first PANA-Auth-Request message
is received. Otherwise, the PaC can rely on the PAA to retransmit
the PANA-Start-Request message as soon as the PaC receives the first
one (i.e., the PaC can stop sending the PANA-PAA-Discover message).
The retransmission timers SHOULD be calculated as described in
[RFC2988] to provide congestion control. See Section 8 for default
timer and maximum retransmission count parameters.
The PaC and PAA MUST respond to duplicate requests. The last
transmitted answer MAY be cached in case it is not received by the
peer and that generates a retransmission of the last request. When
available, the cached answer can be used instead of fully processing
the retransmitted request and forming a new answer from scratch.
PANA MUST NOT generate EAP message duplication. EAP payload of a PANA MUST NOT generate EAP message duplication. EAP payload of a
retransmitted PANA message MUST NOT be passed to the EAP layer. retransmitted PANA message MUST NOT be passed to the EAP layer.
5.3 PANA Security Association
A PANA SA is created as an attribute of a PANA session when EAP
authentication succeeds with a creation of a AAA-Key. A PANA SA is
not created when the PANA authentication fails or no AAA-Key is
produced by any EAP authentication method. In the case where two EAP
sessions are performed in sequence in the PANA authentication and
authorization phase, it is possible that two AAA-Keys are derived.
If this happens, the PANA SA MUST be generated from both AAA-Keys.
When a new AAA-Key is derived in the PANA re-authentication phase,
any key derived from the old AAA-Key MUST be updated to a new one
that is derived from the new AAA-Key. In order to distinguish the
new AAA-Key from old ones, one Key-Id AVP MUST be carried in
PANA-Bind-Request and PANA-Bind-Answer messages or
PANA-FirstAuth-End-Request and PANA-FirstAuth-End-Answer messages at
the end of the EAP authentication which resulted in deriving a new
AAA-Key. The Key-Id AVP is of type Unsigned32 and MUST contain a
value that uniquely identifies the AAA-Key within the PANA session.
The PANA-Bind-Answer message (or the PANA-FirstAuth-End-Answer
message) sent in response to a PANA-Bind-Request message (or a
PANA-FirstAuth-End-Request message) with a Key-Id AVP MUST contain a
Key-Id AVP with the same AAA-Key identifier carried in the request.
PANA-Bind-Request, PANA-Bind-Answer, PANA-FirstAuth-End-Request and
PANA-FirstAuth-End-Answer messages with a Key-Id AVP MUST also carry
a MAC AVP whose value is computed by using the new PANA_MAC_KEY
derived from the new AAA-Key (or the new pair of AAA-Keys when the
PANA_MAC_KEY is derived from two AAA-Keys). Although the
specification does not mandate a particular method for calculation of
the Key-Id AVP value, a simple method is to use monotonically
increasing numbers.
The PANA session lifetime is bounded by the lifetime granted by the
authentication server (same as the AAA-Key lifetime). The lifetime
of the PANA SA (hence the PANA_MAC_KEY) is the same as the lifetime
of the PANA session. The created PANA SA is deleted when the
corresponding PANA session is deleted.
PANA SA attributes as well as PANA session attributes are listed
below:
PANA Session attributes:
* Session-Id
* Device-Id of PaC
* IP address of PaC (may be the same as the Device-Id of PaC when
IP address is used as the device identifier)
* IP address of PAA
* List of device identifiers of EPs
* Sequence number of the last transmitted request
* Sequence number of the last received request
* Last transmitted message payload
* Retransmission interval
* Session lifetime
* Protection-Capability
* PANA SA attributes:
+ Nonce generated by PaC (PaC_nonce)
+ Nonce generated by PAA (PAA_nonce)
+ AAA-Key
+ AAA-Key Identifier
+ PANA_MAC_KEY
The PANA_MAC_KEY is derived from the available AAA-Key(s) and it is
used to integrity protect PANA messages. If there is only one
AAA-Key available, e.g., due to ISP-only authentication, or with one
failed and one successful separate NAP and ISP authentication (see
Section 4.7), the PANA_MAC_KEY computation is based on that single
key. Otherwise, two AAA-Keys available to PANA can be combined in
following way ('|' indicates concatenation):
AAA-Key = AAA-Key1 | AAA-Key2
The PANA_MAC_KEY is computed in the following way:
PANA_MAC_KEY = The first N bits of
HMAC_SHA1(AAA-Key, PaC_nonce | PAA_nonce | Session-ID)
where the value of N depends on the integrity protection algorithm in
use, i.e., N=160 for HMAC-SHA1. The length of the AAA-Key MUST be N
bits or longer. See Section Section 5.4 for the detailed usage of
the PANA_MAC_KEY.
5.4 Message Authentication Code 5.4 Message Authentication Code
A PANA message can contain a MAC (Message Authentication Code) AVP A PANA message can contain a MAC (Message Authentication Code) AVP
for cryptographically protecting the message. for cryptographically protecting the message.
When a MAC AVP is included in a PANA message, the value field of the When a MAC AVP is included in a PANA message, the value field of the
MAC AVP is calculated by using the PANA_MAC_KEY in the following way: MAC AVP is calculated by using the PANA_MAC_KEY in the following way:
MAC AVP value = PANA_MAC_PRF(PANA_MAC_KEY, PANA_PDU) MAC AVP value = PANA_MAC_PRF(PANA_MAC_KEY, PANA_PDU)
skipping to change at page 21, line 50 skipping to change at page 28, line 20
When a PANA message is received, the message is considered to be When a PANA message is received, the message is considered to be
invalid at least when one of the following conditions are not met: invalid at least when one of the following conditions are not met:
o The IP Hop Limit (or TTL) field has a value of 255, i.e., the o The IP Hop Limit (or TTL) field has a value of 255, i.e., the
packet could not possibly have been forwarded by a router. packet could not possibly have been forwarded by a router.
o Each field in the message header contains a valid value including o Each field in the message header contains a valid value including
sequence number, message length, message type, version number, sequence number, message length, message type, version number,
flags, etc. flags, etc.
o When a device identifier of the PaC is bound to the PANA session,
it matches the device identifier carried in MAC or or IP header,
or other locally-significant identifier provided by the
lower-layers (e.g., circuit ID) unless the message is a
PANA-Update-Request with an IP-Address AVP.
o The message type is one of the expected types in the current o The message type is one of the expected types in the current
state. Specifically the following messages are unexpected and state. Specifically the following messages are unexpected and
invalid: invalid:
* In discovery and handshake phase: * In the discovery and handshake phase:
+ PANA-Termination-Request and PANA-Ping-Request. + PANA-Termination-Request and PANA-Ping-Request.
+ PANA-Bind-Request. + PANA-Bind-Request.
+ PANA-Update-Request. + PANA-Update-Request.
* In authentication phase: + PANA-Reauth-Request.
+ PANA-Error-Request.
* In the authentication and authorization phase and the
re-authentication phase:
+ PANA-PAA-Discover. + PANA-PAA-Discover.
+ PANA-Update-Request. + PANA-Update-Request.
+ PANA-Start-Request after a PaC receives the first valid + PANA-Start-Request after a PaC receives the first valid
PANA-Auth-Request. PANA-Auth-Request.
+ PANA-Termination-Request before the PaC receives the first + PANA-Termination-Request before the PaC receives the first
successful PANA-Bind-Request. successful PANA-Bind-Request.
* After successful PANA authentication: * In the access phase:
+ PANA-Start-Request as well as a non-duplicate + PANA-Start-Request as well as a non-duplicate
PANA-Bind-Request. PANA-Bind-Request.
+ PANA-PAA-Discover. + PANA-PAA-Discover.
* In termination phase: * In the termination phase:
+ PANA-PAA-Discover. + PANA-PAA-Discover.
+ All requests but PANA-Termination-Request. + All requests but PANA-Termination-Request.
o The message payload contains a valid set of AVPs allowed for the o The message payload contains a valid set of AVPs allowed for the
message type and there is no missing AVP that needs to be included message type and there is no missing AVP that needs to be included
in the payload. in the payload.
o Each AVP is decoded correctly. o Each AVP is decoded correctly.
o When a MAC AVP is included, the AVP value matches the MAC value o When a MAC AVP is included, the AVP value matches the MAC value
computed against the received message. computed against the received message.
o When a Device-Id AVP is included, the AVP is valid if the device o When a Device-Id AVP is included, the AVP is valid if the device
identifier type contained in the AVP is supported (check performed identifier type contained in the AVP is supported (check performed
by both PaC and PAA) and is the requested one (check performed by by both the PaC and the PAA) and is the requested one (check
PAA only) and the device identifier value contained in the AVP performed by the PAA only) and the device identifier value
matches the value extracted from the lower-layer encapsulation contained in the AVP matches the value extracted from the
header corresponding to the device identifier type contained in lower-layer encapsulation header corresponding to the device
the AVP (check performed by PAA only). Note that a Device-Id AVP identifier type contained in the AVP (check performed by the PAA
carries the PaC's device identifier in messages from PaC to PAA only). Note that a Device-Id AVP carries the device identifier of
and EP(s)' device identifier in messages from PAA to PaC. the PaC in messages from the PaC to the PAA and the device
identifier(s) of the EP(s) in messages from the PAA to the PaC.
o When an IP-Address AVP is received in a message, the AVP is valid o When an IP-Address AVP is received in a message, the AVP is valid
if the IP address matches the source address in the IP header. if the IP address matches the source address in the IP header.
Invalid messages MUST be discarded in order to provide robustness Invalid messages MUST be discarded in order to provide robustness
against DoS attacks. In addition, an error notification message MAY against DoS attacks. In addition, an error notification message MAY
be returned to the sender. See Section 5.7 for details. be returned to the sender. See Section 5.10 for details.
5.6 PANA Security Association
A PANA SA is created as an attribute of a PANA session when EAP
authentication succeeds with a creation of a AAA-Key. A PANA SA is
not created when the PANA authentication fails or no AAA-Key is
produced by any EAP authentication method. In the case where two EAP
authentications are performed in sequence in a single PANA
authentication phase, it is possible that two AAA-Keys are derived.
If this happens, the PANA SA MUST be generated from both AAA-Keys.
When a new AAA-Key is derived as a result of EAP-based
re-authentication, any key derived from the old AAA-Key MUST be
updated to a new one that is derived from the new AAA-Key. In order
to distinguish the new AAA-Key from old ones, one Key-Id AVP MUST be
carried in PANA-Bind-Request and PANA-Bind-Answer messages or
PANA-FirstAuth-End-Request and PANA-FirstAuth-End-Answer messages at
the end of the EAP authentication which resulted in deriving a new
AAA-Key. The Key-Id AVP is of type Unsigned32 and MUST contain a
value that uniquely identifies the AAA-Key within the PANA session.
The PANA-Bind-Answer message (or the PANA-FirstAuth-End-Answer
message) sent in response to a PANA-Bind-Request message (or a
PANA-FirstAuth-End-Request message) with a Key-Id AVP MUST contain a
Key-Id AVP with the same AAA-Key identifier carried in the request.
PANA-Bind-Request, PANA-Bind-Answer, PANA-FirstAuth-End-Request and
PANA-FirstAuth-End-Answer messages with a Key-Id AVP MUST also carry
a MAC AVP whose value is computed by using the new PANA-MAC-KEY
derived from the new AAA-Key (or the new pair of AAA-Keys when the
PANA_MAC_KEY is derived from two AAA-Keys). Although the
specification does not mandate a particular method for calculation of
Key-Id AVP value, a simple method is to use monotonically increasing
numbers.
The created PANA SA is deleted when the corresponding PANA session is
deleted. The lifetime of the PANA SA is the same as the lifetime of
the PANA session for simplicity.
PANA SA attributes as well as PANA session attributes are listed
below:
PANA Session attributes:
* Session-Id
* Device-Id of PaC
* IP address of PaC (may be the same as the Device-Id of PaC)
* IP address of PAA
* List of device identifiers of EPs
* Sequence number of the last transmitted request
* Sequence number of the last received request
* Last transmitted message payload
* Retransmission interval
* Session lifetime
* Protection-Capability
* PANA SA attributes:
+ Nonce generated by PaC (PaC_nonce)
+ Nonce generated by PAA (PAA_nonce)
+ AAA-Key
+ AAA-Key Identifier
+ PANA_MAC_KEY
The PANA_MAC_KEY is used to integrity protect PANA messages and
derived from AAA-Key(s). When two AAA-Keys (AAA-Key1 and AAA-Key2)
are generated as a result of double EAP authentication (see Section
4.2) the compound AAA-Key can be computed as follows ('|' indicates
concatenation):
AAA-Key = AAA-Key1 | AAA-Key2
The PANA_MAC_KEY is computed in the following way:
PANA_MAC_KEY = The first N bits of
HMAC_SHA1(AAA-Key, PaC_nonce | PAA_nonce | Session-ID)
where the value of N depends on the integrity protection algorithm in
use, i.e., N=160 for HMAC-SHA1. The length of AAA-Key MUST be N bits
or longer. See Section Section 5.4 for the detailed usage of the
PANA_MAC_KEY.
5.7 Error Handling
A PANA-Error-Request message MAY be sent by either the PaC or the PAA
when a badly formed PANA message is received or in case of other
errors. The receiver of this request MUST respond with a
PANA-Error-Answer message. If the cause of this error message was a
request message (e.g., PANA-PAA-Discover or *-Request), then the
request MAY be retransmitted immediately without waiting for its
retransmission timer to go off. If the cause of the error was a
response message, the receiver of the PANA-Error-Request message
SHOULD NOT resend the same response until it receives the next
request.
To defend against DoS attacks a timer MAY be used. One (1) error
notification is sent to each different sender each N seconds. N is a
configurable parameter.
When an error message is sent unprotected with a MAC AVP and the
lower-layer is insecure, the error message is treated as an
informational message. The receiver of such an error message MUST
NOT change its state unless the error persists and the PANA session
is not making any progress.
5.8 Device ID Choice 5.6 Device ID Choice
The device identifier used in the context of PANA can be an IP The device identifier used in the context of PANA can be an IP
address, a MAC address, or an identifier that is not carried in data address, a MAC address, or an identifier that is not carried in data
packets but has local significance in identifying a connected host packets but has local significance in identifying a connected device
(e.g., circuit id, PPP interface id). The last type of identifiers (e.g., circuit id, PPP interface id). The last type of identifiers
are commonly used in point-to-point links where MAC addresses are not are commonly used in point-to-point links where MAC addresses are not
available and lower-layers are already physically or available and lower-layers are already physically or
cryptographically secured. cryptographically secured.
It is assumed that the PAA knows the link type and the security It is assumed that the PAA knows the link type and the security
mechanisms being provided or required on the access network (e.g., mechanisms being provided or required on the access network (e.g.,
based on physical security, link-layer ciphers enabled before or based on physical security, link-layer ciphers enabled before or
after PANA, or IPsec). Based on that information, the PAA can decide after PANA, or IPsec). Based on that information, the PAA can decide
what type of EP device id will be used when running PANA with the what type of EP device id will be used when running PANA with the
client. When IPsec-based security [I-D.ietf-pana-ipsec] is the client. When IPsec-based security [I-D.ietf-pana-ipsec] is the
choice of access control, the PAA SHOULD provide IP address(es) as choice of access control, the PAA SHOULD provide IP address(es) as
EP(s)' device ID, and expect the PaC to provide its IP address in EP(s)' device ID, and expect the PaC to provide its IP address in
return. In case IPsec is not used, MAC addresses are used as device return. In case IPsec is not used, MAC addresses are used as device
IDs when available. If non-IPsec access control is enabled, and a identifiers when available. If non-IPsec access control is enabled,
MAC address is not available, device ID exchange does not occur and a MAC address is not available, device ID exchange does not occur
within PANA. Instead, peers rely on lower-layers to provide within PANA. Instead, peers rely on lower-layers to provide
locally-significant identifiers along with received PANA packets. locally-significant identifiers along with received PANA messages.
5.9 Updating PaC' Address 5.7 PaC Updating its IP Address
A PaC's IP address can change in certain situations. For example, A PaC's IP address can change in certain situations. For example,
the PANA framework [I-D.ietf-pana-framework] describes a case in the PANA framework [I-D.ietf-pana-framework] describes a case in
which a PaC replaces a pre-PANA address (PRPA) with a post-PANA which a PaC replaces a pre-PANA address (PRPA) with a post-PANA
address (POPA), and the PaC and PAA create host routes to each other address (POPA), and the PaC and PAA create host routes to each other
in order to maintain on-link communication based on the POPA. The in order to maintain on-link communication based on the POPA. The
PAA needs to be notified about the change of PaC address. PAA needs to be notified about the change of PaC address.
After the PaC has changed its address, it MUST send a After the PaC has changed its address, it MUST send a
PANA-Update-Request message to the PAA. The message MUST carry the PANA-Update-Request message to the PAA. The message MUST carry the
new PaC address in an IP-Address AVP. If the address contained in new PaC address in an IP-Address AVP. If the address contained in
the request is invalid, the PAA MUST send a PANA-Error message with the request is invalid, the PAA MUST send a PANA-Error message with a
the result code PANA_INVALID_IP_ADDRESS. Otherwise, the PAA MUST result code PANA_INVALID_IP_ADDRESS. Otherwise, the PAA MUST update
update the PANA session with the new PaC address and return a the PANA session with the new PaC address and return a
PANA-Update-Answer message. If there is an established PANA SA, both PANA-Update-Answer message. If there is an established PANA SA, both
PANA-Update-Request and PANA-Update-Answer messages MUST be protected PANA-Update-Request and PANA-Update-Answer messages MUST be protected
with a MAC AVP. with a MAC AVP.
5.10 Session Lifetime 5.8 Session Lifetime
The authentication phase determines the PANA session lifetime when
the network access authorization succeeds. The Session-Lifetime AVP
MAY be optionally included in the PANA-Bind-Request message to inform
PaC about the valid lifetime of the PANA session. It MUST be ignored
when included in other PANA messages. When there are multiple EAP
authentication taking place, this AVP SHOULD be included after the
final authentication.
The lifetime is a non-negotiable parameter that can be used by PaC to The authentication and authorization phase determines the PANA
manage PANA-related state. PaC does not have to perform any actions session lifetime when the network access authorization succeeds. The
when the lifetime expires, other than optionally purging local state. Session-Lifetime AVP MAY be optionally included in the
PANA-Bind-Request message to inform the PaC about the valid lifetime
of the PANA session. It MUST be ignored when included in other PANA
messages.
PAA SHOULD initiate EAP authentication before the current session The lifetime is a non-negotiable parameter that can be used by the
lifetime expires. PaC to manage PANA-related state. The PaC does not have to perform
any actions when the lifetime expires, other than optionally purging
local state. The PAA SHOULD initiate the PANA re-authentication
phase before the current session lifetime expires.
PaC and PAA MAY optionally rely on lower-layer indications to The PaC and PAA MAY optionally rely on lower-layer indications to
expedite the detection of a disconnected peer. Availability and expedite the detection of a disconnected peer. Availability and
reliability of such indications depend on the specific access reliability of such indications depend on the specific access
technologies. PANA peer can use PANA-Ping-Request message to verify technologies. A PANA peer can use the PANA-Ping exchange to verify
the disconnection before taking an action. the disconnection before taking an action.
The session lifetime parameter is not related to the transmission of The session lifetime parameter is not related to the transmission of
PANA-Ping-Request messages. These messages can be used for PANA-Ping-Request messages. These messages can be used for
asynchronously verifying the liveness of the peer. The decision to asynchronously verifying the liveness of the peer. The decision to
send PANA-Ping-Request message is taken locally and does not require send a PANA-Ping-Request message is taken locally and does not
coordination between the peers. require coordination between the peers.
5.11 Network Selection
In a discovery and handshake phase, a PANA-Start-Request message sent
from the PAA MAY contain zero or one NAP-Information AVP and zero or
more ISP-Information AVPs to advertise the information on the NAP
and/or ISPs. The PaC MAY indicate its choice of ISP by including an
ISP-Information AVP in the PANA-Start-Answer message. When a AAA
backend is used, the identity of the destination AAA server or realm
MUST be determined based on the explicitly chosen ISP. When the
ISP-Information AVP is not present, the access network MAY rely on
the client identifier carried in the EAP authentication method to
make this determination. The PaC can choose an ISP and contain an
ISP-Information AVP for the chosen ISP in a PANA-Start-Answer message
even when there is no ISP-Information AVP contained in the
PANA-Start-Request message.
5.12 Separate NAP and ISP Authentication
PANA allows running at most two EAP sessions in sequence in an
authentication phase to support separate NAP and ISP authentication
as described in next sections. Currently, running multiple EAP
sessions in sequence in an authentication phase is designed only for
separate NAP and ISP authentication. It is not for running arbitrary
number of EAP sessions in sequence, or giving the PaC another chance
to try another EAP authentication method within an integrated NAP and
ISP authentication when an EAP authentication method fails. Within
separate NAP and ISP authentication, the NAP authentication and the
ISP authentication are considered completely independent. Presence
or success of one should not effect the other. Making a network
access authorization decision based on the success or failure of each
authentication is a network policy issue.
5.12.1 Negotiating Separate NAP and ISP Authentication
When the PaC and PAA negotiates in the discovery and handshake phase
to perform separate NAP and ISP authentication, the PaC and the PAA
operate in the following way in addition to the behavior defined in
Section 4.1
In the discovery and handshake phase, the PAA MAY enable separate NAP
and ISP authentication ([I-D.ietf-pana-framework]) by setting the
S-flag of the message header of the PANA-Start-Request.
If the S-flag of the received PANA-Start-Request message is not set,
the PaC MUST NOT set the S-flag in the PANA-Start-Answer message sent
back to the PAA.
If the S-flag of the received PANA-Start-Request message is set, the
PaC can indicate its desire to perform separate NAP and ISP
authentication by setting the S-flag in the PANA-Start-Answer
message. If the S-flag in the PANA-Start-Answer message is not set,
only one authentication is performed and the processing occurs as
described in Section 4.1. If the S-flag in the PANA-Start-Answer
message is set, the determination of the destination AAA server or
realm for ISP authentication is performed as described in Section
5.11. In addition, where backend AAA servers are used for NAP
authentication, the NAP is considered the ultimate AAA realm, and the
destination AAA server for this authentication is determined entirely
by the local configuration on the access server hosting the PAA
(NAS).
When the S-flag is set in a PANA-Start-Request message, the initial
EAP Request MUST NOT be carried in the PANA-Start-Request message.
(If the initial EAP Request were contained in the PANA-Start-Request
message during the S-flag negotiation, the PaC cannot tell whether
the EAP Request is for NAP authentication or ISP authentication.)
5.12.2 Execution of Separate NAP and ISP Authentication
When the PaC and PAA have negotiated in the discovery and handshake
phase to perform separate NAP and ISP authentication, the PaC and the
PAA operate in the following way in addition to the behavior defined
in Section 4.2
o The S-flag of PANA-Auth-Request and PANA-Auth-Answer messages MUST
be set.
o An EAP Success/Failure message is carried in a
PANA-FirstAuth-End-Request (PFER) message as well as a
PANA-Bind-Request (PBR) message. The PANA-FirstAuth-End-Request
message MUST be used at the end of the first EAP authentication
and the PANA-Bind-Request MUST be used for the second EAP
authentication. The PANA-FirstAuth-End-Request messages MUST be
acknowledged with a PANA-FirstAuth-End-Answer (PFEA) message.
o If the first EAP authentication has failed, the PAA can choose not
to perform the second EAP authentication by clearing the S-flag of
the PANA-FirstAuth-End-Request message. In this case, the S-flag
of the PANA-FirstAuth-End-Answer message sent by the PaC MUST be
cleared. If the S-flag of the PANA-FirstAuth-End-Request message
is set when the first EAP authentication has failed, the PaC can
choose not to perform the second EAP authentication by clearing
the S-flag of the PANA-FirstAuth-End-Answer message. If the first
EAP authentication failed and the S-flag is not set in the
PANA-FirstAuth-End-Answer message as a result of those operations,
the PANA session MUST be immediately deleted. Otherwise, the
second EAP authentication MUST be performed.
o The PAA determines the execution order of NAP authentication and
ISP authentication. In this case, the PAA can indicate which
authentication (NAP authentication or ISP authentication) is
currently occurring by using N-flag in the PANA message header.
When NAP authentication is being performed, the N-flag MUST be
set. When ISP authentication is being performed, the N-flag MUST
NOT be set. The N-flag MUST NOT be set when S-flag is not set.
5.12.3 AAA-Key Calculation
When the PaC and PAA have negotiated in the discovery and handshake
phase to perform separate NAP and ISP authentication, if the
lower-layer is insecure, the two EAP authentication methods used in
the separate authentication MUST be capable of deriving keys. In
this case, if the first EAP authentication is successful, the
PANA-FirstAuth-End-Request and PANA-FirstAuth-End-Answer messages as
well as PANA-Auth-Request and PANA-Auth-Answer messages in the second
EAP authentication MUST be protected with the key derived from the
AAA-Key for the first EAP authentication. The PANA-Bind-Request and
PANA-Bind-Answer messages and all subsequent PANA messages exchanged
in authorized phase, re-authentication phase and termination phase
MUST be protected either with the AAA-Key for the first EAP
authentication if the first EAP authentication succeeds and the
second EAP authentication fails, or with the AAA-Key for the second
EAP authentication if the first EAP authentication fails and the
second EAP authentication succeeds, or with the compound AAA-Key
derived from the two AAA-Keys, one for the first EAP authentication
and the other from the second EAP authentication, if both the first
and second EAP authentications succeed.
5.12.4 Re-authentication
When separate ISP and NAP authentication is performed, it is possible When separate ISP and NAP authentication is performed, it is possible
that different authorization lifetime values are associated with the that different authorization lifetime values are associated with the
two authentications. In this case, the smaller authorization two EAP authentication sessions. In this case, the smaller
lifetime value MUST be used for calculating the PANA Session-Lifetime authorization lifetime value MUST be used for calculating the PANA
value. As a result, when entering a re-authentication phase, both Session-Lifetime value. As a result, both NAP and ISP authentication
NAP and ISP authentication will be performed in the same will be performed in the re-authentication phase.
re-authentication phase.
5.12.5 Example Sequence
A PANA message sequence with separate NAP and ISP authentication is
illustrated in Figure 9. The example assumes the following scenario:
o The PaC initiates the discovery and handshake phase.
o The PAA offers separate NAP and ISP authentication, as well as a
choice of ISP from "ISP1" and "ISP2". The PaC accepts the offer
from PAA, with choosing "ISP1" as the ISP.
o NAP authentication and ISP authentication is performed in this
order in authentication phase.
o An EAP authentication method with a single round trip is used in
each EAP sequence.
o After a PANA SA is established, all messages are integrity and
replay protected with MAC AVPs.
o Authorization, re-authentication and termination phases are not
shown.
PaC PAA Message(seqno)[AVPs]
-----------------------------------------------------
// Discovery and handshake phase
-----> PANA-PAA-Discover(0)
<----- PANA-Start-Request(x) // S-flag set
[Nonce, Cookie,
ISP-Information("ISP1"),
ISP-Information("ISP2"),
NAP-Information("MyNAP")]
-----> PANA-Start-Answer(x) // S-flag set
[Nonce, Cookie, // PaC chooses "ISP1"
ISP-Information("ISP1")]
// Authentication phase
<----- PANA-Auth-Request(x+1) // NAP authentication
[Session-Id, EAP{Request}] // S- and N-flags set
-----> PANA-Auth-Answer(x+1) // S- and N-flags set
[Session-Id] // No piggybacking
-----> PANA-Auth-Request(y) // S- and N-flags set
[Session-Id, EAP{Response}]
<----- PANA-Auth-Answer(y)[Session-Id] // S- and N-flags set
<----- PANA-Auth-Request(x+2) // S- and N-flags set
[Session-Id, EAP{Request}]
-----> PANA-Auth-Answer(x+2) // S- and N-flags set
[Session-Id, EAP{Response}] // Piggybacking
<----- PANA-FirstAuth-End-Request(x+3) // S- and N-flags set
[Session-Id, EAP{Success}, Key-Id, MAC]
-----> PANA-FirstAuth-End-Answer(x+3) // S- and N-flags set
[Session-Id, Key-Id, MAC]
<----- PANA-Auth-Request(x+4) // ISP authentication
[Session-Id, EAP{Request}, MAC] // S-flag set
-----> PANA-Auth-Answer(x+4) // S-flag set
[Session-Id, MAC] // No piggybacking
-----> PANA-Auth-Request(y+1) // S-flag set
[Session-Id, EAP{Response}, MAC]
<----- PANA-Auth-Answer(y+1) // S-flag set
[Session-Id, MAC]
<----- PANA-Auth-Request(x+5) // S-flag set
[Session-Id, EAP{Request}, MAC]
-----> PANA-Auth-Answer(x+5) // S-flag set
[Session-Id, EAP{Response}, MAC] // Piggybacking
<----- PANA-Bind-Request(x+6) // S-flag set
[Session-Id, EAP{Success}, Device-Id,
IP-Address, Key-Id, Lifetime,
Protection-Cap., PPAC, MAC]
-----> PANA-Bind-Answer(x+6) // S-flag set
[Session-Id, Device-Id, Key-Id,
PPAC, MAC]
Figure 9: A Complete Message Sequence for Separate NAP and ISP
Authentication
6. Security and Mobility
6.1 PANA Security Association Establishment
When PANA is used over an already established secure channel, such as
physically secured wires or ciphered link-layers, we can reasonably
assume that man-in-the-middle attacks or service theft is not
possible. See [I-D.ietf-pana-threats-eval] for a detailed
discussion.
In environments where no secure channel prior to the PANA execution
is available, PANA needs to protect itself against a number of
attacks. The device identifier that is used during the
authentication needs to be verified at the end of the authentication
to prevent service theft and DoS attacks. Additionally, a free
loader should be prevented from spoofing data packets by using the
device identifier of an already authorized legitimate client. Both
of these requirements necessitate generation of a security
association between the PaC and the PAA at the end of the
authentication. This can only be done when the authentication method
used can generate session keys. Use of session keys can prevent
attacks which would otherwise be very easy to launch by eavesdropping
on and spoofing traffic over an insecure link.
The EAP method provided session key is transported to the PAA (if
necessary) and is subsequently input to the creation of the PANA SA.
Applying the PANA SA to the messages exchanged during the final PANA
handshake provides implicit key confirmation to both the PAA and the
PaC. Implicit key confirmation shows both, the PaC and the PAA, that
they possess the unique and fresh session key.
Protecting the final PANA handshake also ensures that the device
identifier (and other information) cannot be modified by an
adversary. Further usage of the keying material is discussed in
[I-D.ietf-pana-framework].
6.2 Mobility
A mobile PaC's network access authentication performance can be
enhanced by deploying a context-transfer-based mechanism, where some
session attributes are transferred from the previous PAA to the new
one in order to avoid performing a full EAP authentication (reactive
approach). Additional mechanisms that are based on the proactive AAA
state establishment at one or more candidate PAAs may be developed in
the future [I-D.irtf-aaaarch-handoff]. The details of a
context-transfer-based mechanism is provided in this section.
Upon changing its point of attachment, a PaC that wants to quickly
resume its ongoing PANA session without running EAP MAY send its
unexpired PANA session identifier in its PANA-Start-Answer message.
Along with the Session-Id AVP, a MAC AVP MUST be included in this
message. The MAC AVP is computed by using the PANA_MAC_KEY shared
between the PaC and its previous PAA that has an unexpired PANA
session with the PaC. This action signals PaC's desire to perform
the mobility optimization. In the absence of a Session-Id AVP in
this message, the PANA session takes its usual course (i.e.,
EAP-based authentication is performed).
If a PAA receives a session identifier in the PANA-Start-Answer 5.9 Network Selection
message, and it is configured to enable this optimization, it SHOULD
retrieve the PANA session attributes from the previous PAA. Current
PAA determines the identity of the previous PAA by looking at the
DiameterIdentity part of the PANA session identifier. The MAC AVP
can only be verified by the previous PAA, therefore a copy of the
PANA message SHOULD be provided to the previous PAA. The mechanism
required to send a copy of the PANA-Start-Answer message from current
PAA to the previous PAA, and retrieve the session attributes is
outside the scope of PANA protocol. The Context Transfer Protocol
[I-D.ietf-seamoby-ctp] might be useful for this purpose.
When the previous or current PAA is not configured to enable this The PANA discovery and handshake phase allows the PaC to learn
optimization, the current PAA can not retrieve the PANA session identity of the NAP and a list of ISPs that are available through the
attributes, or the PANA session has already expired (i.e., session NAP. The PaC can not only learn the ISPs but also convey the
lifetime is zero), the PAA MUST send the PANA-Auth-Request message selected ISP explicitly during the handshake phase. The PAA is
with a new session identifier and let the PANA exchange take its assumed to be pre-configured with the information of ISPs that are
usual course. This action will engage EAP-based authentication and served by the NAP.
create a fresh PANA session from scratch.
In case the current PAA can retrieve the on-going PANA session A PANA-Start-Request message sent from the PAA MAY contain zero or
attributes from the previous PAA, the PANA session continues with a one NAP-Information AVP, and zero or more ISP-Information AVPs. The
PANA-Bind exchange. PaC MAY indicate its choice of ISP by including an ISP-Information
AVP in the PANA-Start-Answer message. The PaC MAY convey its ISP
even when there is no ISP-Information AVP contained in the
PANA-Start-Request message. The PaC can do that when it is
pre-configured with ISP information.
As part of the context transfer, an intermediate AAA-Key material is In the absence of an ISP explicitly selected and conveyed by the PaC,
provided by the previous PAA to the current PAA. ISP selection is typically performed based on the client identifier
(e.g., using the realm portion of an NAI carried in EAP method). A
backend AAA protocol (e.g., RADIUS) will run between the AAA client
on the PAA and a AAA server in the selected ISP domain.
AAA-Key-int = The first N bits of The PANA-based ISP selection mechanism dictates the next-hop AAA
HMAC-SHA1(AAA-Key, DiameterIdentity | Session-ID) proxy on the PAA. If the NAP requires all AAA traffic to go through
its local AAA proxy, it may have to rely on a mechanism to relay the
selected ISP information from PAA (AAA client) to the local AAA
proxy. The local AAA proxy can forward the AAA traffic to the
selected ISP domain upon processing. Further details, including how
the AAA client relays AAA routing information to the AAA proxy, are
outside the scope of PANA.
The value of N depends on the integrity protection algorithm in use, An alternative ISP discovery mechanism is outlined in
i.e., N=160 for HMAC-SHA1. DiameterIdentity is the identifier of the [I-D.adrangi-eap-network-discovery] which suggests advertising ISP
current PAA. Session-ID is the identifier of the PaC's PANA session information in-band with the ongoing EAP method execution.
with the previous PAA. Deployments using the PANA's built-in ISP discovery mechanism need
not use the other mechanism.
The current PAA and PaC compute the new AAA-Key by using the nonce 5.10 Error Handling
values and the AAA-Key-int.
AAA-Key-new = The first N bits of A PANA-Error-Request message MAY be sent by either the PaC or the PAA
HMAC-SHA1(AAA-Key-int, PaC_nonce | PAA_nonce) when a badly formed PANA message is received or in case of other
errors. The receiver of this request MUST respond with a
PANA-Error-Answer message. If the cause of this error message was a
request message (e.g., PANA-PAA-Discover or *-Request), then the
request MAY be retransmitted immediately without waiting for its
retransmission timer to go off. If the cause of the error was a
response message, the receiver of the PANA-Error-Request message
SHOULD NOT resend the same response until it receives the next
request.
New PANA_MAC_KEY is computed based on the algorithm described in Erroneous PANA messages may be exploited by adversaries to launch DoS
Section 5.6, by using the new AAA-Key and the new Session-ID assigned attacks on the victims. Unless the PaC or PAA rate-limits the
by the current PAA. The MAC AVP contained in the PANA-Bind-Request generated PANA-Error-Request messages it may be overburdened by
and PANA-Bind-Answer messages MUST be generated and verified by using having to respond to bogus messages. Limiting the number of error
the new PANA_MAC_KEY. The Session-ID AVP MUST include a new session notifications sent to a given peer during a (configurable) period of
identifier assigned by the current PAA. A new PANA session is time may be useful.
created upon successful completion of this exchange.
Note that correct operation of this optimization relies on many When an error message is sent unprotected (i.e., no MAC AVP) and the
factors, including applicability of authorization state from one lower-layer is insecure, the error message is treated as an
network attachment to another. [I-D.ietf-eap-keying] identifies this informational message. The receiver of such an error message MUST
operation as "fast handoff" and provides deployment considerations. NOT change its state unless the error persists and the PANA session
Operators are recommended to take those guidelines into account when is not making any progress.
using this optimization in their networks.
7. PANA Headers and Formats 6. PANA Headers and Formats
This section defines message formats for PANA protocol. This section defines message formats for PANA protocol.
7.1 IP and UDP Headers 6.1 IP and UDP Headers
The Hop Limit (or TTL) field of the IP header MUST be set to 255. The Hop Limit (or TTL) field of the IP header MUST be set to 255.
When a PANA-PAA-Discover message is multicast, IP destination address When a PANA-PAA-Discover message is multicast, IP destination address
of the message is set to a well-known link-local multicast address of the message is set to a well-known link-local multicast address
(TBD). A PANA-PAA-Discover message MAY be unicast in some cases as (TBD). A PANA-PAA-Discover message MAY be unicast in some cases as
specified in Section 4.1. Any other PANA packet is unicast between specified in Section 4.2. Any other PANA packet is unicast between
the PaC and the PAA. The source and destination addresses SHOULD be the PaC and the PAA. The source and destination addresses SHOULD be
set to the addresses on the interfaces from which the message will be set to the addresses on the interfaces from which the message will be
sent and received, respectively. sent and received, respectively.
When the PANA packet is sent in response to a request, the UDP source When the PANA packet is sent in response to a request, the UDP source
and destination ports of the response packet MUST be copied from the and destination ports of the response packet MUST be copied from the
destination and source ports of the request packet, respectively. destination and source ports of the request packet, respectively.
The destination port of an unsolicited PANA packet MUST be set to an The destination port of an unsolicited PANA packet MUST be set to an
assigned value (TBD), and the source port MUST be set to a value assigned value (TBD), and the source port MUST be set to a value
chosen by the sender. chosen by the sender.
7.2 PANA Header The maximum PANA packet size is limited by the maximum UDP payload.
6.2 PANA Header
A summary of the PANA header format is shown below. The fields are A summary of the PANA header format is shown below. The fields are
transmitted in network byte order. transmitted in network byte order.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Version | Reserved | Message Length | | Version | Reserved | Message Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flags | Message Type | | Flags | Message Type |
skipping to change at page 36, line 17 skipping to change at page 34, line 18
This 8-bit field is reserved for future use, and MUST be set to This 8-bit field is reserved for future use, and MUST be set to
zero, and ignored by the receiver. zero, and ignored by the receiver.
Message Length Message Length
The Message Length field is three octets and indicates the length The Message Length field is three octets and indicates the length
of the PANA message including the header fields. of the PANA message including the header fields.
Flags Flags
The Flags field is eight bits. The following bits are assigned: The Flags field is two octets. The following bits are assigned:
0 1 0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|R S N r r r r r r r r r r r r r| |R S N r r r r r r r r r r r r r|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
R(equest) R(equest)
If set, the message is a request. If cleared, the message is If set, the message is a request. If cleared, the message is
an answer. an answer.
S(eparate) S(eparate)
When the S-flag is set in a PANA-Start-Request message it When the S-flag is set in a PANA-Start-Request message it
indicates that PAA is willing to offer separate NAP and ISP indicates that PAA is willing to offer separate NAP and ISP
authentication. When the S-flag is set in a PANA-Start-Answer authentication. When the S-flag is set in a PANA-Start-Answer
message it indicates that the PaC accepts on performing message it indicates that the PaC accepts on performing
separate NAP and ISP authentication. When the S-flag is set in separate NAP and ISP authentication. The PaC may also respond
a PANA-Auth-Request/Answer, PANA-FirstAuth-End-Request/Answer with the S-flag not set which implies the PaC has chosen to
and PANA-Bind-Request/Answer messages it indicates that authenticate with the ISP only. When the S-flag is set in a
separate NAP and ISP authentication is being performed in the PANA-Auth-Request/Answer, PANA-FirstAuth-End-Request/Answer and
authentication phase. For other cases, S-flag MUST NOT be set. PANA-Bind-Request/Answer messages it indicates that separate
NAP and ISP authentication is being performed in the
authentication and authorization phase. For other cases,
S-flag MUST NOT be set.
N(AP authentication) N(AP authentication)
When the N-flag is set in a PANA-Auth-Request message, it When the N-flag is set in a PANA-Auth-Request message, it
indicates that the current EAP authentication is for NAP indicates that the current EAP authentication is for NAP
authentication. When the N-flag is unset in a authentication. When the N-flag is unset in a
PANA-Auth-Request message, it indicates that the current EAP PANA-Auth-Request message, it indicates that the current EAP
authentication is for ISP authentication. The PaC MUST copy authentication is for ISP authentication. The PaC MUST copy
the value of the flag in its requests from the last received the value of the flag in its requests from the last received
request of the PAA. The value of the flag on an answer MUST be request of the PAA. The value of the flag on an answer MUST be
copied from the request. The N-flag MUST NOT be set when copied from the request. The N-flag MUST NOT be set when
S-flag is not set. S-flag is not set.
skipping to change at page 37, line 8 skipping to change at page 35, line 16
authentication. When the N-flag is unset in a authentication. When the N-flag is unset in a
PANA-Auth-Request message, it indicates that the current EAP PANA-Auth-Request message, it indicates that the current EAP
authentication is for ISP authentication. The PaC MUST copy authentication is for ISP authentication. The PaC MUST copy
the value of the flag in its requests from the last received the value of the flag in its requests from the last received
request of the PAA. The value of the flag on an answer MUST be request of the PAA. The value of the flag on an answer MUST be
copied from the request. The N-flag MUST NOT be set when copied from the request. The N-flag MUST NOT be set when
S-flag is not set. S-flag is not set.
r(eserved) r(eserved)
these flag bits are reserved for future use, and MUST be set to These flag bits are reserved for future use, and MUST be set to
zero, and ignored by the receiver. zero, and ignored by the receiver.
Message Type Message Type
The Message Type field is two octets, and is used in order to The Message Type field is two octets, and is used in order to
communicate the message type with the message. The 16-bit address communicate the message type with the message. The 16-bit address
space is managed by IANA [ianaweb]. PANA uses its own address space is managed by IANA [ianaweb]. PANA uses its own address
space for this field. space for this field.
Sequence Number Sequence Number
The Sequence Number field contains a 32 bit value. The Sequence Number field contains a 32 bit value.
AVPs AVPs
AVPs are a method of encapsulating information relevant to the AVPs are a method of encapsulating information relevant to the
PANA message. See section Section 7.3 for more information on PANA message. See section Section 6.3 for more information on
AVPs. AVPs.
7.3 AVP Header 6.3 AVP Header
Each AVP of type OctetString MUST be padded to align on a 32-bit Each AVP of type OctetString MUST be padded to align on a 32-bit
boundary, while other AVP types align naturally. A number of boundary, while other AVP types align naturally. A number of
zero-valued bytes are added to the end of the AVP Data field till a zero-valued bytes are added to the end of the AVP Data field till a
word boundary is reached. The length of the padding is not reflected word boundary is reached. The length of the padding is not reflected
in the AVP Length field [RFC3588]. in the AVP Length field [RFC3588].
The fields in the AVP header MUST be sent in network byte order. The The fields in the AVP header are sent in network byte order. The
format of the header is: format of the header is:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AVP Code | AVP Flags | | AVP Code | AVP Flags |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AVP Length | Reserved | | AVP Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Vendor-Id (opt) | | Vendor-Id (opt) |
skipping to change at page 38, line 26 skipping to change at page 36, line 33
0 1 0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|V M r r r r r r r r r r r r r r| |V M r r r r r r r r r r r r r r|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
M(andatory) M(andatory)
The 'M' Bit, known as the Mandatory bit, indicates whether The 'M' Bit, known as the Mandatory bit, indicates whether
support of the AVP is required. support of the AVP is required.
If an AVP with the 'M' bit set is received by the PaC or PAA
and either the AVP or its value is unrecognized, the message
MUST be rejected and the receiver MUST send a
PANA-Error-Request message. If the AVP was unrecognized the
PANA-Error-Request message result code MUST be
PANA_AVP_UNSUPPORTED. If the AVP value was unrecognized the
PANA-Error-Request message result code MUST be
PANA_INVALID_AVP_DATA. In either case the PANA-Error-Request
message MUST carry a Failed-AVP AVP containing the offending
mandatory AVP.
AVPs with the 'M' bit cleared are informational only and a
receiver that receives a message with such an AVP that is not
supported, or whose value is not supported, MAY simply ignore
the AVP.
V(endor) V(endor)
The 'V' bit, known as the Vendor-Specific bit, indicates The 'V' bit, known as the Vendor-Specific bit, indicates
whether the optional Vendor-Id field is present in the AVP whether the optional Vendor-Id field is present in the AVP
header. header. When set the AVP Code belongs to the specific vendor
code address space.
r(eserved) r(eserved)
These flag bits are reserved for future use, and MUST be set to These flag bits are reserved for future use, and MUST be set to
zero, and ignored by the receiver. zero, and ignored by the receiver.
Unless otherwise noted, AVPs defined in this document will have
the following default AVP Flags field settings: The 'M' bit MUST
be set. The 'V' bit MUST NOT be set.
AVP Length AVP Length
The AVP Length field is four octets, and indicates the number of The AVP Length field is four octets, and indicates the number of
octets in this AVP including the AVP Code, AVP Length, AVP Flags, octets in this AVP including the AVP Code, AVP Length, AVP Flags,
and the AVP data. and the AVP data.
Reserved Reserved
This two-octet field is reserved for future use, and MUST be set This two-octet field is reserved for future use, and MUST be set
skipping to change at page 40, line 5 skipping to change at page 38, line 5
Vendor-Id along with their privately managed AVP address space, Vendor-Id along with their privately managed AVP address space,
guaranteeing that they will not collide with any other vendor's guaranteeing that they will not collide with any other vendor's
vendor-specific AVP(s), nor with future IETF applications. vendor-specific AVP(s), nor with future IETF applications.
Data Data
The Data field is zero or more octets and contains information The Data field is zero or more octets and contains information
specific to the Attribute. The format and length of the Data specific to the Attribute. The format and length of the Data
field is determined by the AVP Code and AVP Length fields. field is determined by the AVP Code and AVP Length fields.
8. PANA Messages, Message Specifications and AVPs 7. PANA Messages, Message Specifications and AVPs
8.1 PANA Messages 7.1 PANA Messages
Figure 10 lists all PANA messages defined in this document. Each Request/Answer message pair is assigned a message ID, and the
sub-type (i.e., request or answer) is identified via the 'R' bit in
the Message Flags field of the PANA header.
Message Direction: PaC---PAA Every PANA message MUST contain a message ID in its header's
---------------------------------------- Message-Id field, which is used to determine the action that is to be
PANA-PAA-Discover --------> taken for a particular message. Figure 9 lists all PANA messages
defined in this document:
PANA-Start-Request <-------- Message-Name Abbrev. ID PaC<->PAA Ref.
PANA-Start-Answer --------> -----------------------------------------------------------
PANA-PAA-Discover PDI 1 --------> 7.2.1
PANA-Start-Request PSR 2 <-------- 7.2.2
PANA-Start-Answer PSA 2 --------> 7.2.3
PANA-Auth-Request PAR 3 <-------> 7.2.4
PANA-Auth-Answer PAN 3 <-------> 7.2.5
PANA-Reauth-Request PRAR 4 --------> 7.2.6
PANA-Reauth-Answer PRAA 4 <-------- 7.2.7
PANA-Bind-Request PBR 5 <-------- 7.2.8
PANA-Bind-Answer PBA 5 --------> 7.2.9
PANA-Ping-Request PPR 6 <-------> 7.2.10
PANA-Ping-Answer PPA 6 <-------> 7.2.11
PANA-Termination-Request PTR 7 <-------> 7.2.12
PANA-Termination-Answer PTA 7 <-------> 7.2.13
PANA-Error-Request PER 8 <-------> 7.2.14
PANA-Error-Answer PEA 8 <-------> 7.2.15
PANA-FirstAuth-End-Request PFER 9 <-------- 7.2.16
PANA-FirstAuth-End-Answer PFEA 9 --------> 7.2.17
PANA-Update-Request PUR 10 <-------> 7.2.18
PANA-Update-Answer PUA 10 <-------> 7.2.19
-----------------------------------------------------------
PANA-Auth-Request <-------> Figure 9: Table of PANA Messages
PANA-Auth-Answer <------->
PANA-Reauth-Request --------> 7.2 PANA Message ABNF Specification
PANA-Reauth-Answer <--------
PANA-FirstAuth-End-Request <-------- Every PANA message defined MUST include a corresponding ABNF
PANA-FirstAuth-End-Answer --------> [RFC2234] specification, which is used to define the AVPs that MUST
or MAY be present. The following format is used in the definition:
PANA-Bind-Request <-------- message-def = Message-Name "::=" PANA-message
PANA-Bind-Answer -------->
PANA-Ping-Request <-------> message-name = PANA-name
PANA-Ping-Answer <-------> PANA-name = ALPHA *(ALPHA / DIGIT / "-")
PANA-Termination-Request <-------> PANA-message = header [ *fixed] [ *required] [ *optional]
PANA-Termination-Answer <-------> [ *fixed]
PANA-Update-Request --------> header = "< PANA-Header: " Message-Id
PANA-Update-Answer <-------- [r-bit] [s-bit] [n-bit] ">"
PANA-Error-Request <-------> Message-Id = 1*DIGIT
PANA-Error-Answer <-------> ; The message code assigned to the message
Figure 10: PANA Message Overview r-bit = ", REQ"
; If present, the 'R' bit in the Message
; Flags is set, indicating that the message
; is a request, as opposed to an answer.
8.2 Message Specifications s-bit = ", SEP"
; If present, the 'S' bit in the Message
; Flags is set, indicating support for
; separate NAP and ISP authentication.
Every PANA message MUST include a corresponding ABNF [RFC2234] n-bit = ", NAP"
specification found in [RFC3588]. ; If present, the 'N' bit in the Message
; Flags is set, indicating that current
; EAP authentication is for NAP authentication.
Example: fixed = [qual] "<" avp-spec ">"
; Defines the fixed position of an AVP
message ::= < PANA-Header: <Message type>, [REQ] [SEP] > required = [qual] "{" avp-spec "}"
; The AVP MUST be present and can appear
; anywhere in the message.
optional = [qual] "[" avp-name "]"
; The avp-name in the 'optional' rule cannot
; evaluate to any AVP Name which is included
; in a fixed or required rule. The AVP can
; appear anywhere in the message.
qual = [min] "*" [max]
; See ABNF conventions, RFC 2234 Section 6.6.
; The absence of any qualifiers depends on whether
; it precedes a fixed, required, or optional
; rule. If a fixed or required rule has no
; qualifier, then exactly one such AVP MUST
; be present. If an optional rule has no
; qualifier, then 0 or 1 such AVP may be
; present.
;
; NOTE: "[" and "]" have a different meaning
; than in ABNF (see the optional rule, above).
; These braces cannot be used to express
; optional fixed rules (such as an optional
; MAC at the end). To do this, the convention
; is '0*1fixed'.
min = 1*DIGIT
; The minimum number of times the element may
; be present. The default value is zero.
max = 1*DIGIT
; The maximum number of times the element may
; be present. The default value is infinity. A
; value of zero implies the AVP MUST NOT be
; present.
avp-spec = PANA-name
; The avp-spec has to be an AVP Name, defined
; in the base or extended PANA protocol
; specifications.
avp-name = avp-spec / "AVP"
; The string "AVP" stands for *any* arbitrary
; AVP Name, which does not conflict with the
; required or fixed position AVPs defined in
; the message definition.
Example-Request ::= < "PANA-Header: 9999999, REQ >
< Session-Id >
{ Result-Code }
* [ AVP ] * [ AVP ]
0*1 < MAC >
8.2.1 PANA-PAA-Discover (PDI) 7.2.1 PANA-PAA-Discover (PDI)
The PANA-PAA-Discover (PDI) message is used to discover the address The PANA-PAA-Discover (PDI) message is used to discover the address
of PAA(s). Both sequence numbers in this message are set to zero of PAA(s). The sequence number in this message is always set to zero
(0). (0).
PANA-PAA-Discover ::= < PANA-Header: 1 > PANA-PAA-Discover ::= < PANA-Header: 1 >
[ Notification ]
* [ AVP ] * [ AVP ]
8.2.2 PANA-Start-Request (PSR) 7.2.2 PANA-Start-Request (PSR)
PANA-Start-Request (PSR) is sent by the PAA to the PaC. The PAA sets The PANA-Start-Request (PSR) message is sent by the PAA to the PaC to
the sequence number to an initial random value. advertise availability of the PAA and start PANA authentication. The
PAA sets the sequence number to an initial random value.
PANA-Start-Request ::= < PANA-Header: 2, REQ [SEP] > PANA-Start-Request ::= < PANA-Header: 2, REQ [, SEP] >
{ Nonce } { Nonce }
[ Cookie ] [ Cookie ]
[ EAP-Payload ] [ EAP-Payload ]
[ NAP-Information ] [ NAP-Information ]
* [ ISP-Information ] * [ ISP-Information ]
[ Protection-Capability] [ Protection-Capability]
[ PPAC ] [ PPAC ]
[ Notification ]
* [ AVP ] * [ AVP ]
8.2.3 PANA-Start-Answer (PSA) 7.2.3 PANA-Start-Answer (PSA)
PANA-Start-Answer (PSA) is sent by the PaC to the PAA in response to The PANA-Start-Answer (PSA) message is sent by the PaC to the PAA in
a PANA-Start-Request message. response to a PANA-Start-Request message. This message completes the
handshake to start PANA authentication.
PANA-Start-Answer ::= < PANA-Header: 2 [SEP] > PANA-Start-Answer ::= < PANA-Header: 2 [, SEP] >
{ Nonce } { Nonce }
[ Session-Id ]
[ Cookie ] [ Cookie ]
[ EAP-Payload ] [ EAP-Payload ]
[ ISP-Information ] [ ISP-Information ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC >
8.2.4 PANA-Auth-Request (PAR) 7.2.4 PANA-Auth-Request (PAR)
PANA-Auth-Request (PAR) is sent by the PAA to the PaC. The PANA-Auth-Request (PAR) message is either sent by the PAA or the
PaC. Its main task is to carry an EAP-Payload AVP.
PANA-Auth-Request ::= < PANA-Header: 3, REQ [SEP] [NAP] > PANA-Auth-Request ::= < PANA-Header: 3, REQ [, SEP] [, NAP] >
< Session-Id > < Session-Id >
< EAP-Payload > < EAP-Payload >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.5 PANA-Auth-Answer (PAN) 7.2.5 PANA-Auth-Answer (PAN)
PANA-Auth-Answer (PAN) is sent by the PaC to the PAA in response to a THe PANA-Auth-Answer (PAN) message is sent by either the PaC or the
PANA-Auth-Request message. PAA in response to a PANA-Auth-Request message. It MAY carry an
EAP-Payload AVP.
PANA-Auth-Answer ::= < PANA-Header: 3 [SEP] [NAP] > PANA-Auth-Answer ::= < PANA-Header: 3 [, SEP] [, NAP] >
< Session-Id > < Session-Id >
< EAP-Payload > [ EAP-Payload ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.6 PANA-Reauth-Request (PRAR) 7.2.6 PANA-Reauth-Request (PRAR)
PANA-Reauth-Request (PRAR) is sent by the PaC to the PAA. The PANA-Reauth-Request (PRAR) message is sent by the PaC to the PAA
to re-initiate EAP authentication.
PANA-Reauth-Request ::= < PANA-Header: 4, REQ > PANA-Reauth-Request ::= < PANA-Header: 4, REQ >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.7 PANA-Reauth-Answer (PRAA) 7.2.7 PANA-Reauth-Answer (PRAA)
PANA-Reauth-Answer (PRAA) is sent by the PAA to the PaC in response The PANA-Reauth-Answer (PRAA) message is sent by the PAA to the PaC
to a PANA-Reauth-Request message. in response to a PANA-Reauth-Request message.
PANA-Reauth-Answer ::= < PANA-Header: 4 > PANA-Reauth-Answer ::= < PANA-Header: 4 >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.8 PANA-Bind-Request (PBR) 7.2.8 PANA-Bind-Request (PBR)
PANA-Bind-Request (PBR) is sent by the PAA to the PaC. The PANA-Bind-Request (PBR) message is sent by the PAA to the PaC to
deliver the result of PANA authentication.
PANA-Bind-Request ::= < PANA-Header: 5, REQ [SEP] [NAP] > PANA-Bind-Request ::= < PANA-Header: 5, REQ [, SEP] [, NAP] >
< Session-Id > < Session-Id >
{ Result-Code } { Result-Code }
{ PPAC } { PPAC }
{ IP-Address } { IP-Address }
[ EAP-Payload ] [ EAP-Payload ]
[ Session-Lifetime ] [ Session-Lifetime ]
[ Protection-Capability ] [ Protection-Capability ]
[ Key-Id ] [ Key-Id ]
* [ Device-Id ] * [ Device-Id ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.9 PANA-Bind-Answer (PBA) 7.2.9 PANA-Bind-Answer (PBA)
PANA-Bind-Answer (PBA) is sent by the PaC to the PAA in response to a The PANA-Bind-Answer (PBA) message is sent by the PaC to the PAA in
PANA-Result-Request message. response to a PANA-Bind-Request message.
PANA-Bind-Answer ::= < PANA-Header: 5 [,SEP] [NAP] > PANA-Bind-Answer ::= < PANA-Header: 5 [,SEP] [, NAP] >
< Session-Id > < Session-Id >
{ Result-Code }
[ PPAC ] [ PPAC ]
[ Device-Id ] [ Device-Id ]
[ Key-Id ] [ Key-Id ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.10 PANA-Ping-Request (PPR) 7.2.10 PANA-Ping-Request (PPR)
PANA-Ping-Request (PPR) is either sent by the PaC or the PAA. The PANA-Ping-Request (PPR) message is either sent by the PaC or the
PAA for performing liveness test.
PANA-Ping-Request ::= < PANA-Header: 6, REQ > PANA-Ping-Request ::= < PANA-Header: 6, REQ >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.11 PANA-Ping-Answer (PPA) 7.2.11 PANA-Ping-Answer (PPA)
PANA-Ping-Answer (PPA) is sent in response to a PANA-Ping-Request. The PANA-Ping-Answer (PPA) message is sent in response to a
PANA-Ping-Request.
PANA-Ping-Answer ::= < PANA-Header: 6 > PANA-Ping-Answer ::= < PANA-Header: 6 >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.12 PANA-Termination-Request (PTR) 7.2.12 PANA-Termination-Request (PTR)
PANA-Termination-Request (PTR) is sent either by the PaC or the PAA. The PANA-Termination-Request (PTR) message is sent either by the PaC
or the PAA to terminate a PANA session.
PANA-Termination-Request ::= < PANA-Header: 7, REQ > PANA-Termination-Request ::= < PANA-Header: 7, REQ >
< Session-Id > < Session-Id >
< Termination-Cause > < Termination-Cause >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.13 PANA-Termination-Answer (PTA) 7.2.13 PANA-Termination-Answer (PTA)
PANA-Termination-Answer (PTA) is sent either by the PaC or the PAA in The PANA-Termination-Answer (PTA) message is sent either by the PaC
response to PANA-Termination-Request. or the PAA in response to PANA-Termination-Request.
PANA-Termination-Answer ::= < PANA-Header: 7 > PANA-Termination-Answer ::= < PANA-Header: 7 >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.14 PANA-Error-Request (PER) 7.2.14 PANA-Error-Request (PER)
PANA-Error is sent either by the PaC or the PAA. The PANA-Error-Request (PER) message is sent either by the PaC or the
PAA to report an error with the last received PANA message.
PANA-Error-Request ::= < PANA-Header: 8 REQ > PANA-Error-Request ::= < PANA-Header: 8, REQ >
< Session-Id > < Session-Id >
< Result-Code > < Result-Code >
{ Failed-AVP } * [ Failed-AVP ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.15 PANA-Error-Answer (PEA) 7.2.15 PANA-Error-Answer (PEA)
PANA-Error-Answer is sent in response to a PANA-Error-Request. The PANA-Error-Answer (PEA) message is sent in response to a
PANA-Error-Request.
PANA-Error-Answer ::= < PANA-Header: 8 > PANA-Error-Answer ::= < PANA-Header: 8 >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.16 PANA-FirstAuth-End-Request (PFER) 7.2.16 PANA-FirstAuth-End-Request (PFER)
PANA-FirstAuth-End-Request (PFER) is sent by the PAA to the PaC. The PANA-FirstAuth-End-Request (PFER) message is sent by the PAA to
the PaC to signal the result of the first EAP authentication method
when separate NAP and ISP authentication is performed.
PANA-FirstAuth-End-Request ::= < PANA-Header: 9, REQ [SEP] [NAP] > PANA-FirstAuth-End-Request ::= < PANA-Header: 9, REQ [, SEP] [, NAP] >
< Session-Id > < Session-Id >
{ EAP-Payload }
{ Result-Code } { Result-Code }
[ EAP-Payload ]
[ Key-Id ] [ Key-Id ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.17 PANA-FirstAuth-End-Answer (PFEA) 7.2.17 PANA-FirstAuth-End-Answer (PFEA)
PANA-FirstAuth-End-Answer (PFEA) is sent by the PaC to the PAA in The PANA-FirstAuth-End-Answer (PFEA) message is sent by the PaC to
response to a PANA-FirstAuth-End-Request message. the PAA in response to a PANA-FirstAuth-End-Request message.
PANA-FirstAuth-End-Answer ::= < PANA-Header: 9, REQ [SEP] [NAP] > PANA-FirstAuth-End-Answer ::= < PANA-Header: 9, REQ [, SEP] [, NAP] >
< Session-Id > < Session-Id >
[ Key-Id ] [ Key-Id ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.18 PANA-Update-Request (PUR) 7.2.18 PANA-Update-Request (PUR)
PANA-Update-Request (PUR) is sent by the PaC to the PAA. The PANA-Update-Request (PUR) message is sent either by the PaC or
the PAA to deliver attribute updates and notifications. In the scope
of this specification only the PaC IP address attribute can be
updated via this mechanism. An IP-Address AVP can only be included
in the PUR messages sent by the PaC. The PUR message can be used to
deliver just a notification as well.
PANA-Update-Request ::= < PANA-Header: 10, REQ > PANA-Update-Request ::= < PANA-Header: 10, REQ >
< Session-Id > < Session-Id >
< IP-Address > [ IP-Address ]
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.2.19 PANA-Update-Answer (PUA) 7.2.19 PANA-Update-Answer (PUA)
PANA-Update-Answer (PUA) is sent by the PAA to the PaC in response to The PANA-Update-Answer (PUA) message is sent by the PAA to the PaC in
a PANA-Update-Request. response to a PANA-Update-Request.
PANA-Update-Answer ::= < PANA-Header: 10 > PANA-Update-Answer ::= < PANA-Header: 10 >
< Session-Id > < Session-Id >
[ Notification ]
* [ AVP ] * [ AVP ]
0*1 < MAC > 0*1 < MAC >
8.3 AVPs in PANA 7.3 AVPs in PANA
PANA defines several AVPs that are specific to the protocol. A PANA defines several AVPs that are specific to the protocol. A
number of others AVPs are reused. These are specified in other number of others AVPs are reused. These are specified in other
documents such as [RFC3588]. documents such as [RFC3588].
The following tables lists the AVPs used in this document, and The following tables lists the AVPs used in this document, and
specifies in which PANA messages they MAY, or MAY NOT be present. specifies in which PANA messages they MAY, or MAY NOT be present.
The table uses the following symbols: The table uses the following symbols:
skipping to change at page 46, line 21 skipping to change at page 47, line 5
0-1 Zero or one instance of the AVP MAY be present in the message. 0-1 Zero or one instance of the AVP MAY be present in the message.
It is considered an error if there are more than one instance It is considered an error if there are more than one instance
of the AVP. of the AVP.
1 One instance of the AVP MUST be present in the message. 1 One instance of the AVP MUST be present in the message.
1+ At least one instance of the AVP MUST be present in the 1+ At least one instance of the AVP MUST be present in the
message. message.
+-----------------------------------------+ +---------------------------------------------+
| Message | | Message |
| Type | | Type |
+-----+-----+-----+-----+-----+-----+-----+ +---+---+---+---+---+----+----+---+---+---+---+
Attribute Name | PSR | PSA | PAR | PAN | PBR | PBA | PDI | Attribute Name |PDI|PSR|PSA|PAR|PAN|PRAR|PRAA|PBR|PBA|PPR|PPA|
--------------------+-----+-----+-----+-----+-----+-----+-----+ --------------------+---+---+---+---+---+----+----+---+---+---+---+
Result-Code | 0 | 0 | 0 | 0 | 1 | 1 | 0 | Cookie | 0 |0-1|0-1| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Session-Id | 0 | 0-1 | 1 | 1 | 1 | 1 | 0 | Device-Id | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0+|0-1| 0 | 0 |
Termination-Cause | 0 | 0 | 0 | 0 | 0 | 0 | 0 | EAP-Payload | 0 |0-1|0-1| 1 |0-1| 0 | 0 |0-1| 0 | 0 | 0 |
EAP-Payload | 0-1 | 0-1 | 1 | 0-1 | 0-1 | 0 | 0 | Failed-AVP | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
MAC | 0 | 0-1 | 0-1 | 0-1 | 0-1 | 0-1 | 0 | IP-Address | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
Nonce | 1 | 1 | 0 | 0 | 0 | 0 | 0 | ISP-Information | 0 | 0+|0-1| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Device-Id | 0 | 0 | 0 | 0 | 0+ | 0-1 | 0 | Key-Id | 0 | 0 | 0 | 0 | 0 | 0 | 0 |0-1|0-1| 0 | 0 |
Cookie | 0-1 | 0-1 | 0 | 0 | 0 | 0 | 0 | MAC | 0 | 0 | 0 |0-1|0-1|0-1 |0-1 |0-1|0-1|0-1|0-1|
Protection-Cap. | 0-1 | 0 | 0 | 0 | 0-1 | 0 | 0 | NAP-Information | 0 |0-1| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
PPAC | 0-1 | 0 | 0 | 0 | 1 | 0-1 | 0 | Nonce | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Session-Lifetime | 0 | 0 | 0 | 0 | 0-1 | 0 | 0 | Notification |0-1|0-1|0-1|0-1|0-1|0-1 |0-1 |0-1|0-1|0-1|0-1|
Failed-AVP | 0 | 0 | 0 | 0 | 0 | 0 | 0 | PPAC | 0 |0-1| 0 | 0 | 0 | 0 | 0 | 1 |0-1| 0 | 0 |
ISP-Information | 0+ | 0-1 | 0 | 0 | 0 | 0 | 0 | Protection-Cap. | 0 |0-1| 0 | 0 | 0 | 0 | 0 |0-1| 0 | 0 | 0 |
NAP-Information | 0-1 | 0 | 0 | 0 | 0 | 0 | 0 | Result-Code | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
Key-Id | 0 | 0 | 0 | 0 | 0-1 | 0-1 | 0 | Session-Id | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
IP-Address | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Session-Lifetime | 0 | 0 | 0 | 0 | 0 | 0 | 0 |0-1| 0 | 0 | 0 |
--------------------+-----+-----+-----+-----+-----+-----+-----+ Termination-Cause | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
--------------------+---+---+---+---+---+----+----+---+---+---+---+
Figure 11: AVP Occurrence Table (1/3) Figure 10: AVP Occurrence Table (1/2)
+-------------------------------------+ +---------------------------------+
| Message | | Message |
| Type | | Type |
+-----+-----+-----+-----+------+------+ +---+---+---+---+----+----+---+---+
Attribute Name | PPR | PPA | PTR | PTA | PFER | PFEA | Attribute Name |PTR|PTA|PER|PEA|PFER|PFEA|PUR|PUA|
--------------------+-----+-----+-----+-----+------+------+ --------------------+---+---+---+---+----+----+---+---+
Result-Code | 0 | 0 | 0 | 0 | 1 | 0 | Cookie | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Session-Id | 1 | 1 | 1 | 1 | 1 | 1 | Device-Id | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Termination-Cause | 0 | 0 | 1 | 0 | 0 | 0 | EAP-Payload | 0 | 0 | 0 | 0 |0-1 | 0 | 0 | 0 |
EAP-Payload | 0 | 0 | 0 | 0 | 1 | 0 | Failed-AVP | 0 | 0 | 0+| 0 | 0 | 0 | 0 | 0 |
MAC | 0-1 | 0-1 | 0-1 | 0-1 | 0-1 | 0-1 | IP-Address | 0 | 0 | 0 | 0 | 0 | 0 |0-1| 0 |
Nonce | 0 | 0 | 0 | 0 | 0 | 0 | ISP-Information | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Device-Id | 0 | 0 | 0 | 0 | 0 | 0 | Key-Id | 0 | 0 | 0 | 0 |0-1 |0-1 | 0 | 0 |
Cookie | 0 | 0 | 0 | 0 | 0 | 0 | MAC |0-1|0-1|0-1|0-1|0-1 |0-1 |0-1|0-1|
Protection-Cap. | 0 | 0 | 0 | 0 | 0 | 0 | NAP-Information | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
PPAC | 0 | 0 | 0 | 0 | 0 | 0 | Nonce | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Session-Lifetime | 0 | 0 | 0 | 0 | 0 | 0 | Notification |0-1|0-1|0-1|0-1|0-1 |0-1 |0-1|0-1|
Failed-AVP | 0 | 0 | 0 | 0 | 0 | 0 | PPAC | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
ISP-Information | 0 | 0 | 0 | 0 | 0 | 0 | Protection-Cap. | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
NAP-Information | 0 | 0 | 0 | 0 | 0 | 0 | Result-Code | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 |
Key-Id | 0 | 0 | 0 | 0 | 0-1 | 0-1 | Session-Id | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
IP-Address | 0 | 0 | 0 | 0 | 0 | 0 | Session-Lifetime | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
--------------------+-----+-----+-----+-----+------+------+ Termination-Cause | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
--------------------+---+---+---+---+----+----+---+---+
Figure 12: AVP Occurrence Table (2/3) Figure 11: AVP Occurrence Table (2/2)
+-------------------------------------+
| Message |
| Type |
+-----+-----+-----+-----+------+------+
Attribute Name | PUR | PUA | PER | PEA | PRAR | PRAA |
--------------------+-----+-----+-----+-----+------+------+
Result-Code | 0 | 0 | 1 | 0 | 0 | 0 |
Session-Id | 1 | 1 | 1 | 1 | 1 | 1 |
Termination-Cause | 0 | 0 | 0 | 0 | 0 | 0 |
EAP-Payload | 0 | 0 | 0 | 0 | 0 | 0 |
MAC | 0-1 | 0-1 | 0-1 | 0-1 | 0-1 | 0-1 |
Nonce | 0 | 0 | 0 | 0 | 0 | 0 |
Device-Id | 0 | 0 | 0 | 0 | 0 | 0 |
Cookie | 0 | 0 | 0 | 0 | 0 | 0 |
Protection-Cap. | 0 | 0 | 0 | 0 | 0 | 0 |
PPAC | 0 | 0 | 0 | 0 | 0 | 0 |
Session-Lifetime | 0 | 0 | 0 | 0 | 0 | 0 |
Failed-AVP | 0 | 0 | 1 | 0 | 0 | 0 |
ISP-Information | 0 | 0 | 0 | 0 | 0 | 0 |
NAP-Information | 0 | 0 | 0 | 0 | 0 | 0 |
Key-Id | 0 | 0 | 0 | 0 | 0 | 0 |
IP-Address | 1 | 0 | 0 | 0 | 0 | 0 |
--------------------+-----+-----+-----+-----+------+------+
Figure 13: AVP Occurrence Table (3/3) 7.3.1 Cookie AVP
8.3.1 MAC AVP The Cookie AVP (AVP Code 1) is used for carrying a random value
generated by the PAA. The AVP data is of type OctetString. The
random value is referred to as a cookie and used for making PAA
discovery robust against blind resource consumption DoS attacks. The
exact algorithms and syntax used by the PAA to generate a cookie does
not affect interoperability and not specified in this document. An
example cookie generation algorithm is shown in Section 4.2.
The first octet (8 bits) of the MAC (AVP Code 1) AVP data contains 7.3.2 Device-Id AVP
the MAC algorithm type. Rest of the AVP data payload contains the
MAC encoded in network byte order. The 8-bit Algorithm name space is The Device-Id AVP (AVP Code 2) is used for carrying device
managed by IANA [ianaweb]. The AVP length varies depending on the identifiers of PaC and EP(s). The AVP data is of Address type
used algorithm. [RFC3588]. IPv4 and IPv6 addresses are encoded as specified in
[RFC3588]. The content and format of data (including byte and bit
ordering) for link-layer addresses is expected to be specified in
specific documents that describe how IP operates over different
link-layers. For instance, [RFC2464]. Address families other than
that are defined for link-layer or IP addresses MUST NOT be used for
this AVP.
7.3.3 EAP-Payload AVP
The EAP-Payload AVP (AVP Code 3) is used for encapsulating the actual
EAP message that is being exchanged between the EAP peer and the EAP
authenticator. The AVP data is of type OctetString.
7.3.4 Failed-AVP AVP
The Failed-AVP AVP (AVP Code 4) provides debugging information in
cases where a request is rejected or not fully processed due to
erroneous information in a specific AVP. The AVP data is of type
Grouped. The format of the Failed-AVP AVP is defined in [RFC3588].
7.3.5 IP-Address AVP
The IP-Address AVP (AVP Code 5) contains an IP address of the PaC or
PAA. When it is sent by the PaC, it is used to convey the new IP
address of the PaC to the PAA when the PaC reconfigures its IP
address after the successful PANA authentication. This AVP is not
used if the PaC's IP address used during the authentication and
authorization phase is still valid. It is sent by the PAA in
PANA-Bind-Request to bind the IP address of the PAA to the PANA
session. The payload format of the IP-Address AVP is the same as
that of the Device-Id AVP (see See Section 7.3.2). Address families
for IPv4 or IPv6 MUST be used for this AVP.
7.3.6 ISP-Information AVP
The ISP-Information AVP (AVP Code 6) contains zero or one
Provider-Identifier AVP which carries the identifier of the ISP and
one Provider-Name AVP which carries the name of the ISP. The AVP
data is of type Grouped, and it has the following ABNF grammar:
ISP-Information ::= < AVP Header: 6 >
0*1 { Provider-Identifier }
{ Provider-Name }
* [ AVP ]
7.3.7 Key-Id AVP
The Key-Id AVP (AVP Code 7) is of type Integer32, and contains an
AAA-Key identifier. The AAA-Key identifier is assigned by PAA and
MUST be unique within the PANA session.
7.3.8 MAC AVP
The MAC (Message Authentication Code) AVP is used to integrity
protect PANA messages. The first octet of the this AVP (AVP Code 8)
data contains the MAC algorithm type. Rest of the AVP data payload
contains the MAC encoded in network byte order. The 8-bit Algorithm
name space is managed by IANA [ianaweb]. The AVP length varies
depending on the used algorithm.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Algorithm | MAC... | Algorithm | MAC...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Algorithm Algorithm
1 HMAC-SHA1 (20 bytes) 1 HMAC-SHA1 (20 bytes)
skipping to change at page 49, line 4 skipping to change at page 50, line 23
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Algorithm | MAC... | Algorithm | MAC...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Algorithm Algorithm
1 HMAC-SHA1 (20 bytes) 1 HMAC-SHA1 (20 bytes)
MAC MAC
The Message Authentication Code is encoded in network byte order. The Message Authentication Code is encoded in network byte order.
8.3.2 Device-Id AVP 7.3.9 NAP-Information AVP
The Device-Id AVP (AVP Code 2) is of Address type [RFC3588]. IPv4 The NAP-Information AVP (AVP Code 9) contains zero or one
and IPv6 addresses are encoded as specified in [RFC3588]. The Provider-Identifier AVP which carries the identifier of the NAP and
content and format of data (including byte and bit ordering) for one Provider-Name AVP which carries the name of the NAP. The AVP
link-layer addresses is expected to be specified in specific data is of type Grouped, and it has the following ABNF grammar:
documents that describe how IP operates over different link-layers.
For instance, [RFC2464]. Address families other than that are
defined for link-layer or IP addresses MUST NOT be used for this AVP.
8.3.3 Session-Id AVP NAP-Information ::= < AVP Header: 9 >
0*1 { Provider-Identifier }
{ Provider-Name }
* [ AVP ]
All messages pertaining to a specific PANA session MUST include a 7.3.10 Nonce AVP
Session-Id AVP (AVP Code 3) which carries a PAA-assigned fix value
throughout the lifetime of a session. When present, the Session-Id
SHOULD appear immediately following the PANA header.
The Session-Id MUST be globally and eternally unique, as it is meant The Nonce AVP (AVP Code 10) carries a randomly chosen value that is
to identify a PANA Session without reference to any other used in cryptographic key computations. The AVP data is of type
information, and may be needed to correlate historical authentication OctetString and it contains a randomly generated value in opaque
information with accounting information. The PANA Session-Id AVP has format. The data length MUST be between 8 and 256 bytes inclusive.
the same format as the Diameter Session-Id AVP [RFC3588].
8.3.4 Cookie AVP 7.3.11 Notification AVP
The Cookie AVP (AVP Code 4) is of type OctetString. The data is The Notification AVP (AVP Code 11) is optionally used to convey a
opaque and the exact content is outside the scope of this protocol. displayable message sent by either the PaC or the PAA. It can be
included in any message, whether it is a request or answer. In case
a notification needs to be sent but there is no outgoing PANA message
to deliver this AVP, a PANA-Update-Request that only carries a
Notification AVP SHOULD be generated.
8.3.5 Protection-Capability AVP Receipt this AVP does not change PANA state.
The Protection-Capability AVP (AVP Code 5) is of type Unsigned32. AVP data is of type OctetString and it contains UTF-8 encoded ISO
The AVP data indicates the cryptographic data protection capability 10646 characters [RFC2279]. The length of the displayable message is
supported by the EPs. Below is a list of specified data protection determined by the AVP Length field. The message MUST NOT be null
capabilities: terminated.
0 L2_PROTECTION 7.3.12 Post-PANA-Address-Configuration (PPAC) AVP
1 IPSEC_PROTECTION
8.3.6 Termination-Cause AVP The PPAC AVP (AVP Code 12) is used for conveying the available types
of post-PANA IP address configuration mechanisms when sent by the
PAA, and the chosen one when sent by the PaC. Each possible
mechanisms is represented by a flag. At least one or more of the
flags MUST be set when sent by the PAA, and exactly one flag MUST be
set when sent by the PaC. The AVP data is of type Unsigned32.
The Termination-Cause AVP (AVP Code 6) is of type of type Enumerated, The format of the AVP data is as follows:
and is used to indicate the reason why a session was terminated on
the access device. The AVP data is used as a collection of flags The
following Termination-Cause AVP defined in [RFC3588] are used for
PANA.
LOGOUT 1 (PaC -> PAA) 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|N|D|A|T|I| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The client initiated a disconnect PPAC Flags
ADMINISTRATIVE 4 (PAA -> PaC) N (No configuration)
The client was not granted access, or was disconnected, due to The PaC does not have to (if sent by PAA) or will not (if sent
administrative reasons, such as the receipt of a by PaC) configure a new IP address after PANA.
Abort-Session-Request message.
SESSION_TIMEOUT 8 (PAA -> PaC) D (DHCP)
The session has timed out, and service has been terminated. The PaC can (if sent by PAA) or will (if sent by PaC) use DHCP
[RFC2131][RFC3315] to configure a new IP address after PANA.
8.3.7 Result-Code AVP A (stateless autoconfiguration)
The Result-Code AVP (AVP Code 7) is of type Unsigned32 and indicates The PaC can/will use stateless IPv6 address autoconfiguration
[RFC2462] to configure a new IP address after PANA.
T (DHCP with IPsec tunnel mode)
The PaC can/will use [RFC3456] to configure a new IP address
after PANA.
I (IKEv2)
The PaC can/will use [I-D.ietf-ipsec-ikev2] to configure a new
IP address after PANA.
Reserved
These flag bits are reserved for future use, and MUST be set to
zero, and ignored by the receiver.
Unless the N-flag is set, the PaC MUST configure a new IP address
using one of the methods indicated by the other flags. Refer to
[I-D.ietf-pana-framework] for a detailed discussion on when these
methods can be used.
7.3.13 Protection-Capability AVP
The Protection-Capability AVP (AVP Code 13) indicates the
cryptographic data protection capability supported and required by
the EPs. The AVP data is of type Unsigned32. Below is a list of
valid data values and associated protection capabilities:
0 L2_PROTECTION
1 IPSEC_PROTECTION
7.3.14 Provider-Identifier AVP
The Provider-Identifier AVP (AVP Code 14) is of type Unsigned32, and
contains an IANA assigned "SMI Network Management Private Enterprise
Codes" [ianaweb] value, encoded in network byte order.
7.3.15 Provider-Name AVP
The Provider-Name AVP (AVP Code 15) is of type UTF8String, and
contains the UTF8-encoded name of the provider.
7.3.16 Result-Code AVP
The Result-Code AVP (AVP Code 16) is of type Unsigned32 and indicates
whether an EAP authentication was completed successfully or whether whether an EAP authentication was completed successfully or whether
an error occurred. Here are Result-Code AVP values taken from an error occurred. Here are Result-Code AVP values taken from
[RFC3588] and adapted for PANA. [RFC3588] and adapted for PANA.
8.3.7.1 Authentication Results Codes 7.3.16.1 Authentication Results Codes
These result code values inform the PaC about the authentication and These result code values inform the PaC about the authentication and
authorization result. The authentication result and authorization authorization result. The authentication result and authorization
result can be different as described below, but only one result that result can be different as described below, but only one result is
corresponds to the one detected first is returned. returned to the PaC. These codes are used with PANA-Bind-Request and
PANA-FirstAuth-End-Request messages.
PANA_SUCCESS 2001 PANA_SUCCESS 2001
Both the authentication and authorization processes are Both authentication and authorization processes are successful.
successful.
PANA_AUTHENTICATION_REJECTED 4001 PANA_AUTHENTICATION_REJECTED 4001
The authentication process failed. When this error is returned, Authentication has failed. When this error is returned, it is
the authorization process also fails. assumed that authorization is automatically failed.
PANA_AUTHORIZATION_REJECTED 5003 PANA_AUTHORIZATION_REJECTED 5003
The authorization process failed. This error could occur when The authorization process has failed. This error could occur when
authorization is rejected by a AAA proxy or rejected locally by a authorization is rejected by a AAA server or rejected locally by a
PAA, even if the authentication procedure succeeds. PAA, even if the authentication procedure has succeeded.
8.3.7.2 Protocol Error Result Codes 7.3.16.2 Protocol Error Result Codes
Protocol error result code values. These codes are used with PANA-Error-Request messages. Unless stated
otherwise, they can be generated by both the PaC and the PAA.
PANA_MESSAGE_UNSUPPORTED 3001 PANA_MESSAGE_UNSUPPORTED 3001
Error code from PAA to PaC or from PaC to PAA. Message type not Message type not recognized or supported.
recognized or supported.
PANA_UNABLE_TO_DELIVER 3002 PANA_UNABLE_TO_DELIVER 3002
Error code from PAA to PaC. PAA was unable to deliver the EAP The PAA was unable to deliver the EAP payload to the
payload to the authentication server. authentication server. Only the PAA can generate this code.
PANA_INVALID_HDR_BITS 3008 PANA_INVALID_HDR_BITS 3008
Error code from PAA to PaC or from PaC to PAA. A message was A message was received whose bits in the PANA header were either
received whose bits in the PANA header were either set to an set to an invalid combination, or to a value that is inconsistent
invalid combination, or to a value that is inconsistent with the with the message type definition.
message type's definition.
PANA_INVALID_AVP_BITS 3009
Error code from PAA to PaC or from PaC to PAA. A message was PANA_INVALID_AVP_FLAGS 3009
received that included an AVP whose flag bits are set to an A message was received that included an AVP whose flag bits are
unrecognized value, or that is inconsistent with the AVP's set to an unrecognized value, or that is inconsistent with the
definition. AVP's definition.
PANA_AVP_UNSUPPORTED 5001 PANA_AVP_UNSUPPORTED 5001
Error code from PAA to PaC or from PaC to PAA. The received The received message contained an AVP that is not recognized or
message contained an AVP that is not recognized or supported and supported and was marked with the Mandatory bit. A PANA message
was marked with the Mandatory bit. A PANA message with this error with this error MUST contain one or more Failed-AVP AVP containing
MUST contain one or more Failed-AVP AVP containing the AVPs that the AVPs that caused the failure.
caused the failure.
PANA_UNKNOWN_SESSION_ID 5002 PANA_UNKNOWN_SESSION_ID 5002
Error code from PAA to PaC or from PaC to PAA. The message The message contained an unknown Session-Id. A PANA message
contained an unknown Session-Id. PAA MUST NOT send this error indicating this error MUST include the unknown Session-Id AVP
result code value to PaC if PaC sent an unknown Session-Id in the
PANA-Start-Answer message (session resumption).
PANA_INVALID_AVP_VALUE 5004
Error code from PAA to PaC or from PaC to PAA. The message
contained an AVP with an invalid value in its data portion. A
PANA message indicating this error MUST include the offending AVPs
within a Failed-AVP AVP. within a Failed-AVP AVP.
PANA_INVALID_AVP_DATA 5004
The message contained an AVP with an invalid value in its data
portion. A PANA message indicating this error MUST include the
offending AVPs within a Failed-AVP AVP.
PANA_MISSING_AVP 5005 PANA_MISSING_AVP 5005
Error code from PAA to PaC or from PaC to PAA. The message did The message did not contain an AVP that is required by the message
not contain an AVP that is required by the message type type definition. If this value is sent in the Result-Code AVP, a
definition. If this value is sent in the Result-Code AVP, a
Failed-AVP AVP SHOULD be included in the message. The Failed-AVP Failed-AVP AVP SHOULD be included in the message. The Failed-AVP
AVP MUST contain an example of the missing AVP complete with the AVP MUST contain an example of the missing AVP complete with the
Vendor-Id if applicable. The value field of the missing AVP Vendor-Id if applicable. The value field of the missing AVP
should be of correct minimum length and contain zeroes. should be of correct minimum length and contain zeroes.
PANA_RESOURCES_EXCEEDED 5006 PANA_RESOURCES_EXCEEDED 5006
Error code from PAA to PaC. A message was received that cannot be A message was received that cannot be authorized because the
authorized because the client has already expended allowed client has already expended allowed resources. An example of this
resources. An example of this error condition is a client that is error condition is a client that is restricted to one PANA session
restricted to one PANA session and attempts to establish a second and attempts to establish a second session. Only the PAA can
session. generate this code.
PANA_CONTRADICTING_AVPS 5007 PANA_CONTRADICTING_AVPS 5007
Error code from PAA to PaC. The PAA has detected AVPs in the The PAA has detected AVPs in the message that contradicted each
message that contradicted each other, and is not willing to other, and is not willing to provide service to the client. One
provide service to the client. One or more Failed-AVP AVPs MUST or more Failed-AVP AVPs MUST be present, containing the AVPs that
be present, containing the AVPs that contradicted each other. contradicted each other. Only the PAA can generate this code.
PANA_AVP_NOT_ALLOWED 5008 PANA_AVP_NOT_ALLOWED 5008
Error code from PAA to PaC or from PaC to PAA. A message was A message was received with an AVP that MUST NOT be present. The
received with an AVP that MUST NOT be present. The Failed-AVP AVP Failed-AVP AVP MUST be included and contain a copy of the
MUST be included and contain a copy of the offending AVP. offending AVP.
PANA_AVP_OCCURS_TOO_MANY_TIMES 5009 PANA_AVP_OCCURS_TOO_MANY_TIMES 5009
Error code from PAA to PaC or from PaC to PAA. A message was A message was received that included an AVP that appeared more
received that included an AVP that appeared more often than often than permitted in the message definition. The Failed-AVP
permitted in the message definition. The Failed-AVP AVP MUST be AVP MUST be included and contain a copy of the first instance of
included and contain a copy of the first instance of the offending the offending AVP that exceeded the maximum number of occurrences.
AVP that exceeded the maximum number of occurrences.
PANA_UNSUPPORTED_VERSION 5011 PANA_UNSUPPORTED_VERSION 5011
Error code from PAA to PaC or from PaC to PAA. This error is
returned when a message was received, whose version number is This error is returned when a message was received, whose version
unsupported. number is unsupported.
PANA_UNABLE_TO_COMPLY 5012 PANA_UNABLE_TO_COMPLY 5012
This error is returned when a request is rejected for unspecified This error is returned when a request is rejected for unspecified
reasons. For example, when an EAP authentication fails at an EAP reasons. For example, when an EAP authentication fails at an EAP
pass-through authenticator without passing an EAP-Failure message pass-through authenticator without passing an EAP Failure message
to the PAA, a Result-Code AVP with this error code is carried in to the PAA, a Result-Code AVP with this error code is carried in
PANA-Error-Request message. the PANA-Error-Request message.
PANA_INVALID_AVP_LENGTH 5014 PANA_INVALID_AVP_LENGTH 5014
Error code from PAA to PaC or from PaC to PAA. The message The message contained an AVP with an invalid length. The
contained an AVP with an invalid length. The PANA-Error message PANA-Error-Request message indicating this error MUST include the
indicating this error MUST include the offending AVPs within a offending AVPs within a Failed-AVP AVP.
Failed-AVP AVP.
PANA_INVALID_MESSAGE_LENGTH 5015 PANA_INVALID_MESSAGE_LENGTH 5015
Error code from PAA to PaC or from PaC to PAA. This error is This error is returned when a message is received with an invalid
returned when a message is received with an invalid message message length.
length.
PANA_PROTECTION_CAPABILITY_UNSUPPORTED 5016 PANA_PROTECTION_CAPABILITY_UNSUPPORTED 5016
Error code from PaC to PAA. This error is returned when the PaC This error is returned when the PaC receives a PANA-Bind-Request
receives a PANA-Bind-Request with a Protection-Capability AVP and message with a Protection-Capability AVP and a valid MAC AVP but
a valid MAC AVP but does not support the protection capability does not support the protection capability specified in the
specified in the Protection-Capability AVP. Protection-Capability AVP. Only the PaC can generate this code.
PANA_PPAC_CAPABILITY_UNSUPPORTED 5017 PANA_PPAC_CAPABILITY_UNSUPPORTED 5017
This error is returned when there is no match between the list of
Error code from PaC to PAA. This error is returned in a PPAC methods offered by the PAA and the ones available on the PaC.
PANA-Bind-Answer message when there is no match between the list Only the PaC can generate this code.
of PPAC methods offered by the PAA and the ones available on the
PaC.
PANA_INVALID_IP_ADDRESS 5018 PANA_INVALID_IP_ADDRESS 5018
Error code from PAA to PaC. This error is returned in a This error is returned in a PANA-Error-Request message when the
PANA-Error-Request message when the IP-Address AVP in the received IP-Address AVP in the received PANA-Update-Request message is
PANA-Update-Request message is invalid (e.g., a non-unicast invalid (e.g., a non-unicast address). Only the PAA can generate
address). this code.
8.3.8 EAP-Payload AVP
The EAP-Payload AVP (AVP Code 8) is of type OctetString and is used
to encapsulate the actual EAP packet that is being exchanged between
the EAP peer and the EAP authenticator.
8.3.9 Session-Lifetime AVP
The Session-Lifetime AVP (AVP Code 9) data is of type Unsigned32. It
contains the number of seconds remaining before the current session
is considered expired.
8.3.10 Failed-AVP AVP
The Failed-AVP AVP (AVP Code 10) is of type Grouped and provides
debugging information in cases where a request is rejected or not
fully processed due to erroneous information in a specific AVP. The
format of the Failed-AVP AVP is defined in [RFC3588].
8.3.11 NAP-Information AVP
The NAP-Information AVP (AVP Code 11) is of type Grouped, and
contains zero or one Provider-Identifier AVP which carries the
identifier of the NAP and one Provider-Name AVP which carries the
name of the NAP. Its Data field has the following ABNF grammar:
NAP-Information ::= < AVP Header: 11 >
0*1 { Provider-Identifier }
{ Provider-Name }
* [ AVP ]
8.3.12 ISP-Information AVP
The ISP-Information AVP (AVP Code 12) is of type Grouped, and
contains zero or one Provider-Identifier AVP which carries the
identifier of the ISP and one Provider-Name AVP which carries the
name of the ISP. Its Data field has the following ABNF grammar:
ISP-Information ::= < AVP Header: 12 >
0*1 { Provider-Identifier }
{ Provider-Name }
* [ AVP ]
8.3.13 Provider-Identifier AVP
The Provider-Identifier AVP (AVP Code 13) is of type Unsigned32, and
contains an IANA assigned "SMI Network Management Private Enterprise
Codes" [ianaweb] value, encoded in network byte order.
8.3.14 Provider-Name AVP
The Provider-Name AVP (AVP Code 14) is of type UTF8String, and
contains the UTF8-encoded name of the provider.
8.3.15 Key-Id AVP
The Key-Id AVP (AVP Code 15) is of type Integer32, and contains an
AAA-Key identifier. The AAA-Key identifier is assigned by PAA and
MUST be unique within the PANA session.
8.3.16 Post-PANA-Address-Configuration (PPAC) AVP
The data field of PPAC AVP (AVP Code 16) is of type Unsigned32. The
AVP data is used to carry a set of flags which maps to various IP
address configuration methods. When sent by the PAA, the AVP MUST
have at least one of the flags set, and MAY have more than one set.
When sent by the PaC, only one of the flags MUST be set.
The format of the AVP data is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|N|D|A|T|I| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
PPAC Flags
N (No configuration)
The PaC does not have to (if sent by PAA) or will not (if sent
by PaC) configure a new IP address after PANA.
D (DHCP)
The PaC can (if sent by PAA) or will (if sent by PaC) use DHCP
[RFC2131][RFC3315] to configure a new IP address after PANA.
A (stateless autoconfiguration) 7.3.17 Session-Id AVP
The PaC can/will use stateless IPv6 address autoconfiguration All messages pertaining to a specific PANA session MUST include a
[RFC2462] to configure a new IP address after PANA. Session-Id AVP (AVP Code 17) which carries a PAA-assigned fixed
session identifier value throughout the lifetime of a session. When
present, the Session-Id AVP SHOULD appear immediately following the
PANA header.
T (DHCP with IPsec tunnel mode) The Session-Id MUST be globally and eternally unique, as it is meant
to identify a PANA session without reference to any other
information, and may be needed to correlate historical authentication
information with accounting information. The PANA Session-Id AVP has
the same format as the Diameter Session-Id AVP [RFC3588].
The PaC can/will use [RFC3456] to configure a new IP address 7.3.18 Session-Lifetime AVP
after PANA.
I (IKEv2) The Session-Lifetime AVP (AVP Code 18) contains the number of seconds
remaining before the current session is considered expired. The AVP
data is of type Unsigned32.
The PaC can/will use [I-D.ietf-ipsec-ikev2] to configure a new 7.3.19 Termination-Cause AVP
IP address after PANA.
Reserved The Termination-Cause AVP (AVP Code 19) is used for indicating the
reason why a session is terminated by the requester. The AVP data is
of type Enumerated. The following Termination-Cause data values are
used with PANA.
These flag bits are reserved for future use, and MUST be set to LOGOUT 1 (PaC -> PAA)
zero, and ignored by the receiver.
Unless the N-flag is set, the PaC MUST configure a new IP address The client initiated a disconnect
using one of the methods indicated by the other flags. Refer to
[I-D.ietf-pana-framework] for a detailed discussion on when these
methods can be used.
8.3.17 Nonce AVP ADMINISTRATIVE 4 (PAA -> PaC)
The Nonce AVP (AVP Code 17) is of type OctetString. The data The client was not granted access, or was disconnected, due to
contains a randomly generated value in opaque format. The data administrative reasons.
length MUST be between 8 and 256 bytes inclusive.
8.3.18 IP-Address AVP SESSION_TIMEOUT 8 (PAA -> PaC)
The IP-Address (AVP Code 18) contains an IP address of n a PaC or The session has timed out, and service has been terminated.
PAA. The payload format of the IP-Address AVP is the same as that of
the Device-Id AVP (see See Section 8.3.2). Address families for IPv4
or IPv6 MUST be used for this AVP. Address families for IPv4 or IPv6
MUST be used for this AVP.
9. PANA Protocol Message Retransmissions 8. Retransmission Timers
The PANA protocol provides retransmissions for the PANA-PAA-Discover The PANA protocol provides retransmissions for the PANA-PAA-Discover
and request messages. message and all request messages, with the exception that the
PANA-Start-Answer message is retransmitted instead of the
The rule is that the sender of the request message retransmits the PANA-Start-Request message in stateless PAA discovery.
request if the corresponding answer is not received in time. Answer
messages are sent as answers to the request messages, not based on a
timer.
PaC MUST retransmit PANA-PAA-Discover if a subsequent
PANA-Start-Request is not received in time. Even though a
PANA-Start-Request is received, PANA-PAA-Discover may still have to
be retransmitted. This is because a stateless PANA handshake
requires one time transmission of a PANA-Start-Request. PAA MUST NOT
start a timer and retransmit the request if it wants to avoid state
creation. If the received PANA-Start-Request included a Cookie AVP
(an indication of stateless handshake), PaC MUST retransmit
PANA-PAA-Discover until the first PANA-Auth-Request is received.
PANA retransmission timers are based on the model used in DHCPv6 PANA retransmission timers are based on the model used in DHCPv6
[RFC3315]. Variables used here are also borrowed from this [RFC3315]. Variables used here are also borrowed from this
specification. PANA is a request response like protocol. The specification. PANA is a request response like protocol. The
message exchange terminates when either the request sender message exchange terminates when either the request sender
successfully receives the appropriate answer, or when the message successfully receives the appropriate answer, or when the message
exchange is considered to have failed according to the retransmission exchange is considered to have failed according to the retransmission
mechanism described below. mechanism described below.
The retransmission behavior is controlled and described by the The retransmission behavior is controlled and described by the
skipping to change at page 58, line 46 skipping to change at page 59, line 32
once MRD seconds have elapsed since the client first transmitted the once MRD seconds have elapsed since the client first transmitted the
message. message.
If both MRC and MRD are non-zero, the message exchange fails whenever If both MRC and MRD are non-zero, the message exchange fails whenever
either of the conditions specified in the previous two paragraphs are either of the conditions specified in the previous two paragraphs are
met. met.
If both MRC and MRD are zero, the client continues to transmit the If both MRC and MRD are zero, the client continues to transmit the
message until it receives a response. message until it receives a response.
9.1 Transmission and Retransmission Parameters 8.1 Transmission and Retransmission Parameters
This section presents a table of values used to describe the message This section presents a table of values used to describe the message
retransmission behavior of PANA requests (REQ_*) and retransmission behavior of PANA requests and answers that are
PANA-PAA-Discover message (PDI_*). The table shows default values. retransmitted (REQ_*) and PANA-PAA-Discover message (PDI_*). The
table shows default values.
Parameter Default Description Parameter Default Description
------------------------------------------------ ------------------------------------------------
PDI_IRT 1 sec Initial PDI timeout. PDI_IRT 1 sec Initial PDI timeout.
PDI_MRT 120 secs Max PDI timeout value. PDI_MRT 120 secs Max PDI timeout value.
PDI_MRC 0 Configurable. PDI_MRC 0 Configurable.
PDI_MRD 0 Configurable. PDI_MRD 0 Configurable.
REQ_IRT 1 sec Initial Request timeout. REQ_IRT 1 sec Initial Request timeout.
REQ_MRT 30 secs Max Request timeout value. REQ_MRT 30 secs Max Request timeout value.
REQ_MRC 10 Max Request retry attempts. REQ_MRC 10 Max Request retry attempts.
REQ_MRD 0 Configurable. REQ_MRD 0 Configurable.
So for example the first RT for the PBR message is calculated using So for example the first RT for the PBR message is calculated using
REQ_IRT as the IRT: REQ_IRT as the IRT:
RT = REQ_IRT + RAND*REQ_IRT RT = REQ_IRT + RAND*REQ_IRT
10. IANA Considerations 9. IANA Considerations
This section provides guidance to the Internet Assigned Numbers This section provides guidance to the Internet Assigned Numbers
Authority (IANA) regarding registration of values related to the PANA Authority (IANA) regarding registration of values related to the PANA
protocol, in accordance with BCP 26 [IANA]. The following policies protocol, in accordance with BCP 26 [IANA]. The following policies
are used here with the meanings defined in BCP 26: "Private Use", are used here with the meanings defined in BCP 26: "Private Use",
"First Come First Served", "Expert Review", "Specification Required", "First Come First Served", "Expert Review", "Specification Required",
"IETF Consensus", "Standards Action". "IETF Consensus", "Standards Action".
This section explains the criteria to be used by the IANA for This section explains the criteria to be used by the IANA for
assignment of numbers within namespaces defined within this document. assignment of numbers within namespaces defined within this document.
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Required, the request is posted to the PANA WG mailing list (or, if Required, the request is posted to the PANA WG mailing list (or, if
it has been disbanded, a successor designated by the Area Director) it has been disbanded, a successor designated by the Area Director)
for comment and review, and MUST include a pointer to a public for comment and review, and MUST include a pointer to a public
specification. Before a period of 30 days has passed, the Designated specification. Before a period of 30 days has passed, the Designated
Expert will either approve or deny the registration request and Expert will either approve or deny the registration request and
publish a notice of the decision to the PANA WG mailing list or its publish a notice of the decision to the PANA WG mailing list or its
successor. A denial notice must be justified by an explanation and, successor. A denial notice must be justified by an explanation and,
in the cases where it is possible, concrete suggestions on how the in the cases where it is possible, concrete suggestions on how the
request can be modified so as to become acceptable. request can be modified so as to become acceptable.
10.1 PANA UDP Port Number 9.1 PANA UDP Port Number
PANA uses one well-known UDP port number (Section 5.2, Section 4.1 PANA uses one well-known UDP port number (Section 5.1, Section 4.2
and Section 7.1, which needs to be assigned by the IANA. and Section 6.1), which needs to be assigned by the IANA.
10.2 PANA Multicast Address 9.2 PANA Multicast Address
PANA uses one well-known IPv4 multicast address for which the scope PANA uses one well-known IPv4 multicast address for which the scope
is limited to be link-local by setting the TTL field to 255, and one is limited to be link-local by setting the TTL field to 255, and one
well-known IPv6 link-local scoped multicast address (Section 4.1 and well-known IPv6 link-local scoped multicast address (Section 4.2 and
Section 7.1), which need to be assigned by the IANA. Section 6.1), which need to be assigned by the IANA.
10.3 PANA Header 9.3 PANA Header
As defined in Section 7.2, the PANA header contains two fields that As defined in Section 6.2, the PANA header contains two fields that
requires IANA namespace management; the Message Type and Flags field. requires IANA namespace management; the Message Type and Flags field.
10.3.1 Message Type 9.3.1 Message Type
The Message Type namespace is used to identify PANA messages. Values The Message Type namespace is used to identify PANA messages. Values
0-65,533 are for permanent, standard message types, allocated by IETF 0-65,533 are for permanent, standard message types, allocated by IETF
Consensus [IANA]. This document defines the Message Types 1-10. See Consensus [IANA]. This document defines the Message Types 1-10. See
Section 8.2.1 through Section 8.2.19 for the assignment of the Section 7.2.1 through Section 7.2.19 for the assignment of the
namespace in this specification. namespace in this specification.
The values 65,534 and 65,535 (hexadecimal values 0xfffe - 0xffff) are The values 65,534 and 65,535 (hexadecimal values 0xfffe - 0xffff) are
reserved for experimental messages. As these codes are only for reserved for experimental messages. As these codes are only for
experimental and testing purposes, no guarantee is made for experimental and testing purposes, no guarantee is made for
interoperability between communicating PaC and PAA using experimental interoperability between the communicating PaC and PAA using
commands, as outlined in [IANA-EXP]. experimental commands, as outlined in [IANA-EXP].
10.3.2 Flags 9.3.2 Flags
There are 16 bits in the Flags field of the PANA header. This There are 16 bits in the Flags field of the PANA header. This
document assigns bit 0 ('R'equest), bit 1 ('S'eparate) and bit 2 document assigns bit 0 ('R'equest), bit 1 ('S'eparate) and bit 2
('N'AP Authentication). The remaining bits MUST only be assigned via ('N'AP Authentication). The remaining bits MUST only be assigned via
a Standards Action [IANA]. a Standards Action [IANA].
10.4 AVP Header 9.4 AVP Header
As defined in Section 7.3, the AVP header contains three fields that As defined in Section 6.3, the AVP header contains three fields that
requires IANA namespace management; the AVP Code, AVP Flags and requires IANA namespace management; the AVP Code, AVP Flags and
Vendor-Id fields where only the AVP Code and AVP Flags create new Vendor-Id fields where only the AVP Code and AVP Flags create new
namespaces. namespaces.
10.4.1 AVP Code 9.4.1 AVP Code
The AVP Code namespace is used to identify attributes. There are The AVP Code namespace is used to identify attributes. There are
multiple namespaces. Vendors can have their own AVP Codes namespace multiple namespaces. Vendors can have their own AVP Codes namespace
which will be identified by their Vendor-ID (also known as which will be identified by their Vendor-ID (also known as
Enterprise-Number) and they control the assignments of their Enterprise-Number) and they control the assignments of their
vendor-specific AVP codes within their own namespace. The absence of vendor-specific AVP codes within their own namespace. The absence of
a Vendor-ID or a Vendor-ID value of zero (0) identifies the IETF IANA a Vendor-ID or a Vendor-ID value of zero (0) identifies the IETF IANA
controlled AVP Codes namespace. The AVP Codes and sometimes also controlled AVP Codes namespace. The AVP Codes and sometimes also
possible values in an AVP are controlled and maintained by IANA. possible values in an AVP are controlled and maintained by IANA.
AVP Code 0 is not used. This document defines the AVP Codes 1-18. AVP Code 0 is not used. This document defines the AVP Codes 1-19.
See Section 8.3.1 through Section 8.3.18 for the assignment of the See Section 7.3.8 through Section 7.3.5 for the assignment of the
namespace in this specification. namespace in this specification.
AVPs may be allocated following Designated Expert with Specification AVPs may be allocated following Designated Expert with Specification
Required [IANA]. Release of blocks of AVPs (more than 3 at a time Required [IANA]. Release of blocks of AVPs (more than 3 at a time
for a given purpose) should require IETF Consensus. for a given purpose) should require IETF Consensus.
Note that PANA defines a mechanism for Vendor-Specific AVPs, where Note that PANA defines a mechanism for Vendor-Specific AVPs, where
the Vendor-Id field in the AVP header is set to a non-zero value. the Vendor-Id field in the AVP header is set to a non-zero value.
Vendor-Specific AVPs codes are for Private Use and should be Vendor-Specific AVPs codes are for Private Use and should be
encouraged instead of allocation of global attribute types, for encouraged instead of allocation of global attribute types, for
functions specific only to one vendor's implementation of PANA, where functions specific only to one vendor's implementation of PANA, where
no interoperability is deemed useful. Where a Vendor-Specific AVP is no interoperability is deemed useful. Where a Vendor-Specific AVP is
implemented by more than one vendor, allocation of global AVPs should implemented by more than one vendor, allocation of global AVPs should
be encouraged instead. be encouraged instead.
10.4.2 Flags 9.4.2 Flags
There are 16 bits in the AVP Flags field of the AVP header, defined There are 16 bits in the AVP Flags field of the AVP header, defined
in Section 7.3. This document assigns bit 0 ('V'endor Specific) and in Section 6.3. This document assigns bit 0 ('V'endor Specific) and
bit 1 ('M'andatory). The remaining bits should only be assigned via bit 1 ('M'andatory). The remaining bits should only be assigned via
a Standards Action . a Standards Action .
10.5 AVP Values 9.5 AVP Values
Certain AVPs in PANA define a list of values with various meanings. Certain AVPs in PANA define a list of values with various meanings.
For attributes other than those specified in this section, adding For attributes other than those specified in this section, adding
additional values to the list can be done on a First Come, First additional values to the list can be done on a First Come, First
Served basis by IANA [IANA]. Served basis by IANA [IANA].
10.5.1 Algorithm Values of MAC AVP 9.5.1 Algorithm Values of MAC AVP
As defined in Section 8.3.1, the Algorithm field of MAC AVP (AVP Code As defined in Section 7.3.8, the Algorithm field of MAC AVP (AVP Code
1) defines the value of 1 (one) for HMAC-SHA1. 8) defines the value of 1 (one) for HMAC-SHA1.
All remaining values are available for assignment via IETF Consensus All remaining values are available for assignment via IETF Consensus
[IANA]. [IANA].
10.5.2 Protection-Capability AVP Values 9.5.2 Post-PANA-Address-Configuration AVP Values
As defined in Section 8.3.5, the Protection-Capability AVP (AVP Code As defined in Section 7.3.12, the Post-PANA-Address-Configuration AVP
5) defines the values 0 and 1. (AVP Code 12) defines the bits 0 ('N': no configuration), 1 ('D':
DHCP), 2 ('A' stateless autoconfiguration), 3 ('T': DHCP with IPsec
tunnel mode) and 4 ('I': IKEv2).
All remaining values are available for assignment via a Standards All remaining values are available for assignment via a Standards
Action [IANA]. Action [IANA].
10.5.3 Termination-Cause AVP Values 9.5.3 Protection-Capability AVP Values
As defined in Section 8.3.6, the Termination-Cause AVP (AVP Code 6) As defined in Section 7.3.13, the Protection-Capability AVP (AVP Code
defines the values 1, 4 and 8. 13) defines the values 0 and 1.
All remaining values are available for assignment via IETF Consensus All remaining values are available for assignment via a Standards
[IANA]. Action [IANA].
10.5.4 Result-Code AVP Values 9.5.4 Result-Code AVP Values
As defined in Section 8.3.7.1 and Section 8.3.7.2 the Result-Code AVP As defined in Section 7.3.16.1 and Section 7.3.16.2 the Result-Code
(AVP Code 7) defines the values 2001, 3001-3002, 3008-3009, 4001, AVP (AVP Code 16) defines the values 2001, 3001-3002, 3008-3009,
5001-5009 and 5011-5019. 4001, 5001-5009 and 5011-5019.
All remaining values are available for assignment via IETF Consensus All remaining values are available for assignment via IETF Consensus
[IANA]. [IANA].
10.5.5 Post-PANA-Address-Configuration AVP Values 9.5.5 Termination-Cause AVP Values
As defined in Section 8.3.16, the Post-PANA-Address-Configuration AVP As defined in Section 7.3.19, the Termination-Cause AVP (AVP Code 19)
(AVP Code 17) defines the bits 0 ('N': no configuration), 1 ('D': defines the values 1, 4 and 8.
DHCP), 2 ('A' stateless autoconfiguration), 3 ('T': DHCP with IPsec
tunnel mode) and 4 ('I': IKEv2).
All remaining values are available for assignment via a Standards All remaining values are available for assignment via IETF Consensus
Action [IANA]. [IANA].
11. Security Considerations 10. Security Considerations
The PANA protocol defines a UDP-based EAP encapsulation that runs The PANA protocol defines a UDP-based EAP encapsulation that runs
between two IP-enabled nodes on the same IP link. Various security between two IP-enabled nodes on the same IP link. Various security
threats that are relevant to a protocol of this nature are outlined threats that are relevant to a protocol of this nature are outlined
in [I-D.ietf-pana-threats-eval]. Security considerations stemming in [I-D.ietf-pana-threats-eval]. Security considerations stemming
from the use of EAP and EAP methods are discussed in [RFC3748]. This from the use of EAP and EAP methods are discussed in [RFC3748]. This
section provides a discussion on the security-related issues that are section provides a discussion on the security-related issues that are
related to PANA framework and protocol design. related to PANA framework and protocol design.
An important element in assessing security of PANA design and An important element in assessing security of PANA design and
deployment in a network is the presence of lower-layer (physical and deployment in a network is the presence of lower-layer (physical and
link-layer) security. In the context of this document, lower-layers link-layer) security. In the context of this document, lower-layers
are said to be secure if they can prevent eavesdropping and spoofing are said to be secure if they can prevent eavesdropping and spoofing
of packets. Examples of such networks are physically-secured DSL of packets. Examples of such networks are physically-secured DSL
networks and 3GPP2 networks with crytographically-secured cdma2000 networks and 3GPP2 networks with crytographically-secured cdma2000
link-layer. link-layer. In these examples, the lower-layer security is enabled
even before running the first PANA-based authentication. In the
In these examples, the lower-layer security is enabled even before absence of such a pre-established secure channel, one needs to be
running the first PANA-based authentication. In the absence of such created in conjunction with PANA using a link-layer or network-layer
a pre-established secure channel, one needs to be created in
conjunction with PANA using a link-layer or network-layer
cryptographic mechanism (e.g., IPsec). cryptographic mechanism (e.g., IPsec).
11.1 General Security Measures 10.1 General Security Measures
PANA provides multiple mechanisms to secure a PANA session. PANA provides multiple mechanisms to secure a PANA session.
Since PaC and PAA are on the same IP link, a simple TTL check on the Since the PaC and PAA are on the same IP link, a simple TTL check on
received PANA messages prevents off-link attacks. the received PANA messages prevents off-link attacks.
PANA messages carry sequence numbers, which are monotonically PANA messages carry sequence numbers, which are monotonically
incremented by 1 with every new request message. These numbers are incremented by 1 with every new request message. These numbers are
randomly initialized at the beginning of the session, and verified randomly initialized at the beginning of the session, and verified
against expected numbers upon receipt. A message whose sequence against expected numbers upon receipt. A message whose sequence
number is different than the expected one is silently discarded. In number is different than the expected one is silently discarded. In
addition to accomplishing orderly delivery of EAP messages and addition to accomplishing orderly delivery of EAP messages and
duplicate elimination, this scheme also helps prevent an adversary duplicate elimination, this scheme also helps prevent an adversary
spoof messages to disturb ongoing PANA and EAP sessions unless it can spoof messages to disturb ongoing PANA and EAP sessions unless it can
also eavesdrop to synchronize on the expected sequence number. also eavesdrop to synchronize on the expected sequence number.
Furthermore, impact of replay attacks is reduced as any stale message
(i.e., a request or answer with an unexpected sequence number) and
any duplicate answer are immediately discarded, and a duplicate
request can trigger transmission of the cached answer (i.e., no need
to process the request and generate a new answer).
The PANA framework defines EP which is ideally located on a network The PANA framework defines EP which is ideally located on a network
device that can filter traffic from the PaCs before the traffic device that can filter traffic from the PaCs before the traffic
enters the Internet. A set of filters can be used to discard enters the Internet/intranet. A set of filters can be used to
unauthorized packets, such as a PANA-Start-Request message that is discard unauthorized packets, such as a PANA-Start-Request message
received from the segment of the access network where only PaCs are that is received from the segment of the access network where only
supposed to be connected. the PaCs are supposed to be connected.
The protocol also provides authentication and integrity protection to The protocol also provides authentication and integrity protection to
PANA messages when the used EAP method can generate cryptographic PANA messages when the used EAP method can generate cryptographic
session keys. A PANA SA is generated based on the AAA-Key exported session keys. A PANA SA is generated based on the AAA-Key exported
by the EAP method. This SA is used for generating per-packet MAC to by the EAP method. This SA is used for generating per-packet MAC to
protect the PANA header and payload (including the complete EAP protect the PANA header and payload (including the complete EAP
message). message).
The cryptographic protection prevents an adversary from acting as a The cryptographic protection prevents an adversary from acting as a
man-in-the-middle, injecting messages, replaying messages and man-in-the-middle, injecting messages, replaying messages and
modifying the content of the exchanged messages. Any packet that modifying the content of the exchanged messages. Any packet that
fails to pass the MAC verification is silently discarded. The fails to pass the MAC verification is silently discarded. The
earliest this protection can be enabled is when the very first earliest this protection can be enabled is when the very first
PANA-Bind-Request that signals a successful authentication is PANA-Bind-Request or PANA-FirstAuth-End-Request message that signals
generated. Starting with the PANA-Bind-Request and PANA-Bind-Answer, a successful authentication is generated. Starting with these
any subsequent PANA message until the session gets torn down can be messages, any subsequent PANA message until the session gets torn
cryptographically protected. down can be cryptographically protected.
The PANA SA enables authenticated and integrity protected exchange of The PANA SA enables authenticated and integrity protected exchange of
the device ID information between the PaC and PAA. This ensures the device ID information between the PaC and PAA. This ensures
there were no man-in-the-middle during the PANA authentication. there were no man-in-the-middle during the PANA authentication.
The lifetime of the PANA SA is bounded by the AAA-authorized session The lifetime of the PANA SA is set to PANA session lifetime which is
lifetime with an additional tolerance period. Unless PANA state is bounded by the lifetime granted by the authentication server. An
updated by executing another EAP authentication, the PANA SA is implementation MAY add a tolerance period to that value. Unless the
removed when the current session expires. PANA session is extended by executing another EAP authentication, the
PANA SA is removed when the current session expires.
The ability to use cryptographic protection within PANA is determined The ability to use cryptographic protection within PANA is determined
by the used EAP method, which is generally dictated by the deployment by the used EAP method, which is generally dictated by the deployment
environment. Insecure lower-layers necessitate use of key-generating environment. Insecure lower-layers necessitate use of key-generating
EAP methods. In networks where lower-layers are already secured, EAP methods. In networks where lower-layers are already secured,
cryptographic protection of PANA messages is not necessary. cryptographic protection of PANA messages is not necessary.
11.2 Discovery 10.2 Discovery
The discovery and handshake phase is vulnerable to spoofing attacks The discovery and handshake phase is vulnerable to spoofing attacks
as these messages are not authenticated and integrity protected. In as these messages are not authenticated and integrity protected. In
order to prevent very basic denial-of service attacks an adversary order to prevent very basic denial-of service attacks an adversary
should not be able to cause state creation by sending discovery should not be able to cause state creation by sending discovery
messages to the PAA. This protection is achieved by using a messages to the PAA. This protection is achieved by using a
cookie-based scheme (similar to [RFC2522] which allows the responder cookie-based scheme (similar to [RFC2522] which allows the responder
(PAA) to be stateless in the first round of message exchange. A (PAA) to be stateless in the first round of message exchange. A
return-routability test does not provide additional protection as return-routability test does not provide additional protection as
PANA traffic is not routed but simply forwarded on-link. It is PANA traffic is not routed but simply forwarded on-link. It is
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In networks where lower-layers are not secured prior to running PANA, In networks where lower-layers are not secured prior to running PANA,
the capability discovery enabled through inclusion of the capability discovery enabled through inclusion of
Protection-Capability and Post-PANA-Address-Configuration AVPs in a Protection-Capability and Post-PANA-Address-Configuration AVPs in a
PANA-Start-Request message is susceptible to spoofing leading to PANA-Start-Request message is susceptible to spoofing leading to
denial-of service attacks. Therefore, usage of these AVPs during the denial-of service attacks. Therefore, usage of these AVPs during the
discovery and handshake phase in such insecure networks is NOT discovery and handshake phase in such insecure networks is NOT
RECOMMENDED. The same AVPs are delivered via an integrity-protected RECOMMENDED. The same AVPs are delivered via an integrity-protected
PANA-Bind-Request upon successful authentication. PANA-Bind-Request upon successful authentication.
11.3 EAP Methods 10.3 EAP Methods
Eavesdropping EAP packets might cause problems when the EAP method is Eavesdropping EAP messages might cause problems when the EAP method
weak and enables dictionary or replay attacks or even allows an is weak and enables dictionary or replay attacks or even allows an
adversary to learn the long-term password directly. Furthermore, if adversary to learn the long-term password directly. Furthermore, if
the optional EAP Identity payload is used then it allows the the optional EAP Response/Identity payload is used then it allows the
adversary to learn the identity of the PaC. In such a case a privacy adversary to learn the identity of the PaC. In such a case a privacy
problem is prevalent. problem is prevalent.
To prevent these threats, [I-D.ietf-pana-framework] suggests using To prevent these threats, [I-D.ietf-pana-framework] suggests using
proper EAP methods for particular environments. Depending on the proper EAP methods for particular environments. Depending on the
deployment environment an EAP authentication which supports user deployment environment an EAP authentication method which supports
identity confidentiality, protection against dictionary attacks and user identity confidentiality, protection against dictionary attacks
session key establishment must be used. It is therefore the and session key establishment must be used. It is therefore the
responsibility of the network operators and users to choose a proper responsibility of the network operators and users to choose a proper
EAP method. EAP method.
11.4 Separate NAP and ISP Authentication 10.4 Separate NAP and ISP Authentication
The PANA design allows running two separate EAP sessions for the same The PANA design allows running two separate EAP sessions for the same
PaC in a single authentication phase: one with the NAP, and one with PaC in the authentication and authorization phase: one with the NAP,
the ISP. The process of arriving at the resultant authorization, and one with the ISP. The process of arriving at the resultant
which is a combination of the individual authorizations obtained from authorization, which is a combination of the individual
respective service providers, is outside the scope of this protocol. authorizations obtained from respective service providers, is outside
In the absence of lower-layer security, both authentications MUST be the scope of this protocol. In the absence of lower-layer security,
able to generate a AAA-Key, leading to generation of a PANA SA. The both authentications MUST be able to generate a AAA-Key, leading to
resultant PANA SA cryptographically binds the two AAA-Keys together, generation of a PANA SA. The resultant PANA SA cryptographically
hence it prevents man-in-the-middle attacks. binds the two AAA-Keys together, hence it prevents man-in-the-middle
attacks.
11.5 Cryptographic Keys 10.5 Cryptographic Keys
When the EAP method exports a AAA-Key, this key is used to produce a When the EAP method exports a AAA-Key, this key is used to produce a
PANA SA with PANA_MAC_KEY with a distinct key ID. The PANA_MAC_KEY PANA SA with PANA_MAC_KEY with a distinct key ID. The PANA_MAC_KEY
is unique to the PANA session, and takes PANA-based nonce values into is unique to the PANA session, and takes PANA-based nonce values into
computation to cryptographically separate itself from the AAA-Key. computation to cryptographically separate itself from the AAA-Key.
The PANA_MAC_KEY is solely used for authentication and integrity The PANA_MAC_KEY is solely used for authentication and integrity
protection of the PANA messages within the designated session. protection of the PANA messages within the designated session.
Two AAA-Keys may be generated as a result of separate NAP and ISP Two AAA-Keys may be generated as a result of separate NAP and ISP
authentication. In that case, the AAA-Key used with the PANA SA is authentication. In that case, the AAA-Key used with the PANA SA is
the combination of both keys. the combination of both keys.
The PANA SA lifetime is bounded by the AAA-Key lifetime. Another The PANA SA lifetime is bounded by the AAA-Key lifetime. Another
execution of EAP method yields in a new AAA-Key, and updates the PANA execution of EAP method yields in a new AAA-Key, and updates the PANA
SA, PANA_MAC_KEY and key ID. SA, PANA_MAC_KEY and key ID.
Upon PaC's movement to a another PAA (new PAA) and request to perform
a context transfer based optimization, the current PAA computes a
AAA-Key-int based on the AAA-Key, ID of new PAA, and the session ID.
This AAA-Key-int is delivered to the new PAA, and used in the
computation of AAA-Key-new, which further takes a pair of nonce
values into account. After this point on, the AAA-Key-new becomes
the AAA-Key between the PaC and the new PAA.
When link-layer or network-layer ciphering [I-D.ietf-pana-ipsec] is When link-layer or network-layer ciphering [I-D.ietf-pana-ipsec] is
enabled as a result of successful PANA authentication, a separate enabled as a result of successful PANA authentication, a separate
master key is generated based on the AAA-Key, session ID, key ID, and PaC-EP master key is generated based on the AAA-Key, session
EP ID. identifier, key identifier, and EP device identifier.
The lifetime of this key is bounded by the lifetime of the PANA SA. The lifetime of PaC-EP master key is bounded by the lifetime of the
This key may be used with a secure association protocol PANA SA. This key may be used with a secure association protocol
[I-D.ietf-ipsec-ikev2] to produce further cipher-specific and [I-D.ietf-ipsec-ikev2] to produce further cipher-specific and
transient keys. transient keys.
11.6 Per-packet Ciphering 10.6 Per-packet Ciphering
Networks that are not secured at the lower-layers prior to running Networks that are not secured at the lower-layers prior to running
PANA can rely on enabling per-packet data traffic ciphering upon PANA can rely on enabling per-packet data traffic ciphering upon
successful PANA session establishment. The PANA framework allows successful PANA session establishment. The PANA framework allows
generation of a master key from AAA-Key for using with a per-packet generation of a PaC-EP master key from AAA-Key for using with a
protection mechanism, such as link-layer or IPsec-based ciphering per-packet protection mechanism, such as link-layer or IPsec-based
[I-D.ietf-pana-ipsec]. In case the master key is not readily useful ciphering [I-D.ietf-pana-ipsec]. In case the master key is not
to the ciphering mechanism, an additional secure association protocol readily useful to the ciphering mechanism, an additional secure
[I-D.ietf-ipsec-ikev2] may be needed to produce the required keying association protocol [I-D.ietf-ipsec-ikev2] may be needed to produce
material. These mechanisms ultimately establish a cryptographic the required keying material. These mechanisms ultimately establish
binding between the data traffic generated by and for a client and a cryptographic binding between the data traffic generated by and for
the authenticated identity of the client. Data traffic must be a client and the authenticated identity of the client. Data traffic
minimally data origin authenticated, replay and integrity protected, must be minimally data origin authenticated, replay and integrity
and optionally encrypted. protected, and optionally encrypted.
11.7 PAA-to-EP Communication 10.7 PAA-to-EP Communication
The PANA framework allows separation of PAA from EP(s). SNMPv3 The PANA framework allows separation of PAA from EP(s). SNMPv3
[I-D.ietf-pana-snmp] is used between the the PAA and EP for [I-D.ietf-pana-snmp] is used between the PAA and EP for provisioning
provisioning authorized PaC information on the EP. This exchange authorized PaC information on the EP. This exchange MUST be always
MUST be always physically or cryptographically protected for physically or cryptographically protected for authentication,
authentication, integrity and replay protection. It MUST also be integrity and replay protection. It MUST also be privacy-protected
privacy-protected when per-PaC master key for per-packet ciphering is when PaC-EP master key for per-packet ciphering is transmitted to the
transmitted to the EP. EP.
The per-packet ciphering master key MUST be unique to the PaC and EP The PaC-EP master key MUST be unique to the PaC and EP pair. The
pair. The session ID and EP's device ID are taken into computation session identifier and the device identifier of the EP are taken into
for achieving this effect [I-D.ietf-pana-ipsec]. Compromise of an EP computation for achieving this effect [I-D.ietf-pana-ipsec].
does not automatically lead to compromise of another EP or the PAA. Compromise of an EP does not automatically lead to compromise of
another EP or the PAA.
11.8 Livenes Test 10.8 Liveness Test
A PANA session is associated with a session lifetime. The session is A PANA session is associated with a session lifetime. The session is
terminated unless it is refreshed by a new round of EAP terminated unless it is refreshed by a new round of EAP
authentication before it expires. Therefore, at the latest a authentication before it expires. Therefore, at the latest a
disconnected client can be detected when its lifetime expires. A disconnected client can be detected when its session expires. A
disconnect may also be detected earlier by using PANA ping messages. disconnect may also be detected earlier by using PANA ping messages.
A request message can be generated by either PaC or PAA at any time A request message can be generated by either PaC or PAA at any time
and the peer must respond with an answer message. A successful and the peer must respond with an answer message. A successful
round-trip of this exchange is a simple verification that the peer is round-trip of this exchange is a simple verification that the peer is
alive. This test can be engaged when there is a possibility that the alive.
peer might have disconnected (e.g., after discontinuation of data
traffic). Periodic use of this exchange as a keep-alive requires
additional care as it might result in congestion and hence false
alarms. This exchange is cryptographically protected when a PANA SA
is available in order to prevent threats associated with the abuse of
this functionality.
11.9 Mobility Optimization This test can be engaged when there is a possibility that the peer
might have disconnected (e.g., after the discontinuation of data
traffic for an extended period of time). Periodic use of this
exchange as a keep-alive requires additional care as it might result
in congestion and hence false alarms.
The mobility optimization described in Section 4.12 involves the This exchange is cryptographically protected when a PANA SA is
previous PAA providing a AAA-Key to the current PAA of the PaC. available in order to prevent threats associated with the abuse of
There are security risks stemming from potential compromise of PAAs. this functionality.
Compromise of the current PAA does not yield compromise of the
previous PAA, as AAA-Key cannot be computed from a compromised
AAA-Key-new. But a compromised previous PAA along with the
intercepted nonce values on the current link leads to the compromise
of AAA-Key-new. Operators should be aware of the potential risk of
using this optimization. An operator can reduce the risk exposure by
forcing the PaC to perform an EAP-based authentication immediately
after the PaC gains access to new link via the optimized PANA
execution.
11.10 Updating PaC's IP Address Any valid PANA answer message received in response to a recently sent
request message can be taken as an indication of peer's liveness.
The PaC or PAA MAY forgo sending an explicit PANA-Ping-Request if a
recent exchange has already confirmed that the peer is alive.
10.9 Updating PaC's IP Address
Even though the IP-Address AVP in a PANA-Update-Request can be Even though the IP-Address AVP in a PANA-Update-Request can be
cryptographically protected by the MAC AVP, there is not way to prove cryptographically protected by the MAC AVP, there is not way to prove
the ownership of the IP address presented by the PaC. Hence an the ownership of the IP address presented by the PaC. Hence an
authorized PaC can launch a redirect attack by spoofing a victim's IP authorized PaC can launch a redirect attack by spoofing a victim's IP
address. address.
11.11 Early Termination of a Session 10.10 Early Termination of a Session
The PANA protocol supports the ability for both the PaC and the PAA The PANA protocol supports the ability for both the PaC and the PAA
to transmit a tear-down message before the session lifetime expires. to transmit a tear-down message before the session lifetime expires.
This message causes state removal, a stop of the accounting procedure This message causes state removal, a stop of the accounting procedure
and removes the installed per-PaC state on the EP(s). This message and removes the installed per-PaC state on the EP(s). This message
is cryptographically protected when PANA SA is present. is cryptographically protected when PANA SA is present.
12. Acknowledgments 11. Acknowledgments
We would like to thank Jari Arkko, Mohan Parthasarathy, Julien We would like to thank Jari Arkko, Mohan Parthasarathy, Julien
Bournelle, Rafael Marin Lopez, Pasi Eronen, Randy Turner, Erik Bournelle, Rafael Marin Lopez, Pasi Eronen, Randy Turner, Erik
Nordmark and all members of the PANA working group for their valuable Nordmark, Lionel Morand, Avi Lior, Susan Thomson, Giaretta Gerardo
comments to this document. and all members of the PANA working group for their valuable comments
to this document.
13. References 12. References
13.1 Normative References 12.1 Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC [RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC
2131, March 1997. 2131, March 1997.
[RFC2988] Paxson, V. and M. Allman, "Computing TCP's Retransmission [RFC2988] Paxson, V. and M. Allman, "Computing TCP's Retransmission
Timer", RFC 2988, November 2000. Timer", RFC 2988, November 2000.
skipping to change at page 71, line 44 skipping to change at page 71, line 44
[RFC3456] Patel, B., Aboba, B., Kelly, S. and V. Gupta, "Dynamic [RFC3456] Patel, B., Aboba, B., Kelly, S. and V. Gupta, "Dynamic
Host Configuration Protocol (DHCPv4) Configuration of Host Configuration Protocol (DHCPv4) Configuration of
IPsec Tunnel Mode", RFC 3456, January 2003. IPsec Tunnel Mode", RFC 3456, January 2003.
[RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J. and H. [RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J. and H.
Levkowetz, "Extensible Authentication Protocol (EAP)", RFC Levkowetz, "Extensible Authentication Protocol (EAP)", RFC
3748, June 2004. 3748, June 2004.
[I-D.ietf-eap-keying] [I-D.ietf-eap-keying]
Aboba, B., "Extensible Authentication Protocol (EAP) Key Aboba, B., "Extensible Authentication Protocol (EAP) Key
Management Framework", draft-ietf-eap-keying-03 (work in Management Framework", draft-ietf-eap-keying-04 (work in
progress), July 2004. progress), November 2004.
[IANA] Narten, T. and H. Alvestrand, "Guidelines for Writing an [IANA] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 2434, IANA Considerations Section in RFCs", BCP 26, RFC 2434,
October 1998. October 1998.
13.2 Informative References 12.2 Informative References
[I-D.ietf-pana-requirements] [I-D.ietf-pana-requirements]
Yegin, A. and Y. Ohba, "Protocol for Carrying Yegin, A. and Y. Ohba, "Protocol for Carrying
Authentication for Network Access (PANA)Requirements", Authentication for Network Access (PANA)Requirements",
draft-ietf-pana-requirements-09 (work in progress), August draft-ietf-pana-requirements-09 (work in progress), August
2004. 2004.
[RFC2522] Karn, P. and W. Simpson, "Photuris: Session-Key Management [RFC2522] Karn, P. and W. Simpson, "Photuris: Session-Key Management
Protocol", RFC 2522, March 1999. Protocol", RFC 2522, March 1999.
[I-D.ietf-pana-threats-eval] [I-D.ietf-pana-threats-eval]
Parthasarathy, M., "Protocol for Carrying Authentication Parthasarathy, M., "Protocol for Carrying Authentication
and Network Access Threat Analysis and Security and Network Access Threat Analysis and Security
Requirements", draft-ietf-pana-threats-eval-07 (work in Requirements", draft-ietf-pana-threats-eval-07 (work in
progress), August 2004. progress), August 2004.
[I-D.ietf-pana-ipsec] [I-D.ietf-pana-ipsec]
Parthasarathy, M., "PANA enabling IPsec based Access Parthasarathy, M., "PANA enabling IPsec based Access
Control", draft-ietf-pana-ipsec-04 (work in progress), Control", draft-ietf-pana-ipsec-05 (work in progress),
September 2004. December 2004.
[I-D.ietf-pana-framework] [I-D.ietf-pana-framework]
Jayaraman, P., "PANA Framework", Jayaraman, P., "PANA Framework",
draft-ietf-pana-framework-02 (work in progress), September draft-ietf-pana-framework-02 (work in progress), September
2004. 2004.
[I-D.ietf-pana-snmp] [I-D.ietf-pana-snmp]
Mghazli, Y., Ohba, Y. and J. Bournelle, "SNMP usage for Mghazli, Y., Ohba, Y. and J. Bournelle, "SNMP usage for
PAA-2-EP interface", draft-ietf-pana-snmp-01 (work in PAA-2-EP interface", draft-ietf-pana-snmp-02 (work in
progress), July 2004. progress), October 2004.
[I-D.irtf-aaaarch-handoff]
Arbaugh, W. and B. Aboba, "Experimental Handoff Extension
to RADIUS", draft-irtf-aaaarch-handoff-04 (work in
progress), November 2003.
[I-D.ietf-eap-statemachine] [I-D.ietf-eap-statemachine]
Vollbrecht, J., Eronen, P., Petroni, N. and Y. Ohba, Vollbrecht, J., Eronen, P., Petroni, N. and Y. Ohba,
"State Machines for Extensible Authentication Protocol "State Machines for Extensible Authentication Protocol
(EAP) Peer and Authenticator", (EAP) Peer and Authenticator",
draft-ietf-eap-statemachine-05 (work in progress), draft-ietf-eap-statemachine-05 (work in progress),
September 2004. September 2004.
[I-D.ietf-seamoby-ctp]
Loughney, J., "Context Transfer Protocol",
draft-ietf-seamoby-ctp-11 (work in progress), August 2004.
[I-D.ietf-ipsec-ikev2] [I-D.ietf-ipsec-ikev2]
Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", Kaufman, C., "Internet Key Exchange (IKEv2) Protocol",
draft-ietf-ipsec-ikev2-17 (work in progress), October draft-ietf-ipsec-ikev2-17 (work in progress), October
2004. 2004.
[I-D.ietf-dna-link-information]
Yegin, A., "Link-layer Event Notifications for Detecting
Network Attachments", draft-ietf-dna-link-information-00
(work in progress), September 2004.
[I-D.adrangi-eap-network-discovery]
Adrangi, F., "Mediating Network Discovery in the
Extensible Authentication Protocol (EAP)",
draft-adrangi-eap-network-discovery-07 (work in progress),
December 2004.
[ianaweb] IANA, "Number assignment", http://www.iana.org. [ianaweb] IANA, "Number assignment", http://www.iana.org.
[IANA-EXP] [IANA-EXP]
Narten, T., "Assigning Experimental and Testing Numbers Narten, T., "Assigning Experimental and Testing Numbers
Considered Useful", BCP 82, RFC 3692, January 2004. Considered Useful", BCP 82, RFC 3692, January 2004.
[RFC2279] Yergeau, F., "UTF-8, a transformation format of ISO
10646", RFC 2279, January 1998.
Authors' Addresses Authors' Addresses
Dan Forsberg Dan Forsberg
Nokia Research Center Nokia Research Center
P.O. Box 407 P.O. Box 407
FIN-00045 NOKIA GROUP FIN-00045 NOKIA GROUP
Finland Finland
Phone: +358 50 4839470 Phone: +358 50 4839470
EMail: dan.forsberg@nokia.com EMail: dan.forsberg@nokia.com
skipping to change at page 75, line 4 skipping to change at page 75, line 4
EMail: Hannes.Tschofenig@siemens.com EMail: Hannes.Tschofenig@siemens.com
Alper E. Yegin Alper E. Yegin
Samsung Advanced Institute of Technology Samsung Advanced Institute of Technology
75 West Plumeria Drive 75 West Plumeria Drive
San Jose, CA 95134 San Jose, CA 95134
USA USA
Phone: +1 408 544 5656 Phone: +1 408 544 5656
EMail: alper.yegin@samsung.com EMail: alper.yegin@samsung.com
Appendix A. Example Sequence of Separate NAP and ISP Authentication
A PANA message sequence with separate NAP and ISP authentication is
illustrated in Figure 12. The example assumes the following
scenario:
o The PaC initiates the discovery and handshake phase.
o The PAA offers separate NAP and ISP authentication, as well as a
choice of ISP from "ISP1" and "ISP2". The PaC accepts the offer
from PAA, with choosing "ISP1" as the ISP.
o NAP authentication and ISP authentication is performed in this
order in the authentication and authorization phase.
o An EAP authentication method with a single round trip is used in
each EAP sequence.
o After a PANA SA is established, all messages are integrity and
replay protected with MAC AVPs.
o The access, re-authentication and termination phases are not
shown.
PaC PAA Message(sequence number)[AVPs]
-----------------------------------------------------
// Discovery and handshake phase
-----> PANA-PAA-Discover(0)
<----- PANA-Start-Request(x) // S-flag set
[Nonce, Cookie,
ISP-Information("ISP1"),
ISP-Information("ISP2"),
NAP-Information("MyNAP")]
-----> PANA-Start-Answer(x) // S-flag set
[Nonce, Cookie, // PaC chooses "ISP1"
ISP-Information("ISP1")]
// Authentication and authorization phase
<----- PANA-Auth-Request(x+1) // NAP authentication
[Session-Id, EAP{Request}] // S- and N-flags set
-----> PANA-Auth-Answer(x+1) // S- and N-flags set
[Session-Id] // No piggybacking
-----> PANA-Auth-Request(y) // S- and N-flags set
[Session-Id, EAP{Response}]
<----- PANA-Auth-Answer(y)[Session-Id] // S- and N-flags set
<----- PANA-Auth-Request(x+2) // S- and N-flags set
[Session-Id, EAP{Request}]
-----> PANA-Auth-Answer(x+2) // S- and N-flags set
[Session-Id, EAP{Response}] // Piggybacking
<----- PANA-FirstAuth-End-Request(x+3) // S- and N-flags set
[Session-Id, EAP{Success}, Key-Id, MAC]
-----> PANA-FirstAuth-End-Answer(x+3) // S- and N-flags set
[Session-Id, Key-Id, MAC]
<----- PANA-Auth-Request(x+4) // ISP authentication
[Session-Id, EAP{Request}, MAC] // S-flag set
-----> PANA-Auth-Answer(x+4) // S-flag set
[Session-Id, MAC] // No piggybacking
-----> PANA-Auth-Request(y+1) // S-flag set
[Session-Id, EAP{Response}, MAC]
<----- PANA-Auth-Answer(y+1) // S-flag set
[Session-Id, MAC]
<----- PANA-Auth-Request(x+5) // S-flag set
[Session-Id, EAP{Request}, MAC]
-----> PANA-Auth-Answer(x+5) // S-flag set
[Session-Id, EAP{Response}, MAC] // Piggybacking
<----- PANA-Bind-Request(x+6) // S-flag set
[Session-Id, Result-Code, EAP{Success}, Device-Id,
IP-Address, Key-Id, Lifetime,
Protection-Cap., PPAC, MAC]
-----> PANA-Bind-Answer(x+6) // S-flag set
[Session-Id, Device-Id, Key-Id,
PPAC, MAC]
Figure 12: A Complete Message Sequence for Separate NAP and ISP
Authentication
Intellectual Property Statement Intellectual Property Statement
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Intellectual Property Rights or other rights that might be claimed to Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
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made any independent effort to identify any such rights. Information made any independent effort to identify any such rights. Information
on the procedures with respect to rights in RFC documents can be on the procedures with respect to rights in RFC documents can be
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