Relay Placement and Movement Control for Realization of Fault-Tolerant Ad Hoc Networks

Wireless communication is a critical component of battlefield networks. Nodes in a battlefield network exist in hostile environments and thus fault-tolerance against node and link failures is a desirable property for the communication topology of such networks. The network nodes are mobile and move depending on the objective they try to achieve; thus the topology needs to be re-established periodically. The transmitters used for communication have a fixed transmission range, so additional nodes are required for the construction of a fault-tolerant topology among network nodes. As the network nodes move, the additional nodes need to be moved as well; and it is desirable to move them a minimum amount to re-establish the topology as quickly as possible. We propose algorithms for minimizing the number of additional nodes required and the distance they need to move for construction of a topology with desired levels of fault-tolerance. We show via extensive simulations that the algorithms perform much better than an algorithm that does not take minimizing the movement of additional nodes into account.