An Improved Tripartite Authenticated Key Agreement Protocol from Pairings

Key agreement protocols are essential for secure communications in open and distributed environment. The study of tripartite key agreement has great theoretical and practical significance. Shim and Woo pointed out that the four tripartite authenticated key agreement protocols proposed by Al-Riyami and Paterson were insecure. Modifying the communication messages, an active adversary is able to calculate the session key. Therefore, we propose an improved TAK protocol (TAK-V) resisting all known active attacks. Finally, we analyze the security and computation efficiency.