All things related to multicast

[Bob Riddle <>]

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"