Boundary Node Selection Algorithms by Simple Geometrical Properties in WSNs

Catastrophic events in wireless sensor networks can result in large holes in network coverage. Repair of such damage requires accurate identification of the proper subset of nodes which form the boundary of the damaged region, such that some of these nodes -- the so-called outer boundary nodes - may be directed to reduce the size of the damaged region by either increasing sensing and transmission power or physically moving closer to the centre of the damaged region. Decisions as to whether a particular node should participate in the recovery process can made autonomously based on limited local information available to a node and its immediate neighbors. This paper proposes a number of algorithms which nodes may use to determine whether or not they belong to the set of outer boundary nodes. Simulation results are presented which compare the efficacy of each algorithm using a number of metrics.