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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
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Chapter 41 Configuring MSDP Configuring MSDP
Figure 41-1 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 neve r 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 41-4
• Configuring a Default MSDP Peer, page 41-4 (required)
• Caching Source-Active State, page 41-6 (optional)
• Requesting Source Information from an MSDP Peer, page 41-8 (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