draft-ietf-opsawg-capwap-hybridmac-04.txt   draft-ietf-opsawg-capwap-hybridmac-05.txt 
Network Working Group C. Shao Network Working Group C. Shao
Internet-Draft H. Deng Internet-Draft H. Deng
Intended status: Standards Track China Mobile Intended status: Standards Track China Mobile
Expires: November 6, 2014 R. Pazhyannur Expires: January 17, 2015 R. Pazhyannur
Cisco Systems Cisco Systems
F. Bari F. Bari
AT&T AT&T
R. Zhang R. Zhang
China Telecom China Telecom
S. Matsushima S. Matsushima
SoftBank Telecom SoftBank Telecom
May 5, 2014 July 16, 2014
IEEE 802.11 MAC Profile for CAPWAP IEEE 802.11 MAC Profile for CAPWAP
draft-ietf-opsawg-capwap-hybridmac-04 draft-ietf-opsawg-capwap-hybridmac-05
Abstract Abstract
CAPWAP defines two entities: Wireless Transmission Point (WTP) and The CAPWAP protocol defines two entities: a Wireless Transmission
Access Controller (AC). CAPWAP also defines two MAC (Medium Access Point (WTP) and an Access Controller (AC). The CAPWAP protocol
Control) modes for IEEE 802.11 WTPs: Split and Local MAC . For each binding for IEEE 802.11 defines two MAC (Medium Access Control) modes
MAC mode, CAPWAP describes how the MAC functionality is split between for IEEE 802.11 WTP: Split and Local MAC, and describes the required
the WTP and AC. However, certain functions have not been clearly functionality split between the WTP and AC for each mode. However,
defined. For example in the Split MAC mode description, the IEEE in the split MAC mode, the partitioning of encryption/decryption
802.11 encryption is specified as located in either the AC or the WTP functions are not been clearly clearly defined. In the Split MAC
with no clear way for the AC to inform the WTP where it should be. mode description, IEEE 802.11 encryption is specified as located in
This lack of specification leads to interoperability especially when either at the AC or the WTP, with no clear way for the AC to inform
AC and WTP come from different vendors. To solve the problem, this the WTP of where the encryption functionality should be located.
specification defines a IEEE 802.11 MAC profile where each profile This lack of specification leads to interoperability issues,
specifies an unambiguous division of functionality between the WTP especially when the AC and WTP come from different vendors. To
and AC. The IEEE 802.11 MAC profile is used as follows: the WTP prevent interoperability issues, this specification defines an IEEE
informs the AC of the supported profiles during the discovery or join 802.11 MAC profile message element in which each profile specifies an
process and the AC configures the WTP with one of the supported unambiguous division of encryption functionality between the WTP and
profiles while configuring the WLAN. AC. The IEEE 802.11 MAC profile is used as follows: the WTP informs
the AC of the supported profiles during the discovery or join process
and the AC configures the WTP with one of the supported profiles when
configuring the WLAN.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
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material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 6, 2014. This Internet-Draft will expire on January 17, 2015.
Copyright Notice Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 4 2. Conventions used in this document . . . . . . . . . . . . . . 4
3. IEEE MAC Profile Descriptions . . . . . . . . . . . . . . . . 4 3. IEEE MAC Profile Descriptions . . . . . . . . . . . . . . . . 5
3.1. Split MAC with WTP encryption . . . . . . . . . . . . . . 4 3.1. Split MAC with WTP encryption . . . . . . . . . . . . . . 5
3.2. Split MAC with AC encryption . . . . . . . . . . . . . . 5 3.2. Split MAC with AC encryption . . . . . . . . . . . . . . 6
3.3. IEEE 802.11 MAC Profile Frame Exchange . . . . . . . . . 6 3.3. IEEE 802.11 MAC Profile Frame Exchange . . . . . . . . . 7
4. MAC Profile Message Element Definitions . . . . . . . . . . . 7 4. MAC Profile Message Element Definitions . . . . . . . . . . . 8
4.1. IEEE 802.11 Supported MAC Profiles . . . . . . . . . . . 7 4.1. IEEE 802.11 Supported MAC Profiles . . . . . . . . . . . 8
4.2. IEEE 802.11 MAC Profile . . . . . . . . . . . . . . . . . 8 4.2. IEEE 802.11 MAC Profile . . . . . . . . . . . . . . . . . 9
5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 9
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 9 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 10
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10
9. Normative References . . . . . . . . . . . . . . . . . . . . 9 9. Normative References . . . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
The CAPWAP protocol supports two MAC modes of operation: Split and The CAPWAP protocol supports two MAC modes of operation: Split and
Local MAC, as described in [RFC5415], [RFC5416]. However, there are Local MAC, as described in [RFC5415], [RFC5416]. However, there are
MAC functions that have not been clearly defined. For example IEEE MAC functions that have not been clearly defined. For example IEEE
802.11 encryption is specified as located in either in the AC or the 802.11 encryption is specified as located in either in the AC or the
WTP with no clear way to negotiate where it should be located. WTP with no clear way to negotiate where it should be located.
Because different vendors have their own definition of the MAC mode, Because different vendors have different definitions of the MAC mode,
many MAC layer functions are mapped differently to either the WTP or many MAC layer functions are mapped differently to either the WTP or
the AC by different vendors. Therefore, depending upon the vendor, the AC by different vendors. Therefore, depending upon the vendor,
the operators in their deployments have to perform different the operators in their deployments have to perform different
configurations based on implementation of the two modes by their configurations based on implementation of the two modes by their
vendor. If there is no clear specification then operators will vendor. If there is no clear specification, then operators will
experience difficulty in interoperating WTPs and ACs from different experience interoperability issues with WTPs and ACs from different
vendors. vendors."
Figure 1 is quoted from [RFC5416], illustrates how the functions are Figure 1 from [RFC5416], illustrates how some functions are processed
processed in different places in the Local MAC and Split MAC mode. in different places in the Local MAC and Split MAC mode.
Specifically, note that in the Split MAC mode the IEEE 802.11 Specifically, note that in the Split MAC mode the IEEE 802.11
encryption/decryption is specified as WTP/AC implying that it could encryption/decryption is specified as WTP/AC implying that it could
be at either location. be at either location.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Functions | Local MAC | Split MAC | | Functions | Local MAC | Split MAC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Distribution Service | WTP/AC | AC | | |Distribution Service | WTP/AC | AC |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Integration Service | WTP | AC | | |Integration Service | WTP | AC |
skipping to change at page 3, line 41 skipping to change at page 4, line 30
+ |/Defragmentation | | | + |/Defragmentation | | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Assoc/Disassoc/Reassoc | WTP/AC | AC | | |Assoc/Disassoc/Reassoc | WTP/AC | AC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Classifying | WTP | AC | | |Classifying | WTP | AC |
+ IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 QoS |Scheduling | WTP | WTP/AC | | 802.11 QoS |Scheduling | WTP | WTP/AC |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Queuing | WTP | WTP | | |Queuing | WTP | WTP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |IEEE 802.1X/EWTP | AC | AC | | |IEEE 802.1X/EAP | AC | AC |
+ IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 RSN |RSNA Key Management | AC | AC | | 802.11 RSN |RSNA Key Management | AC | AC |
+ (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |IEEE 802.11 | WTP | WTP/AC | | |IEEE 802.11 | WTP | WTP/AC |
+ |Encryption/Decryption | | | + |Encryption/Decryption | | |
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Functions in Local MAC and Split MAC Figure 1: Functions in Local MAC and Split MAC
To solve this problem, this specification introduces IEEE 802.11 MAC To solve this problem, this specification introduces IEEE 802.11 MAC
skipping to change at page 4, line 24 skipping to change at page 5, line 14
3. IEEE MAC Profile Descriptions 3. IEEE MAC Profile Descriptions
A IEEE MAC Profile refers to a description of how the MAC A IEEE MAC Profile refers to a description of how the MAC
functionality is split between the WTP and AC shown in Figure 1. functionality is split between the WTP and AC shown in Figure 1.
3.1. Split MAC with WTP encryption 3.1. Split MAC with WTP encryption
The functional split for the Split MAC with WTP encryption is The functional split for the Split MAC with WTP encryption is
provided in Figure 2. This profile is similar to the Split MAC provided in Figure 2. This profile is similar to the Split MAC
description in [RFC5416] except that IEEE 802.11 encryption/ description in [RFC5416], except that IEEE 802.11 encryption/
decryption is at the WTP. Note that fragmentation is always done at decryption is at the WTP. Note that fragmentation is always done at
the same entity as the encryption. Consequently, in this profile the same entity as the encryption. Consequently, in this profile
fragmentation/defragmentation is also done only at the WTP Note that fragmentation/defragmentation is also done only at the WTP. Note
scheduling functionality is denoted as WTP/AC. As explained in that scheduling functionality is denoted as WTP/AC. As explained in
[RFC5416], this means that the admission control component of IEEE [RFC5416], this means that the admission control component of IEEE
802.11 resides on the AC, the real-time scheduling and queuing 802.11 resides on the AC, the real-time scheduling and queuing
functions are on the WTP. functions are on the WTP.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Functions | Profile | | Functions | Profile |
| | 0 | | | 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Distribution Service | AC | | |Distribution Service | AC |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 5, line 31 skipping to change at page 6, line 31
+ |/Defragmentation | | + |/Defragmentation | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Assoc/Disassoc/Reassoc | AC | | |Assoc/Disassoc/Reassoc | AC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Classifying | AC | | |Classifying | AC |
+ IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 QoS |Scheduling | WTP/AC | | 802.11 QoS |Scheduling | WTP/AC |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Queuing | WTP | | |Queuing | WTP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |IEEE 802.1X/EWTP | AC | | |IEEE 802.1X/EAP | AC |
+ IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 RSN |RSNA Key Management | AC | | 802.11 RSN |RSNA Key Management | AC |
+ (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |IEEE 802.11 | WTP | | |IEEE 802.11 | WTP |
+ |Encryption/Decryption | | + |Encryption/Decryption | |
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: Functions in Split MAC with WTP Encryption Figure 2: Functions in Split MAC with WTP Encryption
3.2. Split MAC with AC encryption 3.2. Split MAC with AC encryption
skipping to change at page 6, line 31 skipping to change at page 7, line 31
+ |/Defragmentation | | + |/Defragmentation | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Assoc/Disassoc/Reassoc | AC | | |Assoc/Disassoc/Reassoc | AC |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Classifying | AC | | |Classifying | AC |
+ IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 QoS |Scheduling | WTP | | 802.11 QoS |Scheduling | WTP |
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |Queuing | WTP | | |Queuing | WTP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |IEEE 802.1X/EWTP | AC | | |IEEE 802.1X/EAP | AC |
+ IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + IEEE +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 802.11 RSN |RSNA Key Management | AC | | 802.11 RSN |RSNA Key Management | AC |
+ (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + (WPA2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |IEEE 802.11 | AC | | |IEEE 802.11 | AC |
+ |Encryption/Decryption | | + |Encryption/Decryption | |
|-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: Functions in Split MAC with AC encryption Figure 3: Functions in Split MAC with AC encryption
3.3. IEEE 802.11 MAC Profile Frame Exchange 3.3. IEEE 802.11 MAC Profile Frame Exchange
skipping to change at page 8, line 32 skipping to change at page 9, line 32
* 1: This refers to the Split MAC Profile with AC encryption * 1: This refers to the Split MAC Profile with AC encryption
5. Security Considerations 5. Security Considerations
This document does not introduce any new security risks compared to This document does not introduce any new security risks compared to
[RFC5416]. The security considerations described in [RFC5416] apply [RFC5416]. The security considerations described in [RFC5416] apply
here as well. here as well.
6. IANA Considerations 6. IANA Considerations
This document requires the following IANA actions. This document requires the following IANA actions:
o This specification defines a new message element, IEEE 802.11 o This specification defines two new message elements, IEEE 802.11
Supported MAC Profiles. The format of this option is described in Supported MAC Profiles (described in Section 4.1) and IEEE 802.11
Section 4.1. This value needs to be registered in the existing MAC Profile (described in Section 4.2). These elements needs to
CAPWAP Message Element Type registry, defined in [RFC5415]. be registered in the existing CAPWAP Message Element Type
o This specification defines a new message element, IEEE 802.11 MAC registry, defined in [RFC5415]. The values for these elements
Profile. The format of this option is described in Section 4.2. needs to be between 1024 and 2047 (see Section 15.7 in [RFC5415]).
This value needs to be registered in the existing CAPWAP Message
Element Type registry, defined in [RFC5415]. CAPWAP Protocol Message Element Type Value
o The Profile field in the IEEE 802.11 Supported MAC Profiles IEEE 802.11 Supported MAC Profiles TBD1
message element and IEEE 802.11 MAC Profile message element (see IEEE 802.11 MAC Profile TBD2
Section 4.2) is used to denote the MAC profile. This document o The IEEE 802.11 Supported MAC Profiles message element and IEEE
defines two values, zero (0) and one (1), and the remaining values 802.11 MAC Profile message element include a Profile Field (as
(2-255) are controlled and maintained by IANA and require an defined in Section 4.2). The Profile field in the IEEE 802.11
Expert Review. Supported MAC Profiles denotes the MAC profiles supported by the
WTP. The profile field in the IEEE MAC profile denotes MAC
profile assigned to the WTP. The namespace for the field is 8
bits (0-255). This specification defines two values, zero (0) and
one (1) as described below. The remaining values (2-255) are
controlled and maintained by IANA and require an Expert Review.
IANA needs to create a registry whose format is given below.
Profile Type Value Reference
Split MAC with WTP encryption 0
Split MAC with AC encryption 1
7. Contributors 7. Contributors
Yifan Chen chenyifan@chinamobile.com Yifan Chen chenyifan@chinamobile.com
Naibao Zhou zhounaibao@chinamobile.com Naibao Zhou zhounaibao@chinamobile.com
8. Acknowledgments 8. Acknowledgments
The authors are grateful for extremely valuable suggestions from The authors are grateful for extremely valuable suggestions from
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