4000 Router Series IP Multicast Configuration Guide

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Figure 57 Multicast in multiple VPN instances

Through multicast VPN, when a multicast source in VPN A sends a multicast stream to a multicast group,

only the multicast group receivers in Site 1, Site 3, and Site 5 of VPN A can receive the multicast stream.

The stream is multicast in these sites and on the public network.

The prerequisites for implementing multicast VPN are as follows:

1. Within each site, multicast for a single VPN instance is supported.

2. On the public network, multicast for the public network is supported.

3. The PE devices support multiple VPN instances as follows:

{ Connecting with different sites through VPN instances and supporting multicast for each VPN

instance.

{ Connecting with the public network and supporting multicast for the public network.

{ Supporting information exchange and data conversion between the public network and VPNs.

The device implements multicast VPN by using the multicast domain (MD) method. This multicast VPN

implementation is referred to as MD-VPN.

The most significant advantage of MD-VPN is that it requires only the PE devices to support multiple VPN

instances. The MD-VPN solution is transparent to CE devices and P devices because multicast VPN can

be implemented without the need of upgrading CE devices and P devices or changing their original PIM

configurations.

MD-VPN overview

The basic MD-VPN concepts are described in Table 7.