H3C S5500-EI - MSDP Support for Vpns; Protocols and Standards; MSDP Configuration Task List

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3.
RPs share the registered multicast information by means of SA messages. In this example, RP 1
creates an SA message and sends it to RP 2, with the multicast data from Source encapsulated in
the SA message. When the SA message reaches RP 2, RP 2 de-encapsulates the message.
4. Receivers receive the multicast data along the RPT and directly join the SPT rooted at the multicast
source. In this example, RP 2 forwards the multicast data down the RPT. When Receiver receives
the multicast data from Source, it directly joins the SPT rooted at Source.
The significance of Anycast RP is as follows:
• Optimal RP path—A multicast source registers with the nearest RP so that an SPT with the optimal
path is built. A receiver joins the nearest RP so that an RPT with the optimal path is built.
• Load balancing between RPs—Each RP maintains just part of the source/group information within
the PIM-SM domain and forward part of the multicast data, thereby achieving load balancing
between different RPs.
• Redundancy backup between RPs—When an RP fails, the multicast source that previously
registered with the RP or the receivers that previously joined the RP will register with or join another
nearest RP, thereby achieving redundancy backup between RPs.
MSDP support for VPNs
The interfaces on the multicast routers in a VPN can set up MSDP peering relationship between each
other. By exchanging SA messages between MSDP peers, multicast transmission in a VPN between
different PIM-SM domains can be implemented.
To support MSDP for VPNs, a multicast router that runs MSDP maintains an independent set of MSDP
mechanism for each VPN that it supports, including SA cache, peering connection, timers, sending
cache, and cache for exchanging PIM messages. The information in one VPN is isolated from another,
and MSDP and PIM-SM messages can be exchanged only within the same VPN.
Protocols and standards
• RFC 3618, Multicast Source Discovery Protocol (MSDP)
• RFC 3446, Anycast Rendezvous Point (RP) mechanism using Protocol Independent Multicast (PIM)
and Multicast Source Discovery Protocol (MSDP)
MSDP configuration task list
Task Remarks
Configuring basic MSDP
functions
Enabling MSDP Required
Creating an MSDP peer connection Required
Configuring a static RPF peer Optional
Configuring an MSDP peer
Configuring MSDP peer description Optional