multicast group traffic filtering

[Jon Webb <jon_webb@binary-one.com>]

Hi everyone,
I am trying to think of a way to handle a multicast test network. We 
have a setup that may require having a multicast router in a network 
that contains other multicast activity. This extra router would only 
want to route multicast traffic (control and data) for a specific 
multicast group (our test group), ignoring all other multicast traffic 
not part of that group. I know that the matching code is able to match 
on a multicast packet type, but I need to match on a specific group. I 
looked around the docs, but have been unable to find any kind of --match 
type support for multicast group ID's or some sort of IGMP connection 
tracking/handling. Is there something I missed? Can this be done with 
existing tools? Or else, could this be easily constructed?

Thanks,
Jon

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jon_webb@binary-one.com
jonwebb@soe.ucsc.edu
Computer Communications Research Group
University of California, Santa Cruz