A Rekeying Algorithms for Dynamics Multicast

To provide communication confidentiality in multicasting applications , traffic data in secure multicast is encrypted with a session key known only by certificated group members. Whenever there is a change in the group membership, the session key must be updated dynamically. The hierarchical key-tree approach can achieve logarithmic rekeying costs . However ,the efficient of hierarchical key-tree depends on whether the key tree remains balanced. In this paper, we propose to use an order-m B-tree as multicasting key management trees. the rekeying cost of inserting a new member is reduced compared to using the traditional hierarchical key-tree.