Efficient Group Key Management for Non-reliable Link Networks

Abstract

Some multi communication networks don’t provide a reliable link for group key management, so as to implementing rekeying is failure frequently. To deal with the question, this paper presents a novel group key management scheme for non-reliable link networks, a ciphertext encrypted a secret shared key can be decrypted with any legitimate members whose scale is more than the threshold value, even if part of members’ links aren’t reliable. In rekeying process, each key fragment is divided into two parts with he shared production mechanism, so as to the member’s independent key fragments still keep unchanged, but imperative updated key belongs to the group manager. Therefore, in efficient aspect, the message and computation cost of rekeying is reduced, and the dependence of the reliable channel is reduced; in the security aspect, our proposed scheme can guarantee forward security and backward security, and secure against collusion attack even if the number of leaving member is more than the threshold value. Therefore, our proposed scheme is suitable to the non-reliable link networks.