All things related to multicast

[Marshall Eubanks <>]

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