Adaptive Multicast Key Management for Tactical Networks

Secure and efficient multicast communication is an important area of research for tactical networks. Such forms of communication are essential for efficient collaborative planning, command and control, and situational awareness based applications. In order to realize secure group communication on the battlefield, secure multicast routing must be available and the necessary cryptographic keys must be distributed to the current group members. The routes must be maintained and the keys must be distributed, despite changes in network node position, network topology, communication channel performance, and other factors which affect network connectivity and performance. This paper presents an efficient algorithm, for secure group key management called one-way function chains extended (OFC/X). It is specifically designed for use in dynamic, mobile, ad hoc networks such as tactical networks. We present analytical results comparing the bandwidth performance of OFC/X with other multicast keying algorithms that have appeared in literature. We also compare the energy consumption of OFC/X during member deletion with these algorithms in ad hoc networks. We found that all other keying algorithms use at least 30 percent more energy than OFC/X and that the LKH algorithm, requires between 3 and 4 times the energy of OFC/X while using slightly over twice the bandwidth