Distributed Dynamic Fault-Tolerant Channel Allocation for Mobile Computing

E cient allocation of communication channels is critical for the performance of wireless mobile computing systems. The centralized channel allocation algorithms proposed in literature are neither robust, nor scalable. Distributed channel allocation schemes proposed in the past are complicated and require active participation of the mobile nodes. These algorithms are unable to dynamically adjust to spatial and temporal uctuations in channel demand (load). We present a distributed dynamic channel allocation algorithm in which heavily loaded regions are assigned a large number of communication channels, while their lightly loaded neighbors are assigned fewer channels. As the spatial distribution of channel demand changes with time, the spatial distribution of allocated channels adjusts accordingly. The algorithm described in this paper requires minimal involvement of the mobile nodes, thus conserving their limited energy supply. The algorithm is proved to be deadlock free, starvation free and fair. It prevents co-channel interference and can tolerate the failure of mobile as well as static nodes without any signi cant degradation in service. The algorithm is scalable and imposes low computation and communication overheads, as demonstrated by simulation experiments.