Polynomial construction and non-tree based efficient secure group key management scheme

Abstract

Designing an efficient key management scheme for secure group communication is challenging. We focus on non-tree based group key management scheme as they provide flexible and practical mechanism for collaborative computing. In this paper, we propose a non-tree based secure group key management scheme based on polynomial construction method. In the proposed scheme, an user is supposed to store only two keys (private shared key and group key). When a new user joins the group, only one encryption is required for rekeying and when an existing user leaves the group, only one polynomial construction is required for rekeying. The storage at the key distribution center is reduced in the proposed scheme. We analyze the security of the scheme and show that collusion of any subset of users cannot obtain the secret key of any noncolluded user. We compare the proposed scheme with the non-tree based schemes relying on polynomial construction method and show that the proposed scheme is efficient.