TMS zl Management and Configuration Guide ST.1.0.090213

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Routing
Multicast
2. Select Multicast from the Show routes list.
The window displays all of the multicast routes that the module knows.
As you can see, multicast routes are different from unicast routes. Traffic
destined to a multicast address is usually destined to many different devices.
Therefore the TMS zl Module may need to copy a multicast packet and forward
it to several TMS VLANs. Therefore, instead of a gateway address, the route
lists VLANs.
In addition, multicast traffic often runs unidirectionally from a source to
receivers rather than bi-directionally as does unicast traffic. Multicast routes
can therefore be source-specific, and the source is indicated in the route.
The columns in the table are as follows:
■ Group Address — IP address of the multicast group
■ Source Address — IP address of the node that sends the multicast
■ Neighbor — IP address of the next-hop, upstream router in the multicast
group
■ VLAN—VLAN or VLANs that belong to the IGMP group