draft-ietf-speermint-architecture-19.txt   rfc6406.txt 
SPEERMINT D. Malas, Ed. Internet Engineering Task Force (IETF) D. Malas, Ed.
Internet-Draft CableLabs Request for Comments: 6406 CableLabs
Intended status: Informational J. Livingood, Ed. Category: Informational J. Livingood, Ed.
Expires: August 22, 2011 Comcast ISSN: 2070-1721 Comcast
February 18, 2011 November 2011
Session PEERing for Multimedia INTerconnect Architecture Session PEERing for Multimedia INTerconnect (SPEERMINT) Architecture
draft-ietf-speermint-architecture-19
Abstract Abstract
This document defines a peering architecture for the Session This document defines a peering architecture for the Session
Initiation Protocol (SIP), its functional components and interfaces. Initiation Protocol (SIP) and its functional components and
It also describes the components and the steps necessary to establish interfaces. It also describes the components and the steps necessary
a session between two SIP Service Provider (SSP) peering domains. to establish a session between two SIP Service Provider (SSP) peering
domains.
Status of this Memo
This Internet-Draft is submitted in full conformance with the Status of This Memo
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering This document is not an Internet Standards Track specification; it is
Task Force (IETF). Note that other groups may also distribute published for informational purposes.
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 5741.
This Internet-Draft will expire on August 22, 2011. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6406.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
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publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 3, line 7 skipping to change at page 2, line 19
modifications of such material outside the IETF Standards Process. modifications of such material outside the IETF Standards Process.
Without obtaining an adequate license from the person(s) controlling Without obtaining an adequate license from the person(s) controlling
the copyright in such materials, this document may not be modified the copyright in such materials, this document may not be modified
outside the IETF Standards Process, and derivative works of it may outside the IETF Standards Process, and derivative works of it may
not be created outside the IETF Standards Process, except to format not be created outside the IETF Standards Process, except to format
it for publication as an RFC or to translate it into languages other it for publication as an RFC or to translate it into languages other
than English. than English.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction ....................................................3
2. New Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 2. New Terminology .................................................3
2.1. Session Border Controller (SBC) . . . . . . . . . . . . . 4 2.1. Session Border Controller (SBC) ............................3
2.2. Carrier-of-Record . . . . . . . . . . . . . . . . . . . . 5 2.2. Carrier-of-Record ..........................................4
3. Reference Architecture . . . . . . . . . . . . . . . . . . . . 5 3. Reference Architecture ..........................................4
4. Procedures of Inter-Domain SSP Session Establishment . . . . . 7 4. Procedures of Inter-Domain SSP Session Establishment ............6
5. Relationships Between Functions/Elements . . . . . . . . . . . 8 5. Relationships between Functions/Elements ........................7
6. Recommended SSP Procedures . . . . . . . . . . . . . . . . . . 8 6. Recommended SSP Procedures ......................................7
6.1. Originating or Indirect SSP Procedures . . . . . . . . . . 8 6.1. Originating or Indirect SSP Procedures .....................7
6.1.1. The Look-Up Function (LUF) . . . . . . . . . . . . . . 9 6.1.1. The Lookup Function (LUF) ...........................8
6.1.1.1. Target Address Analysis . . . . . . . . . . . . . 9 6.1.1.1. Target Address Analysis ....................8
6.1.1.2. ENUM Lookup . . . . . . . . . . . . . . . . . . . 9 6.1.1.2. ENUM Lookup ................................8
6.1.2. Location Routing Function (LRF) . . . . . . . . . . . 10 6.1.2. Location Routing Function (LRF) .....................9
6.1.2.1. DNS Resolution . . . . . . . . . . . . . . . . . . 10 6.1.2.1. DNS Resolution .............................9
6.1.2.2. Routing Table . . . . . . . . . . . . . . . . . . 10 6.1.2.2. Routing Table ..............................9
6.1.2.3. LRF to LRF Routing . . . . . . . . . . . . . . . . 11 6.1.2.3. LRF to LRF Routing ........................10
6.1.3. The Signaling Path Border Element (SBE) . . . . . . . 11 6.1.3. The Signaling Path Border Element (SBE) ............10
6.1.3.1. Establishing a Trusted Relationship . . . . . . . 11 6.1.3.1. Establishing a Trusted Relationship .......10
6.1.3.2. IPSec . . . . . . . . . . . . . . . . . . . . . . 11 6.1.3.2. IPsec .....................................10
6.1.3.3. Co-Location . . . . . . . . . . . . . . . . . . . 11 6.1.3.3. Co-Location ...............................11
6.1.3.4. Sending the SIP Request . . . . . . . . . . . . . 12 6.1.3.4. Sending the SIP Request ...................11
6.2. Target SSP Procedures . . . . . . . . . . . . . . . . . . 12 6.2. Target SSP Procedures .....................................11
6.2.1. TLS . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.2.1. TLS ................................................11
6.2.2. Receive SIP Requests . . . . . . . . . . . . . . . . . 12 6.2.2. Receive SIP Requests ...............................11
6.3. Data Path Border Element (DBE) . . . . . . . . . . . . . . 13 6.3. Data Path Border Element (DBE) ............................12
7. Address Space Considerations . . . . . . . . . . . . . . . . . 13 7. Address Space Considerations ...................................12
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 8. Acknowledgments ................................................12
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 9. Security Considerations ........................................12
10. Security Considerations . . . . . . . . . . . . . . . . . . . 13 10. Contributors ..................................................13
11. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 14 11. References ....................................................14
12. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . . 15 11.1. Normative References .....................................14
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16 11.2. Informative References ...................................15
13.1. Normative References . . . . . . . . . . . . . . . . . . . 16
13.2. Informative References . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction 1. Introduction
This document defines a reference peering architecture for the This document defines a reference peering architecture for the
Session Initiation Protocol (SIP)[RFC3261], it's functional Session Initiation Protocol (SIP) [RFC3261], it's functional
components and interfaces, in the context of session peering for components and interfaces in the context of session peering for
multimedia interconnects. In this process, we define the peering multimedia interconnects. In this process, we define the peering
reference architecture, its functional components, and peering reference architecture and its functional components, and peering
interface functions from the perspective of a SIP Service Provider's interface functions from the perspective of a SIP Service Provider's
(SSP) [RFC5486] network. Thus, it also describes the components and (SSP's) [RFC5486] network. Thus, it also describes the components
the steps necessary to establish a session between two SSP peering and the steps necessary to establish a session between two SSP
domains. peering domains.
An SSP may also be referred to as an Internet Telephony Service An SSP may also be referred to as an Internet Telephony Service
Provider (ITSP). While the terms ITSP and SSP are frequently used Provider (ITSP). While the terms ITSP and SSP are frequently used
interchangeably, this document and other subsequent SIP peering- interchangeably, this document and other subsequent SIP peering-
related documents should use the term SSP. SSP more accurately related documents should use the term SSP. SSP more accurately
depicts the use of SIP as the underlying layer 5 signaling protocol. depicts the use of SIP as the underlying Layer 5 signaling protocol.
This architecture enables the interconnection of two SSPs in layer 5 This architecture enables the interconnection of two SSPs in Layer 5
peering, as defined in the SIP-based session peering requirements peering, as defined in the SIP-based session peering requirements
[I-D.ietf-speermint-requirements]. [RFC6271].
Layer 3 peering is outside the scope of this document. Hence, the Layer 3 peering is outside the scope of this document. Hence, the
figures in this document do not show routers so that the focus is on figures in this document do not show routers so that the focus is on
layer 5 protocol aspects. Layer 5 protocol aspects.
This document uses terminology defined in the Session Peering for This document uses terminology defined in "Session Peering for
Multimedia Interconnect (SPEERMINT) Terminology document [RFC5486]. Multimedia Interconnect (SPEERMINT) Terminology" [RFC5486]. In
Apart from normative references included herein, readers may also addition to normative references included herein, readers may also
find [I-D.ietf-speermint-voip-consolidated-usecases] informative. find [RFC6405] informative.
2. New Terminology 2. New Terminology
[RFC5486] is a key reference for the majority of the SPEERMINT- [RFC5486] is a key reference for the majority of the SPEERMINT-
related terminology used in this document. However, some additional related terminology used in this document. However, some additional
new terms are used here as follows in this section. new terms are used here as follows in this section.
2.1. Session Border Controller (SBC) 2.1. Session Border Controller (SBC)
A Session Border Controller (SBC) is referred to in Section 5. An A Session Border Controller (SBC) is referred to in Section 5. An
SBC can contain a Signaling Function (SF), Signaling Path Border SBC can contain a Signaling Function (SF), Signaling Path Border
Element (SBE) and Data Path Border Element (DBE), and may perform the Element (SBE) and Data Path Border Element (DBE), and may perform the
Look-Up Function (LUF) and Location Routing Function (LRF) functions, Lookup Function (LUF) and Location Routing Function (LRF), as
as described in Section 3. Whether the SBC performs one or more of described in Section 3. Whether the SBC performs one or more of
these functions is generally speaking dependent upon how a SIP these functions is, generally speaking, dependent upon how a SIP
Service Provider (SSP) configures such a network element. In Service Provider (SSP) configures such a network element. In
addition, requirements for an SBC can be found in [RFC5853]. addition, requirements for an SBC can be found in [RFC5853].
2.2. Carrier-of-Record 2.2. Carrier-of-Record
A carrier-of-record, as used in Section 6.1.2.2, is defined in A carrier-of-record, as used in Section 6.1.2.2, is defined in
[RFC5067]. That document describes the term to refer to the entity [RFC5067]. That document describes the term as referring to the
having discretion over the domain and zone content and acting as the entity having discretion over the domain and zone content and acting
registrant for a telephone number, as represented in ENUM. This can as the registrant for a telephone number, as represented in ENUM.
be: This can be as follows:
o the Service Provider to which the E.164 number was allocated for o the service provider to which the E.164 number was allocated for
end user assignment, whether by the National Regulatory Authority end user assignment, whether by the National Regulatory Authority
(NRA) or the International Telecommunication Union (ITU), for (NRA) or the International Telecommunication Union (ITU), for
instance, a code under "International Networks" (+882) or instance, a code under "International Networks" (+882) or
"Universal Personal Telecommunications (UPT)" (+878) or, "Universal Personal Telecommunications (UPT)" (+878), or
o if the number is ported, the service provider to which the number o if the number is ported, the service provider to which the number
was ported, or was ported, or
o where numbers are assigned directly to end users, the service o where numbers are assigned directly to end users, the service
provider that the end user number assignee has chosen to provide a provider that the end user number assignee has chosen to provide a
Public Switched Telephone Network/Public Land Mobile Network Public Switched Telephone Network / Public Land Mobile Network
(PSTN/ PLMN) point-of-interconnect for the number. (PSTN/PLMN) point-of-interconnect for the number.
It is understood that the definition of carrier-of-record within a It is understood that the definition of "carrier-of-record" within a
given jurisdiction is subject to modification by national given jurisdiction is subject to modification by national
authorities. authorities.
3. Reference Architecture 3. Reference Architecture
The following figure depicts the architecture and logical functions The following figure depicts the architecture and logical functions
that form peering between two SSPs. that form peering between two SSPs.
For further details on the elements and functions described in this For further details on the elements and functions described in this
figure, please refer to [RFC5486]. The following terms, which appear figure, please refer to [RFC5486]. The following terms, which appear
in Figure 1, which are documented in [RFC5486] are reproduced here in Figure 1 and are documented in [RFC5486], are reproduced here for
for simplicity. simplicity.
- Data Path Border Element (DBE): A data path border element (DBE) is o Data Path Border Element (DBE): A data path border element (DBE)
located on the administrative border of a domain through which flows is located on the administrative border of a domain through which
the media associated with an inter-domain session. It typically the media associated with an inter-domain session flows.
provides media-related functions such as deep packet inspection and Typically, it provides media-related functions such as deep packet
modification, media relay, and firewall-traversal support. The DBE inspection and modification, media relay, and firewall-traversal
may be controlled by the SBE. support. The DBE may be controlled by the SBE.
- E.164 Number Mapping (ENUM): See [RFC3761]. o E.164 Number Mapping (ENUM): See [RFC6116].
- Fully Qualified Domain Name (FQDN): See Section 5.1 of [RFC1035]. o Fully Qualified Domain Name (FQDN): See [RFC1035].
- Location Routing Function (LRF): The Location Routing Function o Location Routing Function (LRF): The Location Routing Function
(LRF) determines for the target domain of a given request the (LRF) determines, for the target domain of a given request, the
location of the SF in that domain, and optionally develops other SED location of the SF in that domain, and optionally develops other
required to route the request to that domain. An example of the LRF Session Establishment Data (SED) required to route the request to
may be applied to either example in Section 4.3.3 of [RFC5486]. Once that domain. An example of the LRF may be applied to either
the ENUM response or SIP 302 redirect is received with the example in Section 4.3.3 of [RFC5486]. Once the ENUM response or
destination's SIP URI, the LRF must derive the destination peer's SF SIP 302 redirect is received with the destination's SIP URI, the
from the FQDN in the domain portion of the URI. In some cases, some LRF must derive the destination peer's SF from the FQDN in the
entity (usually a 3rd party or federation) provides peering domain portion of the URI. In some cases, some entity (usually a
assistance to the originating SSP by providing this function. The third party or federation) provides peering assistance to the
assisting entity may provide information relating to direct (Section Originating SSP by providing this function. The assisting entity
4.2.1 of [RFC5486]) or indirect (Section 4.2.2 of [RFC5486]) peering may provide information relating to direct (Section 4.2.1 of
as necessary. [RFC5486]) or indirect (Section 4.2.2 of [RFC5486]) peering as
necessary.
- Look-Up Function (LUF): The Look-Up Function (LUF) determines for a o Lookup Function (LUF): The Lookup Function (LUF) determines, for a
given request the target domain to which the request should be given request, the target domain to which the request should be
routed. An example of an LUF is an ENUM [4] look-up or a SIP INVITE routed. An example of an LUF is an ENUM [4] look-up or a SIP
request to a SIP proxy providing redirect responses for peers. In INVITE request to a SIP proxy providing redirect responses for
some cases, some entity (usually a 3rd party or federation) provides peers. In some cases, some entity (usually a third party or
peering assistance to the originating SSP by providing this function. federation) provides peering assistance to the Originating SSP by
The assisting entity may provide information relating to direct providing this function. The assisting entity may provide
(Section 4.2.1 of [RFC5486]) or indirect (Section 4.2.2 of [RFC5486]) information relating to direct (Section 4.2.1 of [RFC5486]) or
peering as necessary. indirect (Section 4.2.2 of [RFC5486]) peering as necessary.
- Real-Time Transport Protocol (RTP): See [RFC3550]. o Real-time Transport Protocol (RTP): See [RFC3550].
- Session Initiation Protocol (SIP): See [RFC3261]. o Session Initiation Protocol (SIP): See [RFC3261].
- Signaling Path Border Element (SBE): A signaling path border o Signaling Path Border Element (SBE): A signaling path border
element (SBE) is located on the administrative border of a domain element (SBE) is located on the administrative border of a domain
through which inter-domain session layer messages will flow. It through which inter-domain session-layer messages will flow.
typically provides signaling functions such as protocol inter-working Typically, it provides Signaling Functions such as protocol inter-
(for example, H.323 to SIP), identity and topology hiding, and working (for example, H.323 to SIP), identity and topology hiding,
Session Admission Control for a domain. and Session Admission Control for a domain.
- Signaling Function (SF): The Signaling Function (SF) performs o Signaling Function (SF): The Signaling Function (SF) performs
routing of SIP requests for establishing and maintaining calls, and routing of SIP requests for establishing and maintaining calls and
to assist in the discovery or exchange of parameters to be used by in order to assist in the discovery or exchange of parameters to
the Media Function (MF). The SF is a capability of SIP processing be used by the Media Function (MF). The SF is a capability of SIP
elements such as SIP proxies, SBEs, and user agents. processing elements such as SIP proxies, SBEs, and User Agents.
- SIP Service Provider (SSP): A SIP Service Provider (SSP) is an o SIP Service Provider (SSP): A SIP Service Provider (SSP) is an
entity that provides session services utilizing SIP signaling to its entity that provides session services utilizing SIP signaling to
customers. In the event that the SSP is also a function of the SP, its customers. In the event that the SSP is also a function of
it may also provide media streams to its customers. Such an SSP may the SP, it may also provide media streams to its customers. Such
additionally be peered with other SSPs. An SSP may also interconnect an SSP may additionally be peered with other SSPs. An SSP may
with the PSTN. also interconnect with the PSTN.
+=============++ ++=============+ +=============++ ++=============+
|| || || ||
+-----------+ +-----------+ +-----------+ +-----------+
| SBE | +-----+ | SBE | | SBE | +-----+ | SBE |
| +-----+ | SIP |Proxy| | +-----+ | | +-----+ | SIP |Proxy| | +-----+ |
| | LUF |<-|------>|ENUM | | | LUF | | | | LUF |<-|------>|ENUM | | | LUF | |
| +-----+ | ENUM |TN DB| | +-----+ | | +-----+ | ENUM |TN DB| | +-----+ |
SIP | | +-----+ | | SIP | | +-----+ | |
------>| +-----+ | DNS +-----+ | +-----+ | ------>| +-----+ | DNS +-----+ | +-----+ |
skipping to change at page 7, line 36 skipping to change at page 6, line 36
SSP1 Network || || SSP2 Network SSP1 Network || || SSP2 Network
+=============++ ++=============+ +=============++ ++=============+
Reference Architecture Reference Architecture
Figure 1 Figure 1
4. Procedures of Inter-Domain SSP Session Establishment 4. Procedures of Inter-Domain SSP Session Establishment
This document assumes that in order for a session to be established This document assumes that in order for a session to be established
from a User Agent (UA) in the originating (or indirect) SSP's network from a User Agent (UA) in the Originating (or Indirect) SSP's network
to an UA in the Target SSP's network the following steps are taken: to a UA in the Target SSP's network the following steps are taken:
1. Determine the target or indirect SSP via the LUF. (Note: If the 1. Determine the Target or Indirect SSP via the LUF. (Note: If the
target address represents an intra-SSP resource, the behavior is target address represents an intra-SSP resource, the behavior is
out-of-scope with respect to this draft.) out of scope with respect to this document.)
2. Determine the address of the SF of the target SSP via the LRF. 2. Determine the address of the SF of the Target SSP via the LRF.
3. Establish the session 3. Establish the session.
4. Exchange the media, which could include voice, video, text, etc. 4. Exchange the media, which could include voice, video, text, etc.
5. End the session (BYE) 5. End the session (BYE)
The originating or indirect SSP would perform steps 1-4, the target The Originating or Indirect SSP would perform steps 1-4, the Target
SSP would perform steps 4, and either one can perform step 5. SSP would perform step 4, and either one can perform step 5.
In the case the target SSP changes, then steps 1-4 would be repeated. In the case that the Target SSP changes, steps 1-4 would be repeated.
This is reflected in Figure 1 that shows the target SSP with its own This is reflected in Figure 1, which shows the Target SSP with its
peering functions. own peering functions.
5. Relationships Between Functions/Elements 5. Relationships between Functions/Elements
Please also refer to Figure 1. Please also refer to Figure 1.
o An SBE can contain a Signaling Function (SF). o An SBE can contain a Signaling Function (SF).
o An SF can perform a Look-Up Function (LUF) and Location Routing o An SF can perform a Lookup Function (LUF) and Location Routing
Function (LRF). Function (LRF).
o As an additional consideration, a Session Border Controller, can o As an additional consideration, a Session Border Controller, can
contain an SF, SBE and DBE, and may act as both an LUF and LRF. contain an SF, SBE and DBE, and may act as both an LUF and LRF.
o The following functions may communicate as follows in an example o The following functions may communicate as follows in an example
SSP network, depending upon various real-world implementations: SSP network, depending upon various real-world implementations:
* SF may communicate with LUF, LRF, SBE and SF * SF may communicate with the LUF, LRF, SBE, and SF
* LUF may communicate with SF and SBE * LUF may communicate with the SF and SBE
* LRF may communicate with SF and SBE * LRF may communicate with the SF and SBE
6. Recommended SSP Procedures 6. Recommended SSP Procedures
This section describes the functions in more detail and provides some This section describes the functions in more detail and provides some
recommendations on the role they would play in a SIP call in a Layer recommendations on the role they would play in a SIP call in a Layer
5 peering scenario. 5 peering scenario.
Some of the information in the section is taken from Some of the information in this section is taken from [RFC6271] and
[I-D.ietf-speermint-requirements] and is included here for continuity is included here for continuity purposes. It is also important to
purposes. It is also important to refer to Section 3.2 of refer to Section 3.2 of [RFC6404], particularly with respect to the
[I-D.ietf-speermint-voipthreats], particularly with respect to the use of IPsec and TLS.
use of IPSec and TLS.
6.1. Originating or Indirect SSP Procedures 6.1. Originating or Indirect SSP Procedures
This section describes the procedures of the originating or indirect This section describes the procedures of the Originating or indirect
SSP. SSP.
6.1.1. The Look-Up Function (LUF) 6.1.1. The Lookup Function (LUF)
The purpose of the LUF is to determine the SF of the target domain of The purpose of the LUF is to determine the SF of the target domain of
a given request and optionally to develop Session Establishment Data. a given request and optionally to develop Session Establishment Data.
It is important to note that the LUF may utilize the public e164.arpa It is important to note that the LUF may utilize the public e164.arpa
ENUM root, as well as one or more private roots. When private roots ENUM root, as well as one or more private roots. When private roots
are used specialized routing rules may be implemented, and these are used, specialized routing rules may be implemented; these rules
rules may vary depending upon whether an originating or indirect SSP may vary depending upon whether an Originating or Indirect SSP is
is querying the LUF. querying the LUF.
6.1.1.1. Target Address Analysis 6.1.1.1. Target Address Analysis
When the originating (or indirect) SSP receives a request to When the Originating (or Indirect) SSP receives a request to
communicate, it analyzes the target URI to determine whether the call communicate, it analyzes the target URI to determine whether the call
needs to be routed internal or external to its network. The analysis needs to be routed internally or externally to its network. The
method is internal to the SSP; thus, outside the scope of SPEERMINT. analysis method is internal to the SSP; thus, outside the scope of
SPEERMINT.
If the target address does not represent a resource inside the If the target address does not represent a resource inside the
originating (or indirect) SSP's administrative domain or federation Originating (or Indirect) SSP's administrative domain or federation
of domains, then the originating (or indirect) SSP performs a Lookup of domains, then the Originating (or Indirect) SSP performs a Lookup
Function (LUF) to determine a target address, and then it resolves Function (LUF) to determine a target address, and then it resolves
the call routing data by using the Location routing Function (LRF). the call routing data by using the Location Routing Function (LRF).
For example, if the request to communicate is for an im: or pres: URI For example, if the request to communicate is for an im: or pres: URI
type [RFC3861] [RFC3953], the originating (or indirect) SSP follows type [RFC3861] [RFC3953], the Originating (or Indirect) SSP follows
the procedures in [RFC3861]. If the highest priority supported URI the procedures in [RFC3861]. If the highest priority supported URI
scheme is sip: or sips: the originating (or indirect) SSP skips to scheme is sip: or sips:, the Originating (or Indirect) SSP skips to
SIP DNS resolution in Section 5.1.3. Likewise, if the target address SIP DNS resolution in Section 5.1.3. Likewise, if the target address
is already a sip: or sips: URI in an external domain, the originating is already a sip: or sips: URI in an external domain, the Originating
(or indirect) SSP skips to SIP DNS resolution in Section 6.1.2.1. (or Indirect) SSP skips to SIP DNS resolution in Section 6.1.2.1.
This may be the case, to use one example, with This may be the case, to use one example, with
"sips:bob@biloxi.example.com". "sips:bob@biloxi.example.com".
If the target address corresponds to a specific E.164 address, the If the target address corresponds to a specific E.164 address, the
SSP may need to perform some form of number plan mapping according to SSP may need to perform some form of number plan mapping according to
local policy. For example, in the United States, a dial string local policy. For example, in the United States, a dial string
beginning "011 44" could be converted to "+44", or in the United beginning "011 44" could be converted to "+44"; in the United
Kingdom "00 1" could be converted to "+1". Once the SSP has an E.164 Kingdom, "00 1" could be converted to "+1". Once the SSP has an
address, it can use ENUM. E.164 address, it can use ENUM.
6.1.1.2. ENUM Lookup 6.1.1.2. ENUM Lookup
If an external E.164 address is the target, the originating (or If an external E.164 address is the target, the Originating (or
indirect) SSP consults the public "User ENUM" rooted at e164.arpa, Indirect) SSP consults the public "User ENUM" rooted at e164.arpa,
according to the procedures described in [RFC3761]. The SSP must according to the procedures described in [RFC6116]. The SSP must
query for the "E2U+sip" enumservice as described in [RFC3764], but query for the "E2U+sip" enumservice as described in [RFC3764], but
may check for other enumservices. The originating (or indirect) SSP may check for other enumservices. The Originating (or Indirect) SSP
may consult a cache or alternate representation of the ENUM data may consult a cache or alternate representation of the ENUM data
rather than actual DNS queries. Also, the SSP may skip actual DNS rather than actual DNS queries. Also, the SSP may skip actual DNS
queries if the originating (or indirect) SSP is sure that the target queries if the Originating (or Indirect) SSP is sure that the target
address country code is not represented in e164.arpa. address country code is not represented in e164.arpa.
If an im: or pres: URI is chosen based on an "E2U+im" [RFC3861] or If an im: or pres: URI is chosen based on an "E2U+im" [RFC3861] or
"E2U+pres" [RFC3953] enumserver, the SSP follows the procedures for "E2U+pres" [RFC3953] enumserver, the SSP follows the procedures for
resolving these URIs to URIs for specific protocols such as SIP or resolving these URIs to URIs for specific protocols such as SIP or
XMPP as described in the previous section. Extensible Messaging and Presence Protocol (XMPP) as described in the
previous section.
The NAPTR response to the ENUM lookup may be a SIP AoR (such as The Naming Authority Pointer (NAPTR) response to the ENUM lookup may
"sips:bob@example.com") or SIP URI (such as be a SIP address of record (AOR) (such as "sips:bob@example.com") or
"sips:bob@sbe1.biloxi.example.com"). In the case of when a SIP URI SIP URI (such as "sips:bob@sbe1.biloxi.example.com"). In the case
is returned, the originating (or indirect) SSP has sufficient routing when a SIP URI is returned, the Originating (or Indirect) SSP has
information to locate the target SSP. In the case of when a SIP AoR sufficient routing information to locate the Target SSP. In the case
is returned, the SF then uses the LRF to determine the URI for more of when a SIP AoR is returned, the SF then uses the LRF to determine
explicitly locating the target SSP. the URI for more explicitly locating the Target SSP.
6.1.2. Location Routing Function (LRF) 6.1.2. Location Routing Function (LRF)
The LRF of an originating (or indirect) SSP analyzes target address The LRF of an Originating (or Indirect) SSP analyzes target address
and target domain identified by the LUF, and discovers the next hop and target domain identified by the LUF, and discovers the next-hop
signaling function (SF) in a peering relationship. The resource to Signaling Function (SF) in a peering relationship. The resource to
determine the SF of the target domain might be provided by a third- determine the SF of the target domain might be provided by a third
party as in the assisted-peering case. The following sections define party as in the assisted-peering case. The following sections define
mechanisms which may be used by the LRF. These are not in any mechanisms that may be used by the LRF. These are not in any
particular order and, importantly, not all of them have to be used. particular order and, importantly, not all of them have to be used.
6.1.2.1. DNS Resolution 6.1.2.1. DNS Resolution
The originating (or indirect) SSP uses the procedures in Section 4 of The Originating (or Indirect) SSP uses the procedures in Section 4 of
[RFC3263] to determine how to contact the receiving SSP. To [RFC3263] to determine how to contact the receiving SSP. To
summarize the [RFC3263] procedure: unless these are explicitly summarize the [RFC3263] procedure: unless these are explicitly
encoded in the target URI, a transport is chosen using NAPTR records, encoded in the target URI, a transport is chosen using NAPTR records,
a port is chosen using SRV records, and an address is chosen using A a port is chosen using SRV records, and an address is chosen using A
or AAAA records. or AAAA records.
When communicating with another SSP, entities compliant to this When communicating with another SSP, entities compliant to this
document should select a TLS-protected transport for communication document should select a TLS-protected transport for communication
from the originating (or indirect) SSP to the receiving SSP if from the Originating (or Indirect) SSP to the receiving SSP if
available, as described further in Section 6.2.1. available, as described further in Section 6.2.1.
6.1.2.2. Routing Table 6.1.2.2. Routing Table
If there are no End User ENUM records and the originating (or If there are no End User ENUM records and the Originating (or
indirect) SSP cannot discover the carrier-of-record or if the Indirect) SSP cannot discover the carrier-of-record or if the
originating (or indirect) SSP cannot reach the carrier-of-record via Originating (or Indirect) SSP cannot reach the carrier-of-record via
SIP peering, the originating (or indirect) SSP may deliver the call SIP peering, the Originating (or Indirect) SSP may deliver the call
to the PSTN or reject it. Note that the originating (or indirect) to the PSTN or reject it. Note that the Originating (or Indirect)
SSP may forward the call to another SSP for PSTN gateway termination SSP may forward the call to another SSP for PSTN gateway termination
by prior arrangement using the local SIP proxy routing table. by prior arrangement using the local SIP proxy routing table.
If so, the originating (or indirect) SSP rewrites the Request-URI to If so, the Originating (or Indirect) SSP rewrites the Request-URI to
address the gateway resource in the target SSP's domain and may address the gateway resource in the Target SSP's domain and may
forward the request on to that SSP using the procedures described in forward the request on to that SSP using the procedures described in
the remainder of these steps. the remainder of these steps.
6.1.2.3. LRF to LRF Routing 6.1.2.3. LRF to LRF Routing
Communications between the LRF of two interconnecting SSPs may use Communications between the LRF of two interconnecting SSPs may use
DNS or statically provisioned IP Addresses for reachability. Other DNS or statically provisioned IP addresses for reachability. Other
inputs to determine the path may be code-based routing, method-based inputs to determine the path may be code-based routing, method-based
routing, Time of day, least cost and/or source-based routing. routing, time of day, least cost and/or source-based routing.
6.1.3. The Signaling Path Border Element (SBE) 6.1.3. The Signaling Path Border Element (SBE)
The purpose of signaling function is to perform routing of SIP The purpose of the Signaling Function is to perform routing of SIP
messages as well as optionally implement security and policies on SIP messages as well as optionally implement security and policies on SIP
messages, and to assist in discovery/exchange of parameters to be messages and to assist in discovery/exchange of parameters to be used
used by the Media Function (MF). The signaling function performs the by the Media Function (MF). The Signaling Function performs the
routing of SIP messages. The SBE may be a B2BUA or it may act as a routing of SIP messages. The SBE may be a back-to-back user agent
SIP proxy. Optionally, an SF may perform additional functions such (B2BUA) or it may act as a SIP proxy. Optionally, an SF may perform
as Session Admission Control, SIP Denial of Service protection, SIP additional functions such as Session Admission Control, SIP Denial-
Topology Hiding, SIP header normalization, SIP security, privacy, and of-Service protection, SIP Topology Hiding, SIP header normalization,
encryption. The SF of an SBE can also process SDP payloads for media SIP security, privacy, and encryption. The SF of an SBE can also
information such as media type, bandwidth, and type of codec; then, process SDP payloads for media information such as media type,
communicate this information to the media function. bandwidth, and type of codec; then, communicate this information to
the media function.
6.1.3.1. Establishing a Trusted Relationship 6.1.3.1. Establishing a Trusted Relationship
Depending on the security needs and trust relationships between SSPs, Depending on the security needs and trust relationships between SSPs,
different security mechanisms can be used to establish SIP calls. different security mechanisms can be used to establish SIP calls.
These are discussed in the following subsections. These are discussed in the following subsections.
6.1.3.2. IPSec 6.1.3.2. IPsec
In certain deployments the use of IPSec between the signaling In certain deployments, the use of IPsec between the Signaling
functions of the originating and terminating domains can be used as a Functions of the originating and terminating domains can be used as a
security mechanism instead of TLS. However, such IPSec use should be security mechanism instead of TLS. However, such IPsec use should be
the subject of a future document as additional specification is the subject of a future document as additional specification is
necessary to use IPSec properly and effectively. necessary to use IPsec properly and effectively.
6.1.3.3. Co-Location 6.1.3.3. Co-Location
In this scenario the SFs are co-located in a physically secure In this scenario, the SFs are co-located in a physically secure
location and/or are members of a segregated network. In this case location and/or are members of a segregated network. In this case,
messages between the originating and terminating SSPs could be sent messages between the Originating and Terminating SSPs could be sent
as clear text (unencrypted). However, even in these semi-trusted co- as clear text (unencrypted). However, even in these semi-trusted co-
location facilities, other security or access control mechanisms may location facilities, other security or access control mechanisms may
be appropriate, such as IP access control lists or other mechanisms. be appropriate, such as IP access control lists or other mechanisms.
6.1.3.4. Sending the SIP Request 6.1.3.4. Sending the SIP Request
Once a trust relationship between the peers is established, the Once a trust relationship between the peers is established, the
originating (or indirect) SSP sends the request. Originating (or Indirect) SSP sends the request.
6.2. Target SSP Procedures 6.2. Target SSP Procedures
This section describes the Target SSP Procedures. This section describes the Target SSP Procedures.
6.2.1. TLS 6.2.1. TLS
The section defines the usage of TLS between two SSPs [RFC5246] The section defines the usage of TLS between two SSPs [RFC5246]
[RFC5746] [RFC5878]. When the receiving SSP receives a TLS client [RFC5746] [RFC5878]. When the receiving SSP receives a TLS client
hello, it responds with its certificate. The Target SSP certificate hello, it responds with its certificate. The Target SSP certificate
should be valid and rooted in a well-known certificate authority. should be valid and rooted in a well-known certificate authority.
The procedures to authenticate the SSP's originating domain are The procedures to authenticate the SSP's originating domain are
specified in [RFC5922]. specified in [RFC5922].
The SF of the Target SSP verifies that the Identity header is valid, The SF of the Target SSP verifies that the Identity header is valid,
corresponds to the message, corresponds to the Identity-Info header, corresponds to the message, corresponds to the Identity-Info header,
and that the domain in the From header corresponds to one of the and that the domain in the From header corresponds to one of the
domains in the TLS client certificate. domains in the TLS client certificate.
As noted above in Section 6.1.3.2, some deployments may utilize IPSec As noted above in Section 6.1.3.2, some deployments may utilize IPsec
rather than TLS. rather than TLS.
6.2.2. Receive SIP Requests 6.2.2. Receive SIP Requests
Once a trust relationship is established, the Target SSP is prepared Once a trust relationship is established, the Target SSP is prepared
to receive incoming SIP requests. For new requests (dialog forming to receive incoming SIP requests. For new requests (dialog forming
or not) the receiving SSP verifies if the target (request-URI) is a or not), the receiving SSP verifies if the target (Request-URI) is a
domain that for which it is responsible. For these requests, there domain for which it is responsible. For these requests, there should
should be no remaining Route header field values. For in-dialog be no remaining Route header field values. For in-dialog requests,
requests, the receiving SSP can verify that it corresponds to the the receiving SSP can verify that it corresponds to the top-most
top-most Route header field value. Route header field value.
The receiving SSP may reject incoming requests due to local policy. The receiving SSP may reject incoming requests due to local policy.
When a request is rejected because the originating (or indirect) SSP When a request is rejected because the Originating (or Indirect) SSP
is not authorized to peer, the receiving SSP should respond with a is not authorized to peer, the receiving SSP should respond with a
403 response with the reason phrase "Unsupported Peer". 403 response with the reason phrase "Unsupported Peer".
6.3. Data Path Border Element (DBE) 6.3. Data Path Border Element (DBE)
The purpose of the DBE [RFC5486] is to perform media related The purpose of the DBE [RFC5486] is to perform media-related
functions such as media transcoding and media security implementation functions such as media transcoding and media security implementation
between two SSPs. between two SSPs.
An example of this is to transform a voice payload from one codec An example of this is to transform a voice payload from one codec
(e.g., G.711) to another (e.g., EvRC). Additionally, the MF may (e.g., G.711) to another (e.g., EvRC). Additionally, the MF may
perform media relaying, media security [RFC3711], privacy, and perform media relaying, media security [RFC3711], privacy, and
encryption. encryption.
7. Address Space Considerations 7. Address Space Considerations
Peering must occur in a common IP address space, which is defined by Peering must occur in a common IP address space, which is defined by
the federation, which may be entirely on the public Internet, or some the federation, which may be entirely on the public Internet, or some
private address space [RFC1918]. The origination or termination private address space [RFC1918]. The origination or termination
networks may or may not entirely be in the same address space. If networks may or may not entirely be in the same address space. If
they are not, then a network address translation (NAT) or similar may they are not, then a Network Address Translation (NAT) or similar may
be needed before the signaling or media is presented correctly to the be needed before the signaling or media is presented correctly to the
federation. The only requirement is that all associated entities federation. The only requirement is that all associated entities
across the peering interface are reachable. across the peering interface are reachable.
8. Acknowledgments 8. Acknowledgments
The working group would like to thank John Elwell, Otmar Lendl, Rohan The working group would like to thank John Elwell, Otmar Lendl, Rohan
Mahy, Alexander Mayrhofer, Jim McEachern, Jean-Francois Mule, Mahy, Alexander Mayrhofer, Jim McEachern, Jean-Francois Mule,
Jonathan Rosenberg, and Dan Wing for their valuable contributions to Jonathan Rosenberg, and Dan Wing for their valuable contributions to
various versions of this document. various versions of this document.
9. IANA Considerations 9. Security Considerations
This memo includes no request to IANA.
10. Security Considerations
The level (or types) of security mechanisms implemented between The level (or types) of security mechanisms implemented between
peering providers is in practice dependent upon on the underlying peering providers is, in practice, dependent upon on the underlying
physical security of SSP connections. This means, as noted in physical security of SSP connections. This means, as noted in
Section 6.1.3.3, whether peering equipment is in a secure facility or Section 6.1.3.3, whether peering equipment is in a secure facility or
not may bear on other types of security mechanisms which may be not may bear on other types of security mechanisms that may be
appropriate. Thus, if two SSPs peered across public Internet links, appropriate. Thus, if two SSPs peered across public Internet links,
they are likely to use IPSec or TLS since the link between the two they are likely to use IPsec or TLS since the link between the two
domains should be considered untrusted. domains should be considered untrusted.
Many detailed and highly relevant security requirements for SPEERMINT Many detailed and highly relevant security requirements for SPEERMINT
have been documented in Section 5 of have been documented in Section 5 of [RFC6271]. As a result, that
[I-D.ietf-speermint-requirements]. As a result, that document should document should be considered required reading.
be considered required reading.
Additional and important security considerations have been documented Additional and important security considerations have been documented
separately in [I-D.ietf-speermint-voipthreats]. This document separately in [RFC6404]. This document describes the many relevant
describes the many relevant security threats to SPEERMINT, as well security threats to SPEERMINT, as well the relevant countermeasures
the relevant countermeasures and security protections which are and security protections that are recommended to combat any potential
recommended to combat any potential threats or other risks. This threats or other risks. This includes a wide range of detailed
includes a wide range of detailed threats in Section 2 of threats in Section 2 of [RFC6404]. It also includes key requirements
[I-D.ietf-speermint-voipthreats]. It also includes key requirements in Section 3.1 of [RFC6404], such as the requirement for the LUF and
in Section 3.1 of [I-D.ietf-speermint-voipthreats], such as the LRF to support mutual authentication for queries, among other
requirement for the LUF and LRF to support mutual authentication for requirements which are related to [RFC6271]. Section 3.2 of
queries, among other requirements which are related to [RFC6404] explains how to meet these security requirements, and then
[I-D.ietf-speermint-requirements]. Section 3.2 of Section 4 explores a wide range of suggested countermeasures.
[I-D.ietf-speermint-voipthreats] explains how to meet these security
requirements, and then Section 4 explores a wide range of suggested
countermeasures.
11. Contributors 10. Contributors
Mike Hammer Mike Hammer
Cisco Systems Cisco Systems
Herndon, VA
Herndon, VA - USA US
EMail: mhammer@cisco.com
Email: mhammer@cisco.com
--------------------------------------------------------------
Hadriel Kaplan Hadriel Kaplan
Acme Packet Acme Packet
Burlington, MA
Burlington, MA - USA US
EMail: hkaplan@acmepacket.com
Email: hkaplan@acmepacket.com
--------------------------------------------------------------
Sohel Khan, Ph.D. Sohel Khan, Ph.D.
Comcast Cable Comcast Cable
Philadelphia, PA
Philadelphia, PA - USA US
Email: sohel_khan@cable.comcast.com EMail: sohel_khan@cable.comcast.com
--------------------------------------------------------------
Reinaldo Penno Reinaldo Penno
Juniper Networks Juniper Networks
Sunnyvale, CA
Sunnyvale, CA - USA US
EMail: rpenno@juniper.net
Email: rpenno@juniper.net
--------------------------------------------------------------
David Schwartz David Schwartz
XConnect Global Networks XConnect Global Networks
Jerusalem
Jerusalem - Israel Israel
EMail: dschwartz@xconnnect.net
Email: dschwartz@xconnnect.net
--------------------------------------------------------------
Rich Shockey Rich Shockey
Shockey Consulting Shockey Consulting
US
USA EMail: Richard@shockey.us
Email: Richard@shockey.us
--------------------------------------------------------------
Adam Uzelac Adam Uzelac
Global Crossing Global Crossing
Rochester, NY
US
EMail: adam.uzelac@globalcrossing.com
Rochester, NY - USA 11. References
Email: adam.uzelac@globalcrossing.com
12. Change Log
NOTE TO RFC EDITOR: PLEASE REMOVE THIS SECTION PRIOR TO PUBLICATION.
o 19: Additional change to the IPSec section at Jari Arkko's
request.
o 18: Made several changes based on feedback from Adrian Farrel,
Bert Wijnen, Dan Romascanu, Avshalom Houri, Russ Housley, Sean
Turner, Tim Polk, and Russ Mundy during IESG review.
o 17: Misc. updates at the request of Gonzalo, the RAI AD, in order
to clear his review and move to the IESG. This included adding
terminology from RFC 5486 and expanding the document name.
o 16: Yes, one final outdated reference to fix.
o 15: Doh! Uploaded the wrong doc to create -14. Trying again. :-)
o 14: WGLC ended. Ran final nits check prior to sending proto to
the AD and sending the doc to the IESG. Found a few very minor
nits, such as capitalization and replacement of an obsoleted RFC,
which were corrected per nits tool recommendation. The -14 now
moves to the AD and the IESG.
o 13: Closed out all remaining tickets, resolved all editorial
notes.
o 12: Closed out several open issues. Properly XML-ized all
references. Updated contributors list.
o 11: Quick update to refresh the I-D since it expired, and cleaned
up some of the XML for references. A real revision is coming
soon.
13. References
13.1. Normative References
[I-D.ietf-speermint-requirements]
Mule, J., "Requirements for SIP-based Session Peering",
draft-ietf-speermint-requirements-10 (work in progress),
October 2010.
[I-D.ietf-speermint-voipthreats] 11.1. Normative References
Seedorf, J., Niccolini, S., Chen, E., and H. Scholz,
"Session Peering for Multimedia Interconnect (SPEERMINT)
Security Threats and Suggested Countermeasures",
draft-ietf-speermint-voipthreats-07 (work in progress),
January 2011.
[RFC1035] Mockapetris, P., "Domain names - implementation and [RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987. specification", STD 13, RFC 1035, November 1987.
[RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and [RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and
E. Lear, "Address Allocation for Private Internets", E. Lear, "Address Allocation for Private Internets",
BCP 5, RFC 1918, February 1996. BCP 5, RFC 1918, February 1996.
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
A., Peterson, J., Sparks, R., Handley, M., and E. A., Peterson, J., Sparks, R., Handley, M., and E.
skipping to change at page 17, line 25 skipping to change at page 14, line 39
June 2002. June 2002.
[RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation [RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation
Protocol (SIP): Locating SIP Servers", RFC 3263, Protocol (SIP): Locating SIP Servers", RFC 3263,
June 2002. June 2002.
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. [RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V.
Jacobson, "RTP: A Transport Protocol for Real-Time Jacobson, "RTP: A Transport Protocol for Real-Time
Applications", STD 64, RFC 3550, July 2003. Applications", STD 64, RFC 3550, July 2003.
[RFC3761] Faltstrom, P. and M. Mealling, "The E.164 to Uniform
Resource Identifiers (URI) Dynamic Delegation Discovery
System (DDDS) Application (ENUM)", RFC 3761, April 2004.
[RFC3764] Peterson, J., "enumservice registration for Session [RFC3764] Peterson, J., "enumservice registration for Session
Initiation Protocol (SIP) Addresses-of-Record", RFC 3764, Initiation Protocol (SIP) Addresses-of-Record", RFC 3764,
April 2004. April 2004.
[RFC3861] Peterson, J., "Address Resolution for Instant Messaging [RFC3861] Peterson, J., "Address Resolution for Instant Messaging
and Presence", RFC 3861, August 2004. and Presence", RFC 3861, August 2004.
[RFC3953] Peterson, J., "Telephone Number Mapping (ENUM) Service [RFC3953] Peterson, J., "Telephone Number Mapping (ENUM) Service
Registration for Presence Services", RFC 3953, Registration for Presence Services", RFC 3953,
January 2005. January 2005.
skipping to change at page 18, line 17 skipping to change at page 15, line 31
Protocol (SIP) Session Border Control (SBC) Deployments", Protocol (SIP) Session Border Control (SBC) Deployments",
RFC 5853, April 2010. RFC 5853, April 2010.
[RFC5878] Brown, M. and R. Housley, "Transport Layer Security (TLS) [RFC5878] Brown, M. and R. Housley, "Transport Layer Security (TLS)
Authorization Extensions", RFC 5878, May 2010. Authorization Extensions", RFC 5878, May 2010.
[RFC5922] Gurbani, V., Lawrence, S., and A. Jeffrey, "Domain [RFC5922] Gurbani, V., Lawrence, S., and A. Jeffrey, "Domain
Certificates in the Session Initiation Protocol (SIP)", Certificates in the Session Initiation Protocol (SIP)",
RFC 5922, June 2010. RFC 5922, June 2010.
13.2. Informative References [RFC6116] Bradner, S., Conroy, L., and K. Fujiwara, "The E.164 to
Uniform Resource Identifiers (URI) Dynamic Delegation
Discovery System (DDDS) Application (ENUM)", RFC 6116,
March 2011.
[I-D.ietf-speermint-voip-consolidated-usecases] [RFC6271] Mule, J-F., "Requirements for SIP-Based Session Peering",
Uzelac, A. and Y. Lee, "VoIP SIP Peering Use Cases", RFC 6271, June 2011.
draft-ietf-speermint-voip-consolidated-usecases-18 (work
in progress), April 2010. [RFC6404] Seedorf, J., Niccolini, S., Chen, E., and H. Scholz,
"Session PEERing for Multimedia INTerconnect (SPEERMINT)
Security Threats and Suggested Countermeasures", RFC 6404,
November 2011.
11.2. Informative References
[RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K. [RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
Norrman, "The Secure Real-time Transport Protocol (SRTP)", Norrman, "The Secure Real-time Transport Protocol (SRTP)",
RFC 3711, March 2004. RFC 3711, March 2004.
[RFC6405] Uzelac, A., Ed. and Y. Lee, Ed., "Voice over IP (VoIP) SIP
Peering Use Cases", RFC 6405, November 2011.
Authors' Addresses Authors' Addresses
Daryl Malas (editor) Daryl Malas (editor)
CableLabs CableLabs
Louisville, CO Louisville, CO
US US
Email: d.malas@cablelabs.com EMail: d.malas@cablelabs.com
Jason Livingood (editor) Jason Livingood (editor)
Comcast Comcast
Philadelphia, PA Philadelphia, PA
US US
Email: Jason_Livingood@cable.comcast.com EMail: Jason_Livingood@cable.comcast.com
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