An Improved Authenticated Group Key Transfer Protocol Based on Secret Sharing

To achieve secure group communication, one-time session keys need to be shared among group members in a secure and authenticated manner. In this paper, we propose an improved authenticated key transfer protocol based on Shamir´s secret sharing. The proposed protocol achieves key confidentiality due to security of Shamir´s secret sharing and provides key authentication by broadcasting a single authentication message to all members. Furthermore, the proposed scheme resists against both insider and outsider attacks.