RFC 3353 IP Multicast in an MPLS Environment August 2002 Table of Contents 1. Introduction ............................................. 3 2. Layer 2 Characteristics .................................. 4 3. Taxonomy of IP Multicast Routing Protocols in the Context of MPLS ................................... 5 3.1. Aggregation .............................................. 5 3.2. Flood & Prune ............................................ 5 3.3. Source/Shared Trees ...................................... 6 3.4. Co-existence of Source and Shared Trees .................. 7 3.5. Uni/Bi-directional Shared Trees .......................... 10 3.6. Encapsulated Multicast Data .............................. 11 3.7. Loop-free-ness ........................................... 11 3.8. Mapping of Characteristics on Existing Protocols ......... 11 4. Mixed L2/L3 Forwarding in a Single Node .................. 12 5. Taxonomy of IP Multicast LSP Triggers .................... 14 5.1. Request Driven ........................................... 14 5.1.1. General .................................................. 14 5.1.2. Multicast Routing Messages ............................... 15 5.1.3. Resource Reservation Messages ............................ 15 5.2. Topology Driven .......................................... 16 5.3. Traffic Driven ........................................... 16 5.3.1. General .................................................. 16 5.3.2. An Implementation Example ................................ 17 5.4. Combinations of Triggers and Label Distribution Modes .... 18 6. Piggy-backing ............................................ 18 7. Explicit Routing ......................................... 20 8. QoS/CoS .................................................. 20 8.1. DiffServ ................................................. 20 8.2. IntServ and RSVP ......................................... 21 9. Multi-access Networks .................................... 21 10. More Issues .............................................. 22 10.1. TTL Field ................................................ 22 10.2. Independent vs. Ordered Label Distribution Control ....... 23 10.3. Conservative vs. Liberal Label Retention Mode ............ 24 10.4. Downstream vs. Upstream Label Allocation ................. 25 10.5. Explicit vs. Implicit Label Distribution ................. 25 11. Security Considerations .................................. 26 12. Acknowledgements ......................................... 26 Informative References........................................... 27 Authors' Addresses .............................................. 28 Full Copyright Statement ........................................ 30 Ooms, et al. Informational