A SCALABLE HIREARCHICAL CRYPTOGRAPHIC PROTOCOL FOR SECURE MULTICAST

Abstract

There has been a growing trend on supporting security service over internet. Probiding secutiry-enhanced multicast service for private conference could be even problematic due to that the network is full of nontrusted nodes, it is hard to achieve a safe registration procedure without incurring the implosion of confirmation messages, it is easy to trap into a wait deadlock when members performing peer validation, and the key distribution procedure is not scalable when distribution a single key to multiple members. In this paper, we identify these problems in each steps associated with providing the security-enhanced multicast service for private conferencing. We present a cryptographic protocol that employs core-based and source-based tree algorithms to construct a hierarchial tree amd several secutity mechanisms to provide authentication, integrity,and confidentiality services. The protocol uses a preauthorization scheme to construct trusted registrars in the multicast network to avoid incurring confirmation implosion, a decentralized validation procedure to prevent deadlock in peer-validation, cryptographic algorithms to keep message exchanges intact and confidential, and a hierarchically procedure to make key distribution scalable.