I wanted to make a number of video streams available across an IP WAN network, I have a couple of options. Unicast or Multicast. Unicast isn't the most efficient method necessarily so my preference would be Multicast.
Depends on the exact nature of what you are doing and the network(s) in question. Some things to think about: -Are you going to serve a mutlicast-aware audience directly? -Are you thinking of feeding another server(farm) to retransmit? Drawing from my own experiences, multicast is great for server-server distribution. It is (can be) fantastic for large audiences IFF you have a stable multicast-happy environment. IMHO multicast enivironments just require a bit more care-and-feeding. Multicast networks frequently need a strong human proponent too. Multicast is great but is counter-intuitive for most support staffs to handle. I have to be careful here because I could really get on a soapbox. Unicast is the lowest common denominator and is far easier to deal with in terms of transport peculularities. It is the only answer the makes sense for an on-demand enviroment. (I've known of groups to make scheduled multicast retransmissions, but you'd have to be pretty serious for this in terms of the human dynamic) -John