23 configuring mvr – CANOGA PERKINS CanogaOS Configuration Guide User Manual
Page 172
CanogaOS Configuration Guide
Proprietary & Confidential Canoga Perkins Metro Ethernet Switches
Page 172 of 350
23 Configuring MVR
Multicast VLAN Registration (MVR) is designed for applications using wide-scale deployment
of multicast traffic across an Ethernet ring-based service provider network (for example, the
broadcast of multiple television channels over a service-provider network). MVR allows a
subscriber on a port to subscribe and unsubscribe to a multicast stream on the network-wide
multicast VLAN. It allows the single multicast VLAN to be shared in the network while
subscribers remain in separate VLANs. MVR provides the ability to continuously send multicast
streams in the multicast VLAN, but to isolate the streams from the subscriber VLANs for
bandwidth and security reasons.
MVR assumes that subscriber ports subscribe and unsubscribe (join and leave) these multicast
streams by sending out IGMP join and leave messages. These messages can originate from an
IGMP version-2-compatible host with an Ethernet connection. Although MVR operates on the
underlying mechanism of IGMP snooping, the two features operation affect with each other. One
can be enabled or disabled with affecting the behavior of the other feature. If IGMP snooping
and MVR are both enabled, MVR reacts only to join and leave messages from multicast groups
configured under MVR. The switch CPU identifies the MVR IP multicast streams and their
associated MAC addresses in the switch forwarding table, intercepts the IGMP messages, and
modifies the forwarding table to include or remove the subscriber as a receiver of the multicast
stream, and the receivers must be in a different VLAN from the source. This forwarding
behavior selectively allows traffic to cross between different VLANs.
23.1.1 Terminology
MVR Multicast Vlan Registration
Source vlan The vlan for receiving multicast traffic for MVR
Source port The port in the source vlan for sending report or leave to upstream
Receiver port The port not in source vlan for receiving report or leave for
downstream