Signaling Transport (sigtran)

NOTE: This charter is a snapshot of the . It may now be out-of-date.

Last Modified: 2006-03-24

Chair(s):

Lyndon Ong <lyong@ciena.com>

Real-time Applications and Infrastructure Area Director(s):

Jon Peterson <jon.peterson@neustar.biz>
Cullen Jennings <fluffy@cisco.com>

* The Real-time Applications and Infrastructure Area Directors were seated during the IETF 65.

Real-time Applications and Infrastructure Area Advisor:

Cullen Jennings <fluffy@cisco.com>

Technical Advisor(s):

Shawn Routhier <sar@epilogue.com>

Mailing Lists:

General Discussion: sigtran@ietf.org
To Subscribe: sigtran-request@ietf.org
In Body: subscribe email_address
Archive: http://www.ietf.org/mail-archive/web/sigtran/index.html

Description of Working Group:

The primary purpose of this working group will be to address the
transport of packet-based PSTN signaling over IP Networks, taking into
account functional and performance requirements of the PSTN signaling.

For interworking with PSTN, IP networks will need to transport
signaling
such as Q.931 or SS7 ISUP messages between IP nodes such as a
Signaling
Gateway and Media Gateway Controller or Media Gateway.

Examples of such transport include:

  - transport of signaling between a Signaling Gateway and Media
Gateway
    or Media Gateway Controller
  - transport of signaling ("backhaul") from a Media Gateway to a Media
    Gateway Controller
  - transport of TCAP between a Signaling Gateway and other IP nodes

Applications include:

  - Internet dial-up remote access
  - IP telephony interworking with PSTN
  - Other services as identified


Specific goals are:

1. Architecture and Performance Requirements: The working group will
  produce an informational RFC identifying functionality and
  performance requirements to support signaling over IP. Signaling
  messages have very stringent loss and delay requirements in the
  existing telephone networks that need to be supported.

2- Transport: The working group will produce a standards track
  proposal or proposals defining transport of signaling protocols
  using SCTP, based on the requirements identified above.


These proposals will identify the method of encapsulation of different
signaling protocols.  This will include differentiating between
different protocols being carried, and what components are
transported,
translated or terminated at the SG.  Security and resilience must be
addressed.

Note: TCAP is a transaction protocol with different functions and
      requirements than call control signaling.  This will need to be
      taken into account in its mapping to IP networks.

      This work will be done in conjunction with other IETF working
      groups looking at similar issues.  The working group will also
      ensure that good information conduits exist with groups in other
      standards groups with expertise in the relevant signaling
      protocols or in the network requirements for the transport of
the
      relevant signaling protocols.

The group will make use of existing IETF QoS and security technology
and
will not address creation of new QoS or security functions for IP
networks. Nor will the working group work on defining new call control
or device control protocols.

Goals and Milestones:

Done  Submit Initial draft of Signaling Architecture and Performance Requirements document as an Internet-Draft
Done  Issue initial IDs on Transport Layer Protocols and Encapsulation of Signaling Protocols
Done  Submit requirements document to IESG for publication as an RFC
Done  Submit revised version of drafts incorporating discussions and early implementation experience.
Done  Submit IP-based transport protocol draft to IESG for publication as a Standards-track RFC
Done  Submit initial adaptation drafts to IESG for consideration as a Proposed Standard
Done  Submit protocol Applicability Statements draft to IESG for consideration as an Informationl RFC
Done  Submit protocol MIB draft to IESG for consideration as an Proposed Standard
Done  Submit security framework to IESG for consideration as Proposed Standard
Done  Resubmit updated IUA specification to IESG for consideration as proposed standard
Done  Submit remaining adaptation drafts to IESG for consideration as a Proposed Standard
Mar 2004  Submit implementation guidelines and other extensions based on testing to IESG for consideration as Proposed Standard

Internet-Drafts:

  • draft-ietf-sigtran-sua-implementor-guide-04.txt
  • draft-ietf-sigtran-rfc4233update-00.txt

    Request For Comments:

    RFCStatusTitle
    RFC2719 I Architectural Framework for Signaling Transport
    RFC2960 PS Stream Control Transmission Protocol
    RFC3057 PS ISDN Q.921-User Adaptation Layer
    RFC3257 I Stream Control Transmission Protocol Applicability Statement
    RFC3331 PS Signaling System 7 (SS7) Message Transfer Part (MTP)2 - User Adaption Layer
    RFC3332 PS SS7 MTP3-User Adaptation Layer (M3UA)
    RFC3788 Standard Security Considerations for SIGTRAN Protocols
    RFC3807 Standard V5.2-User Adaption Layer (V5UA)
    RFC3868 Standard Signalling Connection Control Part User Adaptation Layer (SUA)
    RFC3873 Standard Stream Control Transmission Protocol Management Information Base
    RFC4129 Standard Digital Private Network Signaling System (DPNSS)/Digital Access Signaling System 2 (DASS 2) Extensions to the IUA protocol
    RFC4165 Standard Signaling System 7 (SS7) Message Transfer Part 2 (MTP2) - User Peer-to-Peer Adaptation Layer (M2PA)
    RFC4166 I Telephony Signalling Transport over Stream Control Transmission Protocol (SCTP) Applicability
    RFC4233 Standard Integrated Services Digital Network (ISDN) Q.921-User Adaptation Layer
    RFC4666 PS Signaling System 7 (SS7) Message Transfer Part 3 (MTP3) - User Adaptation Layer (M3UA)