An Efficient Distributed Group Key Management Using Hierarchical Approach with Elliptic Curve Cryptography

Secure and reliable group communication is an active area of research. Its popularity is fuelled by the growing importance of group-oriented and collaborative properties. The central research challenge is secure and efficient group key management. In this paper, we propose an efficient many-to-many group key management protocol in distributed group communication. This protocol is based on Elliptic Curve Cryptography and decrease the key length while providing securities at the same level as that of other cryptosystems provides. The main issue in secure group communication is group dynamics and key management. A scalable secure group communication model ensures that whenever there is a membership change, a new group key is computed and distributed to the group members with minimal communication and computation cost. This paper explores the use of batching of group membership changes to reduce the time and key re-distribution operations. The features of ECC protocol are that, no keys are exchanged between existing members at join, and only one key, the group key, is delivered to remaining members at leave. In the security analysis, our proposed algorithm takes less time when users join or leave the group in comparison to existing one. In ECC, there is only 1 key generation and key encryption overhead at join and leave operation. At join the communication overhead is key size of a node and at leave operation is 2 log2 n -- 2 × key size of a node.