Review on Improved Fault Tolerance in WSAN with Minimal Topology Changes

Perraju P. Tetali and Garima Singh

In wireless sensor-actor networks, sensors review their surroundings and forward their data to actor nodes. Actors collectively respond to achieve predefined application mission. Since actors have to coordinate their operation, it is necessary to maintain a strongly connected network topology at all times. Moreover, the length of the inter-actor communication paths may be constrained to meet latency requirements. However, a failure of an actor may cause the network to partition into disjoint blocks and would, thus, violate such a connectivity goal. One of the effective recovery methodologies is to autonomously reposition a subset of the actor nodes to restore connectivity. Contemporary recovery schemes either impose high node relocation overhead or extend some of the inter-actor data paths. This paper overcomes these shortcomings and presents a Least-Disruptive Topology Repair (LDTR) algorithm. LDTR relies on the local view of a node about the network to devise a recovery plan that relocates the least number of nodes and ensures that no path between any pair of nodes is extended. LDTR is a localized and distributed algorithm that leverages existing route discovery activities in the network and imposes no additional prefailure communication overhead. The performance of LDTR is analyzed mathematically and validated via extensive simulation experiments.

©2015 International Journal of Computer Science and Applications 

Published by Research Publications, India