RFC 2022 (rfc2022) - Page 2 of 82

Support for Multicast over UNI 3

RFC 2022          Multicast over UNI 3.0/3.1 based ATM     November 1996


Table of Contents

   1. Introduction.................................................   4
    1.1 The Multicast Address Resolution Server (MARS).............   5
    1.2 The ATM level multicast Cluster............................   5
    1.3 Document overview..........................................   6
    1.4 Conventions................................................   7
   2. The IP multicast service model...............................   7
   3. UNI 3.0/3.1 support for intra-cluster multicasting...........   8
    3.1 VC meshes..................................................   9
    3.2 Multicast Servers..........................................   9
    3.3 Tradeoffs..................................................  10
    3.4 Interaction with local UNI 3.0/3.1 signalling entity.......  11
   4. Overview of the MARS.........................................  12
    4.1 Architecture...............................................  12
    4.2 Control message format.....................................  12
    4.3 Fixed header fields in MARS control messages...............  13
      4.3.1 Hardware type..........................................  14
      4.3.2 Protocol type..........................................  14
      4.3.3 Checksum...............................................  15
      4.3.4 Extensions Offset......................................  15
      4.3.5 Operation code.........................................  16
      4.3.6 Reserved...............................................  16
   5. Endpoint (MARS client) interface behaviour...................  16
    5.1 Transmit side behaviour....................................  17
      5.1.1 Retrieving Group Membership from the MARS..............  18
      5.1.2 MARS_REQUEST, MARS_MULTI, and MARS_NAK messages........  20
      5.1.3 Establishing the outgoing multipoint VC................  22
      5.1.4 Monitoring updates on ClusterControlVC.................  24
        5.1.4.1 Updating the active VCs............................  24
        5.1.4.2 Tracking the Cluster Sequence Number...............  25
      5.1.5 Revalidating a VC's leaf nodes.........................  26
        5.1.5.1 When leaf node drops itself........................  27
        5.1.5.2 When a jump is detected in the CSN.................  27
      5.1.6 'Migrating' the outgoing multipoint VC.................  27
    5.2. Receive side behaviour....................................  29
      5.2.1 Format of the MARS_JOIN and MARS_LEAVE Messages........  30
        5.2.1.1 Important IPv4 default values......................  32
      5.2.2 Retransmission of MARS_JOIN and MARS_LEAVE messages....  33
      5.2.3 Cluster member registration and deregistration.........  34
    5.3 Support for Layer 3 group management.......................  34
    5.4 Support for redundant/backup MARS entities.................  36
      5.4.1 First response to MARS problems........................  36
      5.4.2 Connecting to a backup MARS............................  37
      5.4.3 Dynamic backup lists, and soft redirects...............  37
    5.5 Data path LLC/SNAP encapsulations..........................  40
      5.5.1 Type #1 encapsulation..................................  40
      5.5.2 Type #2 encapsulation..................................  41



Armitage                    Standards Track