Re: [BEHAVE] RE: [MBONED] FW: WGLC: draft-ietf-behave-multicast-06.txt

Manfredi, Albert E wrote:
>> -----Original Message-----
>> From: Brian Haberman [mailto:[email protected]] 
> 
>> The main issue being that on the upstream interface of the NAPT, the
>> same source address will be used for the Report and Done message.  So
>> depending on the order of those messages, traffic may stop temporarily
>> (until the router sends another Query).
> 
> Except that, I thought, the multicast router has to send group-specific
> or group-and-source-specific queries before it stops forwarding
> multicast packets, in IGMPv2 (the former only) and v3. This is supposed
> to ensure that there are no members left in the group, before the
> multicast router stops forwarding the packets.

That is true.  A conforming router would send a group-specific query
prior to changing its forwarding state.

> 
> So I'm not sure why there would be this gap in multicasts if everything
> is working as it should.
> 

I was using the basic model from the IGMP Proxy work where the inside
interface state is aggregated and the outside interface uses that
aggregate information within the context of the IGMP timers in use on
the external network.  That way, any gap in data forwarding would be
found in the proxy/NAPT device.

Regards,
Brian