Distributed connectivity restoration in multichannel wireless sensor networks

Wireless sensor networks (WSNs) are widely used in various domains. However, the specificity of the nodes deployed in these networks makes them prone to failures. To overcome this problem and guarantee the continuity of the network functioning in the presence of node failures, fault tolerance mechanisms need to be designed and integrated to ensure the correct WSN operation. In addition to node failure, the interferences present a serious problem in WSNs. Such a problem is commonly solved by using multichannel communications. Thus, in this paper, we propose a distributed solution, called Connectivity Restoration for Multi-Channel WSNs (CR-MC), to recover from a connectivity loss for multichannel WSNs. The main task of this approach targets the restoration of the connectivity and the reassignment of the channels in a multichannel network after the failure of an articulation node whose failure leads to the network partitioning. CR-MC uses only the neighborhood information to execute the recovery and the channel reassignment tasks. On the other hand, if we consider multi-hop WSNs, a routing tree is generally constructed to disseminate the information to the sink node. Hence, the radio channels should be assigned with a great care to respect these network particularities. In this context, we propose a second solution, called Connectivity Restoration for Routing based Multi-Channel WSNs (CR-RMC) that exploits the routing tree as well as the vicinity information while allocating the channels. We compare the performance of the two proposed approaches CR-MC and CR-RMC by evaluating them through simulations.