Re: [v6ops] Interesting problems with using IPv6

Mikael Abrahamsson <swmike@swm.pp.se> Tue, 16 September 2014 05:16 UTC

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Date: Tue, 16 Sep 2014 07:16:41 +0200 (CEST)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Nick Hilliard <nick@foobar.org>
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Subject: Re: [v6ops] Interesting problems with using IPv6
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On Tue, 16 Sep 2014, Nick Hilliard wrote:

> - MLD is implemented to help l2 devices decide how and where to prune v6
> multicast transmission

Well, one could argue that MLD is there to tell the NIC what multicast 
packets to actually forward into the computer, and which ones are safe to 
drop on the floor at the NIC level. So one doesn't actually have to have 
L2 switches look at MLD and use it for forwarding decisions to actually 
get some benefit out of the multicast/broadcast distinction in IPv6.

So if bandwidth isn't a problem, but CPU IRQs are (they're usually not), 
then it's still a benefit. But I generally agree with your assessment of 
the situation, I just wanted to add this one point.

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se