RE: 4941bis and multicast & QOS

"Manfredi (US), Albert E" <> Sun, 02 February 2020 20:36 UTC

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From: "Manfredi (US), Albert E" <>
To: Gyan Mishra <>, 6MAN <>
Subject: RE: 4941bis and multicast & QOS
Thread-Topic: 4941bis and multicast & QOS
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Date: Sun, 2 Feb 2020 20:36:14 +0000
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From: ipv6 <> On Behalf Of Gyan Mishra

> How would multicast ASM or SSM work with the privacy extension temporary address enabled.  With the privacy temporary address enabled the IGMP Join would go out the temporary addresses, just as would normal unicast traffic.

That's a good question, although only SSM would be a problem. In ASM, the IGMP/MLD join reports always go to the group multicast address anyway, and presumably, that won’t change. The unique source address of the client joining, or of the multicast source, should not matter. When responding to a new IGMP query, a new source address could be used in the report, still indicating to the router that membership exists. I would think, no problem.

In SSM, the IP destination address of the reports is a well-known multicast address, to routers, but of course, if you want to include only a certain set of sources, those source IP address(es) in the IGMP/MLD report either have to be valid, or you get nothing.

> The temporary address would be the  RPF path shared and SPT tree.

Isn’t this just related to multicast routing, between routers? Their addresses would not change at a dizzying rate?