All things related to multicast

["Ying Zhang" <>]

I've seen similar problem on Unix box running VLC. It sends IGMP V3 messages 
and didn't revert to V2, couldn't get SAP announcement. Just wondering if 
anyone saw this?
Ying
Network Engineer
Communication & Network Services,
Integrated Technology Services,
University of New Brunswick, Fredericton NB,
Canada E3B 5A3
Email: 

     Web: http://www.unbf.ca/its/
Phone:  (506) 447-3014     FAX:  (506) 453-3590
----- Original Message ----- 
From: "Bob Riddle" <>
To: "Marshall Eubanks" 
<>
Cc: "Nicholas J Humfrey" <>; "wg-multicast" 
<>
Sent: Thursday, July 05, 2007 2:26 PM
Subject: Re: VLC + Vista Multicast Issues


> FWIW - when Windows XP was first released, only IGMPv3 was supported - it 
> did not revert to IGMP v2.  I wrote a stupid program that would join a 
> specified mcast group that I would run on a Linux box that was on the same 
> switch as the WinXP machine.   I spent time emailing to Microsoft and 
> eventually they released a path and then a registry entry that could be 
> manipulated to allow the version of IGMP to be selected.  I might have 
> this stuff laying around somewhere if anyone thinks it matters.
>
> Marshall Eubanks wrote:
> > On Jul 5, 2007, at 11:17 AM, Nicholas J Humfrey wrote:
> >
> > > Yes, I wasn't expecting this behaviour, but it certainly seems to 
> > > happen. Could this be a known Cisco bug? Does it keep group membership 
> > > state in a single table or multiple tables for each IGMP version?
> > >
> > > nick.
> > >
> > > On 5 Jul 2007, at 15:54, Stig Venaas wrote:
> > >
> > > > Gary Parker wrote:
> > > > > On 5 Jul 2007, at 14:26, Nicholas J Humfrey wrote:
> > > > > > I find that these kinds of problems are the result of using a mixture 
> > > > > > of IGMPv2 and IGMPv3. Mac OS X uses IGMPv2, and I guess Vista should 
> > > > > > be using IGMPv3.
> > > > > Cheers Nick, that makes sense.
> > > >
> > > > It might be the reason, but it should/does not make sense. When an
> > > > IGMPv2 host sends IGMPv2 reports, the router should start doing IGMPv2
> > > > queries and the IGMPv3 host should fall back to using IGMPv2 for that
> > > > group as well. See section 7 of RFC 3376.
> >
> > This is correct. In case of a mix, the devices are suppose to revert to 
> > IGMP v2. As to when the Mac will
> > support IGMPv3, I have been trying...
> >
> > Regards
> > Marshall
> >
> > > > It would be good to investigate this further and find out what is
> > > > broken. This is supposed to work perfectly fine.
> > > >
> > > > Stig
> > > >
> > > > > > Btw; udp://@233.80.58.114:5000 is working fine here on my Mac! Is 
> > > > > > this a Freewire channel?
> > > > > Yes it is, Inuk multicast all their traffic over JANET and although 
> > > > > the video is only viewable with their client or a lot of fiddling 
> > > > > around with graphedit and DLLs in Windows the radio stations are all 
> > > > > plain MPEG2 audio and can be listened to quite happily in VLC. We have 
> > > > > a local SAP announcer on campus that lists all the Inuk radio streams 
> > > > > for the use of people who can't/won't use the Freewire client.
> > > > > Gary
>
> --
> Bob Riddle (bdr @ umich.edu)            Enabling Technologies
> University of Michigan Medical School   1301 Catherine Street
> M4101 MSB1 - 6024                       Ann Arbor, Michigan  48109-0624
>
> "Math illiteracy affects 7 out of every 5 people"