All things related to multicast

[Bill Owens <>]

I had written a much longer note about the current state of interdomain IPv4 
multicast, from our vantage point, but. . . it doesn't really matter. 

The point, I believe, is that the critical period for widespread adoption of 
interdomain native multicast has passed. I don't think it matters to talk 
about IPv4 or IPv6; either way there are still considerable issues associated 
with building, maintaining and troubleshooting interdomain multicast 
connectivity. The only important difference is that IPv4 multicast seemed to 
have some promise, and by dint of great effort we were able to get some 
adoption in the R&E community. I don't see that happening with IPv6 
multicast. 

Even though the train has left the station there are still legitimate uses of 
IPv4 multicast; we aren't going to turn it off.  And when we start talking 
with IP equipment manufacturers in a month or two, trying to decide what 
could be the basis for an upgraded NYSERNet R&E network, I'm going to have 
requirements listed for IPv4/IPv6, unicast/multicast. But if a vendor comes 
to the top of the list with everything else that we want except interdomain 
IPv6 multicast, it won't stop us from buying their gear. . . and even if they 
do have excellent support, I'm not sure we'll turn it on.

Bill.