Deploying yet another box around the edge is expensive in terms of capital, support and maintenance, particularly depending upon the size of one's network edge. Ideally, multicast provides this at no additional cost excepting the engineering resources involved. We (Worldcom vBNS) see virtually no demand for mbone content or other interdomain multicast. However we are seeing a good deal of interest from customers interested in high bandwidth intradomain multicast (often as a replacement for satellite delivery). For example, we are supporting multiple HDTV multicast streams (~20Mbps each) for customers today. I am not sure that caches are an appropriate solution in this case. rob On Mon, Jun 11, 2001 at 12:43:19AM -0700, Sean Donelan wrote:

Folks have given a number of interesting multimedia applications using multicast, but I'm not sure any of them really need multicast.

Akamia/iBeam/Skycache, or any other set of large memory buffer boxes around the network edge, seem to be a much better way to replicate multimedia streams, and even provide the popular VCR start/pause/stop effect. This works well for single sourced (or limited source) multimedia streams that have very little interaction with the recipient (aka TV for the Internet).

Multicast seems to be more efficient for updating large buffer edge boxes than delivering the content directly to the end-user.