"jf" == John Fraizer <nanog@EnterZone.Net> writes: If your switch is MCAST aware, you should be able to keep mcast traffic on ports tagged for it to begin with.
Is the idea that you can statically configure which of the IXP switch's ports should be multicast-capable at all? This would cause administrative overhead and would still not solve the problem of multicast-capable routers that receive copies of multicast traffic they aren't currently interested in.
If your switch isn't mcast aware. you need to find a new switch.
It is actually quite hard for switches to be "mcast aware" enough to copy multicast packets to exactly the set of who are interested in them. They either have to listen to and understand the multicast routing-protocol-of-the-day, or there must be some explicit protocol between multicast routers and the switch. In any case this is much more difficult than what most "multicast aware" switches currently do, i.e. IGMP snooping (which helps for end-systems, not routers, connected to the switch). -- Simon.