METHOD FOR DISTRIBUTING A FILE THROUGH OVERLAY MULTICAST USING VIRTUAL SOURCE

摘要

A method for transmitting a file through multiple virtual source application layer multicast is provided to set virtual sources as well as parent nodes in members newly registered in a session, and to forward a file, thereby avoiding a control overhead and a packet overlay while the file is forwarded through application layer multicast. A member wanting to participate in a new session is disposed in a proper position of a tree, and requests an original source to participate in the session. The member is registered in a member list(100), and participates in the session. A packet is transmitted through the tree after the member participates in the session. Information on the member participating in the new session is on standby from the member, while the packet is first received. When the information is received, a virtual source candidate list is supplied to the member. The member sets portions of the virtual source candidate list to virtual sources, and receives data forwarded from the set virtual sources.