Something to keep in mind, multicast is an efficient method to forward one stream, for n recipients, between multicast routers. If the routers along the way are not doing true multicast routing or each end recipient has a unique path, you've loss one of the real advantages of multicast. One or both issues are often true when dealing with multicast on the Internet. If the traffic is very, very light, then a techology as proposed by the other poster (Satish's IPmc), multicast might logically simplify supporting an application.