A DoS and fault-tolerant authentication protocol for group communications in ad hoc networks

In this paper, a novel authentication protocol is proposed, which satisfies both security and reliability requirements for group communications in ad hoc networks. The security features include identity anonymity and location intracability, periodic one-way session key and pseudonym identity refreshment with implicit authentication, dynamic joining and leaving an in-progress communication session, and data encryption. The reliability features include efficient Denial of Service tolerance for broadcasting refreshment messages, fault-tolerance for recovering lost refreshment messages, robustness for resisting the clock skews among member nodes and seamless key switch without disrupting ongoing data transmissions. The performance and security analysis show that the communication and computation overhead of the proposed protocol is similar to the existing one, while the security can be enhanced significantly. The simulation results demonstrate the robustness of the proposed protocol under severe Denial of Service attack and poor wireless channel quality.