A survey of routing algorithms for wireless sensor networks

Abstract

Distributed wireless sensor networks consist of a large number of small, low-cost and low-power nodes (called motes) that coordinate with one another for environmental sensing. The sensor nodes are severely restricted in power, memory and computational resources. The nodes can be densely deployed in close proximity to the phenomenon to be observed. They can be deployed in hostile environments where the nodes may not be physically accessible and are subject to tampering. Nodes can be added to and deleted from the network at any time, resulting in unpredictable changes to the topology of the network. This presents new challenges in the design of routing protocols for sensor networks. In this paper, the constituent building blocks of sensor network routing protocols are identified and analyzed. The routing protocols are broadly classified into two categories: flat and hierarchical, and further into subcategories based on the centrality of their theme. Several routing algorithms belonging to each category that have been proposed in the literature are explored. The techniques used to achieve convergence and to eliminate routing loops are highlighted. Further the open problems in each algorithm are mentioned briefly. The paper concludes with a comprehensive comparison of the protocols based on several parameters.