ID-Based One Round Authenticated Tripartite Key Agreement Protocol with Pairings

With various applications of Weil pairing (Tate pairing) to cryptography, ID-based encryption schemes, digital signature schemes, blind signature scheme, two-party authenticated key agreement schemes, and tripartite key agreement scheme were proposed recently, all of them using bilinear pairing (Weil or Tate pairing). In this paper, we propose an ID-based one round authenticated tripartite key agreement protocol. The authenticity of the protocol is assured by a special signature scheme, so that messages carrying the information of two ephemeral keys can be broadcasted authenticly by an entity. Consequently, one instance of our protocol results in eight session keys for three entities. Security attributes of our protocol are presented, and the computational overhead and bandwidth of the broadcast messages are analyzed as well.