FLSS

Abstract

Topology control algorithms usually reduce the number of links in a wireless network, which in turn decreases the degree of connectivity. The resulting network topology is more susceptible to system faults such as node failures and departures. In this paper, we consider k-vertex connectivity of a wireless network. We first present a centralized algorithm, Fault-tolerant Global Spanning Subgraph (FGSSk), which preserves k-vertex connectivity. FGSSk is min-max optimal, i.e., FGSSk minimizes the maximum transmission power used in the network, among all algorithms that preserve k-vertex connectivity. Based on FGSSk, we propose a localized algorithm, Fault-tolerant Local Spanning Subgraph (FLSSk). It is proved that FLSSk preserves k-vertex connectivity while maintaining bi-directionality of the network, and FLSSk is min-max optimal among all strictly localized algorithms. We then relax several widely used assumptions for topology control to enhance the practicality of FGSSk and FLSSk. Simulation results show that FLSSk is more power-efficient than other existing distributed/localized topology control algorithms.