RFC 2331 (rfc2331) - Page 2 of 26

ATM Signalling Support for IP over ATM - UNI Signalling 4

RFC 2331        IP over ATM Signalling - SIG 4.0 Update       April 1998


Table of Contents

   1.  Conventions ...............................................   2
   2.  Overview ..................................................   2
   3.  Use of Protocol Procedures ................................   3
       3.1  VC Teardown...........................................   3
   4.  Overview of Call Establishment Message Content ............   3
   5.  Description of Information Elements .......................   4
       5.1  ATM Adaptation Layer Parameters ......................   4
       5.2  Broadband Low Layer Information  .....................   5
       5.3  Traffic Management Issues and Related IEs.............   5
            5.3.1  ATM Traffic Descriptor ........................   6
                   5.3.1.1  Tagging vs. Dropping .................   7
            5.3.2  Traffic Parameter Negotiation ..................  7
            5.3.3  Broadband Bearer Capability ....................  8
            5.3.4  QoS Parameter ..................................  8
                   5.3.4.1  Signalling of Individual QoS Parameters  8
       5.4  ATM Addressing Information ...........................   9
   6.  ABR Signalling In More Detail  ............................   9
   7.  Frame Discard Capability ..................................  10
   8.  Security Considerations ...................................  10
   9.  Acknowledgements...........................................  10
   10. References ................................................  10
   11. Author's Address ..........................................  12
   Appendix A  Sample Signalling Messages ........................  13
   Appendix B  ABR and nrt-VBR Signalling Guidelines for IP Routers 15
   Appendix C  Combinations of Traffic Related Parameters ........  18
   Full Copyright Statement ......................................  26

1.  Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [BRA97].

2.  Overview

   UNI Signalling version 4.0 (SIG 4.0) is the ATM Forum follow-on
   specification to UNI 3.1 signalling (UNI 3.1). Among the new features
   in SIG 4.0, those of particular interest to IP over ATM environments
   are:

        o Available Bit Rate (ABR) Signalling for Point-to-Point Calls
        o Traffic Parameter Negotiation
        o Frame Discard Support
        o Leaf Initiated Join (LIJ) Capability
        o ATM Anycast Capability
        o Switched Virtual Path (VP) Service



Maher                       Standards Track