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Catalyst 3560 Switch Software Configuration Guide
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Chapter 45 Configuring MSDP
Configuring MSDP
Figure 45-1 MSDP Running Between RP Peers

MSDP Benefits

MSDP has these benefits:
It breaks up the shared multicast distribution tree. You can make the shared tree local to your
domain. Your local members join the local tree, and join messages for the shared tree never need to
leave your domain.
PIM sparse-mode domains can rely only on their own RPs, decreasing reliance on RPs in another
domain. This increases security because you can prevent your sources from being known outside
your domain.
Domains with only receivers can receive data without globally advertising group membership.
Global source multicast routing table state is not required, saving memory.
Configuring MSDP
These sections contain this configuration information:
Default MSDP Configuration, page 45-4
Configuring a Default MSDP Peer, page 45-4 (required)
Caching Source-Active State, page 45-6 (optional)
Requesting Source Information from an MSDP Peer, page 45-8 (optional)
MSDP peer
RP + MSDP peer
49885
Receiver
MSDP peer
MSDP SA
MSDP SA
MSDP SA
TCP connection
BGP
Source
Multicast
Register
Peer RPF flooding
PIM sparse-mode
domain
PIM
DR
(S,G) Join