All things related to multicast

[Robert Olson <>]

At 01:33 PM 5/13/2002 -0700, John Zwiebel wrote:
> On Monday, May 13, 2002, at 01:02 PM, Robert Olson wrote:
>
> > If we could know that SSM was available on all sites' last-hop routers, 
> > and that all the OSs we use had support for IGMPv3 we'd be moving faster 
> > toward SSM (it has some nice properties we'd like to make use of...)
>
> IMHO, if it isn't, if you move to SSM, the folks that really want to play 
> with
> you will make sure that happens.  In the mean time, that shouldn't prevent
> you from being able to do both.  Moving to SSM means only:
>    -- including the source in the SDP information

But I may not know that. In an ad hoc conferencing application, I need 
additional infrastructure to keep track of senders so the address of a new 
sender can be distributed to everyone so they can join. It's quite 
convenient for the network to do this for me...



> in both cases, exactly what you are doing now.

Except that I don't have a way to distribute source IP address information 
at the moment..


> The movement to SSM -does-not- require a "flag day".  Nor does SSM
> require that you uses the 232/8 range.  If you are sending on an ASM
> multicast group (ie anything other than 232/8) if the application knows
> how to read the source info in the SDP message,


You're assuming I'm using an SDP message for coordination..

> and can send an
> IGMPv3 report, there is -nothing- preventing that last hop router from
> joining the shortest-path for that source.



> > Any news on support in L2 switches for IGMPv3 switching? How about Linux 
> > support for IGMPv3 (last I saw the sprint code isn't being supported).
> IGMPv3 snooping is easier to implement than IGMPv2 snooping. Vendors
> who haven't done so should be put out of business.

Okay, I'll have my network folks chase after Cisco and Intel.


> What does it take to get the sprint code "supported"?  Consumer demand.
> You're a consumer, tell your Linux vendor you want it or you won't buy it.
> OTOH, it isn't "supported" because no one is using it.  Taht circular 
> thing again.

Exactly. But I can't go out and require a service that my customers can't 
get...

--bob