All things related to multicast

[John Kristoff <>]

On Thu, 25 May 2006 13:03:39 -0400
Matthew Davy 
<>
 wrote:

> were quite opposed to this.     Passing 236/8 interdomain is no
> different than passing 10/8, both are IANA reserved addresses and,
> IMO, everyone should be filtering these at domain borders.

Well, it's a little different.  One just hasn't been assigned, the
other has been assigned for only private use, but I get your point.

> well.   We already do per-peer SA limiting.    We also have the  
> ability to do per-source SA limiting.    There was a thread on this  
> list a while back about implementing some per-source SA limits.
> My opinion is that limiting each source IP to some relatively large  
> number of different groups (say 1,000) on the backbone is a good  
> thing for the overall stability of multicast and wouldn't hinder any  
> legitimate use of multicast.    But, again, I think the consensus  
> that last time this was discussed was that the backbone shouldn't do  
> that type of limiting.    Is that still the consensus ?

The backbone shouldn't have to do that that kind of rate limiting,
but I think due to the nature of the swamp and what it can do to you,
it is worth considering.  Perhaps consensus might agree for you to
try it and if someone uncovers a problem, you'll agree to back it out.

> Also, in terms of Bill's and Cisco's lists being out of date, I'm  
> sure they are.    However, I think it's the most complete list out  
> there today.   If there are other groups that should be added, we'll  
> certainly consider adding them.

If you do the majority of the reserved addresses you'll cover most of
the common ones.  You'll have to play whack-a-mole with the remaining
ones that pop up.

John