Stateless key distribution for secure intra and inter-group multicast in mobile wireless network

Group communication has become an important component in wireless networks. In this paper, we focus on the environments in which multiple groups coexist in the system, and both intra and inter-group multicast traffic must be protected by secret keys. We propose a mechanism that integrates polynomials with stateless secret updates to achieve personal key share distribution and efficient key refreshment during group changes. The proposed mechanism distributes keys via true broadcast. Compared to previous approaches, the proposed mechanism has the following advantages: (1) The adoption of symmetric encryption/decryption for multicast traffic matches the limited processing capability of wireless nodes. (2) The stateless feature of key distribution matches the properties of mobile wireless networks including frequent topology changes and temporary connection disruptions. (3) Special mechanisms are designed to reduce the communication overhead during key updates and provide protection against both intra and inter-group impersonation. The storage, computation, and communication overhead of the proposed mechanism is investigated. Analysis and simulation are conducted to demonstrate the improvements over previous approaches.