All things related to multicast

[Jon Zeeff <>]

I'd argue that MRTG doesn't show the short term packet loss caused by a ftp
session starting up and trying to use all the bandwidth that wreaks
havoc with video conferencing.

Broken things (like duplex mismatch) tend to cause lots of packet loss (ie, 
system is unusable until fixed).   The .5% packet loss problem seems
harder to cure.  Anybody have data on causes of most packet loss?


> I'm not prepared to agree that oversubscription causes the "vast majority" 
> of packet loss, especially in the R&E networks.  I've looked at the 
> MRTG/Cricket graphs of these networks and almost always see plenty of 
> headroom.  I agree with Marshall that there are a host of other problems 
> that crop up.
>
> I can't begin to count the number of times we find duplex mismatches, 
> dirty circuits (clock skew is my favorite), routers mis-configured to 
> handle multicast forwarding in software, IGMP brokenness, 5% of circuit 
> speed rate limits on multicast traffic (!!) and so on.