backbone
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... In situations where multiple multicast routers are connected to a
switched backbone, IGMP Snooping will not reduce multicast traffic ...
... network.
In switched backbone networks or exchange points, where predominantly
routers are connected with each other, a large amount of multicast
traffic ...
... topology should be customary when connecting routers to backbone
switches and thus not pose a limitation on the deployment ...
... o The same switch running RGMP in a backbone network will likely see
more states then running on the edge only doing IGMP ...