Understanding of MSDP

Inter-Domain Multicast in MSDP

This section describes the principle and implementation mechanism of inter-domain multicast between MSDP peers.

Anycast RP in MSDP

This section describes the Anycast RP implementation process in a PIM-SM domain.

Multi-Instance MSDP

A VPN instance can support MSDP. To be specific, between the interfaces of the same instance on a multicast router (public network instance or VPN instance), the MSDP peer relationship can be set up, and then MSDP peers exchange Source Active (SA) messages to implement inter-domain VPN multicast.

MD5/Key-Chain Authentication

MSDP supports the Message-digest algorithm 5 (MD5) or Key-Chain authentication to enhance the security and reliability in MSDP message forwarding. The application scenario of the MD5/Key-Chain authentication is the same as that of basic MSDP applications.

RPF Rules of SA Messages

To prevent Source Active (SA) messages from being circularly forwarded between MSDP peers, MSDP performs the Reverse Path Forwarding (RPF) check on the received SA messages. MSDP strictly controls the inbound of the SA message. MSDP directly discards an SA message that does not comply with the RPF rules.