All things related to multicast

[Danny McPherson <>]

You didn't actually mention the topology here but assuming a sender-only 
source that's on a separate LAN than any of the group members, you definitely 
do need to be concerned with flooding on the source LAN.  You stated "I am 
also using Catalyst with cgmp or igmp
snooping" in your initial message.  Ideally, you'd want to use CGMP here so 
that the router would send a CGMP Join to the switch so that the switch will 
add the router port to the outgoing port list and stop flooding all ports.

> So, one of them will source and that sounds like no problem, but the other
> several will be sinks and need to join the tree, and they do not implement
> IGMP, so either I'm SOL or perhaps there's some static way to join them
> in?  Would that be an mroute?  At 15 Mbps I can not do this dense mode
> and can not broadcast this to all ports on my Catalyst switch.

You should be able to use the app Doug referred to on the receiver side and 
CGMP would still be more efficient than IGMP snooping..

-danny