H3C Technologies H3C S7500E Series Switches - Manual (Page 202)

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MSDP Configuration
When configuring MSDP, go to these sections for information you are interested in:
z MSDP Overview
z MSDP Configuration Task List
z Displaying and Maintaining MSDP
z MSDP Configuration Examples
z Troubleshooting MSDP
z The term “router” in this document refers to a router in a generic sense or a Layer 3 switch
running the MSDP protocol.
z For details about the concepts of designated router (DR), bootstrap router (BSR), candidate-BSR
(C-BSR), rendezvous point (RP), candidate RP (C-RP), shortest path tree (SPT) and rendezvous
point tree (RPT) mentioned in this manual, refer to PIM Configuration in the IP Multicast
Configuration Guide.
MSDP Overview
Introduction to MSDP
Multicast source discovery protocol (MSDP) is an inter-domain multicast solution developed to
address the interconnection of protocol independent multicast sparse mode (PIM-SM) domains. It is
used to discover multicast source information in other PIM-SM domains.
In the basic PIM-SM mode, a multicast source registers only with the RP in the local PIM-SM domain,
and the multicast source information of a domain is isolated from that of another domain. As a result,
the RP is aware of the source information only within the local domain and a multicast distribution tree
is built only within the local domain to deliver multicast data from a local multicast source to local
receivers. If there is a mechanism that allows RPs of different PIM-SM domains to share their
multicast source information, the local RP will be able to join multicast sources in other domains and
multicast data can be transmitted among different domains.
MSDP achieves this goal. With MSDP peer relationships established between appropriate routers in
the network, the RPs of different PIM-SM domains are interconnected with one another. Source active
(SA) messages are exchanged between these MSDP peers and thus the multicast source information
is shared among these different domains.