RFC 2022 Multicast over UNI 3.0/3.1 based ATM November 1996 5.5.3 A Type #1 example...................................... 42 6. The MARS in greater detail................................... 42 6.1 Basic interface to Cluster members......................... 43 6.1.1 Response to MARS_REQUEST............................... 43 6.1.2 Response to MARS_JOIN and MARS_LEAVE................... 43 6.1.3 Generating MARS_REDIRECT_MAP........................... 45 6.1.4 Cluster Sequence Numbers............................... 45 6.2 MARS interface to Multicast Servers (MCSs)................. 46 6.2.1 MARS_REQUESTs for MCS supported groups................. 47 6.2.2 MARS_MSERV and MARS_UNSERV messages.................... 47 6.2.3 Registering a Multicast Server (MCS)................... 49 6.2.4 Modified response to MARS_JOIN and MARS_LEAVE.......... 49 6.2.5 Sequence numbers for ServerControlVC traffic........... 51 6.3 Why global sequence numbers?............................... 52 6.4 Redundant/Backup MARS Architectures........................ 52 7. How an MCS utilises a MARS................................... 53 7.1 Association with a particular Layer 3 group................ 53 7.2 Termination of incoming VCs................................ 54 7.3 Management of outgoing VC.................................. 54 7.4 Use of a backup MARS....................................... 54 8. Support for IP multicast routers............................. 54 8.1 Forwarding into a Cluster.................................. 55 8.2 Joining in 'promiscuous' mode.............................. 55 8.3 Forwarding across the cluster.............................. 56 8.4 Joining in 'semi-promiscous' mode.......................... 56 8.5 An alternative to IGMP Queries............................. 57 8.6 CMIs across multiple interfaces............................ 58 9. Multiprotocol applications of the MARS and MARS clients...... 59 10. Supplementary parameter processing.......................... 60 10.1 Interpreting the mar$extoff field......................... 60 10.2 The format of TLVs........................................ 60 10.3 Processing MARS messages with TLVs........................ 62 10.4 Initial set of TLV elements............................... 62 11. Key Decisions and open issues............................... 62 Security Considerations......................................... 65 Acknowledgments................................................. 65 Author's Address................................................ 65 References...................................................... 66 Appendix A. Hole punching algorithms............................ 67 Appendix B. Minimising the impact of IGMP in IPv4 environments.. 69 Appendix C. Further comments on 'Clusters'...................... 71 Appendix D. TLV list parsing algorithm.......................... 72 Appendix E. Summary of timer values............................. 73 Appendix F. Pseudo code for MARS operation...................... 74 Armitage Standards Track