METHOD AND APPARATUS FOR DISTRIBUTING AND UPDATING GROUP CONTROLLERS OVER A WIDE AREA NETWORK USING A TREE STRUCTURE

An approach for establishing secure multicast communication among multiple multicast proxy service nodes of domains of a replicated directory service that spans a wide area network. The domains are organized in a logical tree and each domain stores a logical tree that organizes the multicast proxy service nodes. Each domain also comprises a group manager at the root node of the binary tree, a multicast key distribution center, multicast service agent, and directory service agent and key distribution center (Unicast). Multicast proxy service nodes each store a group session key and a private key. Replication of the directory accomplishes distribution of keys. A Multicast group member joins or leaves the group by publishing a message. The local key distribution center and multicast service agent obtain the identity of the publisher from a local directory service agent. Based on the ID value, a secure channel is established with the DSA of the group member's domain. All keys of the binary tree branch that contains the joining or leaving node are updated, an updated group session key and a new private key are received.