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Can a switch work with multicast without a router?

I have a 5505 switch with lost of users plugged into 24-port 10/100 blades. There is one vlan and no routing on this switch. Now I want to run a multicast app server on this switch and have several users participate. Do I need a router in order for the switch, with CGMP enabled, to block ports where there are no receivers?

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Re: Can a switch work with multicast without a router?

You dont need a router in this case....

2 REPLIES

Re: Can a switch work with multicast without a router?

You dont need a router in this case....

Re: Can a switch work with multicast without a router?

Without a multicast-enabled router conencted to the switch the Multicast traffic will be flooded to all ports within the VLAN. The Cat5000 Switch, whether it can understand IGMP or CGMP needs to know where the router is connected to be able to add a multicast CAM entry to the user ports that require the traffic.

Simply put the CGMP/IGMP router instructs the switch what user ports (MAC addresses) should receive the multicast traffic (this is done by the router multicasting the information to a 'well-know' multicast address). On receiving this information the switch programs its EARL table to forward the multicast traffic to the specific ports.

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