A Pairing Free Anonymous Certificateless Group Key Agreement Protocol for Dynamic Group

Group key agreement protocol is the primary requirement of several groupware applications like secure conferences; pay-per view, etc. which requires secure and authentic conversations among a group of participants via public networks. Protocols based on the certificateless public key cryptography (CL-PKC) are in demand because it overcomes the complex certificate management of traditional public key cryptography, as well as the key escrow problem of identity-based cryptography. Several group applications often need users anonymity also, along with their security features. However in current literature only few group key agreement protocols are available which supports user’s anonymity. Further almost all GKA protocols based on CL-PKC are employs bilinear pairing in their operations. The expensive computation of pairing motivates the researchers to propose pairing free protocols based on the CL-PKC. The present paper proposes a pairing free certificateless group key agreement protocol that meets the efficiency, authenticity, and strong security with complete anonymity. The formal security validation of proposed protocol has been done by using automated validation of internet security protocols and applications tool which shows that it is unforgeable against the various attacks. The proposed protocol has the comparable performance than other existing protocols in terms of computation and communication overheads.