Multicast Hot Backup
Hot backup is deployed among two NE20Es, and multicast hot backup is deployed on the two NE20Es at the same time. Two NE20Es serve as DRs. The network-side interfaces of the DRs are configured with Protocol Independent Multicast (PIM), and the user-side interfaces of the DRs are configured to terminate the Internet Group Management Protocol (IGMP) messages of STBs.
On this network, HSI, VoIP, and IPTV services can be protected.
As shown in Figure 8-26, the NE20Es serve as multicast replication points. Multicast hot backup does not apply to VLAN-based or interface-based multicast replication.