Subject: Re: MLDv1 still in the wild?

From: Jeroen Massar <[email-masked]>
Date: Mon, 05 Mar 2012 10:40:55 +0100

On 2012-02-29 23:10 , Stig Venaas wrote:
[..]
> I think the main reason OpenBSD and NetBSD don't support SSM is
> Apple's IPR claim. Without SSM support, there is little reason to
> support MLDv2.
> 
> I'm a bit curious about the reason for the question. At least MLDv2
> routers are supposed to support MLDv1 compatibility mode.

It was mostly curiosity as for ecmh on request I added the option to
disable MLDv1 handling completely, but I didn't recall anymore if there
was really an upshot to it, though it makes the code smaller a little bit.

>> However, RFC 5790, on Lightweight IGMP/MLD makes it easy to support
>> SSM. I think there is open source support for 5790 somewhere.
> 
> What it does is basically removing exclude mode for a non-empty
> source list. It is still a lot of work compared to IGMPv2/MLDv1.
> Apart from hosts in general, I can imagine a lot of special purpose
> devices that never needs SSM to only implement MLDv1.

MLDv1 is indeed quite easy, MLDv2 makes things a lot more complex, but
given a bit more testing I should have it all baked into sixxsd v4 and
then I finally can turn it on on all the SixXS PoPs instead of only a
select few of them.

Greets,
 Jeroen

---

From: Stig Venaas <[email-masked]>
Date: Mon, 05 Mar 2012 13:26:03 -0800

On 2/29/2012 2:10 PM, Stig Venaas wrote:
[...]
> Apple's IPR claim. Without SSM support, there is little reason to

I got some questions about this. See
http://www.ietf.org/ietf-ftp/IPR/APPLE-SSM.txt

See also e.g. http://marc.info/?l=snap-users&m=120819051424142

KAME did not add IGMPv3/MLDv2 to *BSD because of this. And as
a result Mac OS X did not have IGMPv3/MLDv2 until recently.
I'm not totally sure of the latter, but it is my understanding
the latest OS X has full support.

Stig

> Stig
>> Behcet
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