[c-nsp] Why does PIM enable IGMP?

[John Neiberger]

I know what they are for individually, but I was wondering why IGMP is
automatically enabled when PIM is enabled. My thought was that there
was no need for it on router-to-router links. I believe someone on
another forum gave the correct answer. Without IGMP, mtrace and mstat
would not work since those tools use IGMP packets.

On Mon, Feb 28, 2011 at 4:24 AM, Manu Chao <linux.yahoo at gmail.com> wrote:
> PIM is used in your Edge and Core network while IGMP is required at the Edge
> and Access
>
> On Wed, Feb 23, 2011 at 10:24 PM, John Neiberger <jneiberger at gmail.com>
> wrote:
>>
>> IGMP is enabled automatically when you enable PIM on an interface and
>> I can't figure out why. I've talked to a few other engineers and no
>> one can thing of why IGMP would need to be enabled on a
>> router-to-router connection running PIM. My only thought was that it
>> was a leftover from PIMv1, which used IGMP type 14 packets, but that's
>> a total guess.
>>
>> Do any of you happen to know the answer to this piece of trivia?
>>
>> Thanks!
>> John
>> _______________________________________________
>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>
>