3Com S7902E, Руководство по настройке

Страница: 1084 / 2621

1-1
1
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 Volume .
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.