Multicast VLAN Registration

In this section:

1. MVR Overview
   Internet Group Management Protocol (IGMP), which is used for IPv4 network multicasting, uses the resources inefficiently in Layer 2 networks. For example, a multicast stream received on one VLAN in a Layer 2 network is distributed to interfaces only within that VLAN, which could be a problem when receivers are in different VLANs. This inefficiency also poses the issue of duplication of multicast streams when hosts in multiple VLANs request the same multicast stream, which wastes the bandwidth. Multicast VLAN Registration (MVR) enables more efficient distribution of Internet Protocol Television (IPTV) multicast streams across a Layer 2 network. The duplication of multicast streams from the same source is eliminated while maintaining isolation between hosts on different VLANs.
2. Using MVR in a Multicast Television Application
   In a multicast television application, a PC or television with a set-top box can receive multicast streams. Multiple PCs or set-top boxes can be connected to one subscriber port, which is a switch port configured as an MVR receiver port (RP). When a subscriber selects a channel, the set-top box or PC sends an IGMP report to Switch A to join the appropriate multicast group. The switch modifies the forwarding table to include this receiver port as a forwarding destination in the MVLAN. An uplink port that sends and receives multicast data to and from within the MVLAN is called an MVR source port (SP).
3. Configuring Multicast VLAN Registration