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New Member

multicasting

Hi all

if a switch is not multicast aware, if it recieves multicast traffic from a source, will it flood it out to all ports on the switch, like a broadcast ?

cheers

3 REPLIES

Re: multicasting

Yes. It will forward it out all ports.

New Member

Re: multicasting

but this is more like a broadcast right? where all pc's see the broadcast but only 1 will listen to it, is this the same for multicast but multiple pc's listen to it but the frame still gets flooded to all ports unless setup correctly via snooping ?

Bronze

Re: multicasting

Yes you are correct when you say that it is broadcast as Ethernet switch has no way to determine what ports the group members are on. As a result, the multicast traffic is forwarded to all ports except source port. So this is sort of business as usual for switch untill you configure it with IGMP snooping or CGMP in order to make it identify source and group member ports.

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