World IPv6 Only Day.

Ray Soucy rps at
Thu Jun 9 17:34:25 UTC 2011

Cisco has had MLD snooping support for some time.  But they seem to
have broken it in a recent release, so it drops ND traffic and breaks
IPv6; been after them to fix it, but doesn't look like it's been
resolved yet.

But you're correct that without MLD snooping IPv6 ND traffic is on par
with IPv4 broadcast traffic and not a major problem.  It does mean,
however, that a large IPv6 multicast stream, like video or system
imaging, would be about as bad as doing so on IPv4 without IGMP

On Thu, Jun 9, 2011 at 12:49 PM, Iljitsch van Beijnum
<iljitsch at> wrote:
> On 9 jun 2011, at 6:36, Karl Auer wrote:
>> Well, a modern switch should work fine, even if not directly IPv6 aware,
>> but it won't understand multicast and will generally flood multicast
>> frames to all interfaces. So definitely stipulate IPv6 capability, even
>> for switches....
> Are there any switches out there that do MLDP snooping to avoid flooding IPv6 multicasts?

Ray Soucy

Epic Communications Specialist

Phone: +1 (207) 561-3526

Networkmaine, a Unit of the University of Maine System

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