Do i miss something

perhaps :-)

Please. Caching is _at least_ as efficient as multicasting (multicasting _is_ caching, with zero retention time) - w/o associated security and scalability problems.

Great, please do clue me in. I wasn't aware that you'd corrected all the issues with caching, and somehow defied physics wrt the process of "duplicate bits" on a wire not actually utilizing b/w.

Presenting L2/L3 multicasting as the best or the only or even a meaningful way to reduce transmission duplication is quite wrong.

I don't recall anyone doing that. They're both good ideas, they both need work.

A primary concern is the absense (and most likely, impossibility) of any L2/L3 multicast routing scheme capable of supporting any significant number of mcast trees.

Oh, and caching has no problems? I believe they're addressing two _slightly_ different problems.

Scalability on the Internet pretty much means that algorithms should run in O(log(N)**M) where N is the total number of end-points and M is constant. (Note that non-CIDR unicast routing doesn't fit this criterion, but CIDR does).

Perhaps O(log(N)**M) does apply to unicast, but the multicast model should differ. I'd agree that in an ideal state, sure, looks good, but...

The benefits of mining cheap cheese on the Moon are quite obvious. If you're willing to overlook the small fact that the Moon isn't made from cheese.

I'm with Brett, never been to the moon..

_No_ technological advances can help the fact that L2/L3 multicasts cannot be routed in a scalable fashion. Think what happens when there is 1mil multicast trees in the network.

and 10 billion caching servers won't give you even one extra bit to the end-user. -danny