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routing multicast

I need to transfer multicast packets (three of four ip multicast addresses) from one LAN to another LAN. What is the most simple configuration to achieve that?

I have one or two routers between both LAN's.


Community Member

Re: routing multicast

If you want to know the simplest way is to enable multicast routing is that it only takes two commands on each router. 1) enable multicast routing(ip multicast-routing) in global configuration. 2) then use PIM as a multicast protocol with "ip pim dense-mode" on the interface. basically its the interfaces that will cooperate in the multicast process and multicasting will work. that is the simplest way. but by default switches will flood the multicast packets to every port. if you don't want the switch to flood all its port you need to enable CGMP. you would need to enable that on the interface of the router with "IP CGMP" and then enable CGMP on the switch itself too. that if the switch supports it. but if you want to look into it more look on cco. here is the link

basically dense-mode is a flood and prune princepal. so basically the source will send out the multicast packets to all dense enabled interfaces and if the router will query via IGMP to its segment. if it don't get a query back then it sends a prune message to its upstream stream(towards the source). but this is done every 3 minutes. so i gave you the easiest way to get multicast working.

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