Patent ID: 6684331
Filing Date: 2004-01-27
Classification: H04L

Abstract:
A method for communicating a session key from a first node of a secure multicast group to a plurality of other nodes of the multicast group, wherein each of the nodes is represented by a leaf node of a binary tree stored in a domain of a directory service that is distributed across a wide area network, wherein each of the nodes is capable of establishing multicast communication and serving as a key distribution center, the method comprising the steps of:creating and storing a group session key associated with the multicast group and a private key associated with each node in a group; receiving information indicating that the first node is joining the multicast group; updating all affected keys of a subset of nodes in a branch of the binary tree that contains the joining node; receiving a new group session key for the multicast group, for use after addition of the first node, and a new private key for the first node, from a local group manager node; communicating a message to the subset of nodes that causes the subset of nodes to update their private keys.