Secure group key management scheme for simultaneous multiple groups with overlapped memberships using binomial key tree with new approach to key distribution and key computation

In secure group communication model, key management is a challenging task. We propose a new approach for key distribution and key computation for the secure group key management based on polynomial interpolation method using binomial tree structure. The rich literature available for key management schemes for secure group communication focuses on operating only a single group. We focus on operation of simultaneous multiple groups with overlapping memberships. We design an efficient secure group key management scheme for simultaneous multiple groups with overlapping memberships. A new key structure called binomial key tree queue is proposed and new approach is used for key distribution and computation. The scheme scales well as the overlapping memberships across the multiple groups increases. The proposed scheme achieves significant reduction in rekeying and storage cost compared to two existing schemes in literature. Interestingly, efficiency in rekeying cost is achieved without much increase in storage at users.