Minimizing the energy dissipated by wireless sensor nodes

‘Weighted Route Selection in Cluster-Based Protocol for Wireless Sensor Networks’ by Rivo S.A. Randriatsiferana, Herimpitia T.C. Antilahy, Frederic Alicalapa and Richard Lorion
EUDL‘s Most Downloaded Paper for the month of July (2016), appears in Issue #8 of EAI Endorsed Transactions on Future Internet

Technological advancements have come a long way over the decades. Mutual communication between various devices and appliances that we use is nothing unheard of. In fact, humanity has already entered an era of technological convergence, where objects of our every-day life communicate through a network of heterogeneous networks. The basic premise for such evolution is the development of wireless network sensors (WSN). These sensors consist of a set of nodes which communicate with each other over wireless links. For them to function properly, it is essential to mitigate several constraints such as energy consumption and data communication. Since the nodes are small components with limited resources, the most crucial challenge remains to control the energy consumption in order to maximize a network lifetime. Authors of this paper have proposed various protocols to tackle this issue. Among them, the Weighted Route Selection in Cluster-Based Protocol or WeRoS in short, came up as the most efficient protocol, both in terms of energy consumption and extension of the network lifetime.

Generally, WSNs are required to work without human intervention and supervision. This means organizing network into a connected hierarchy — load balancing, thus increasing the network lifetime. To ensure an effective load balance between nodes,  some of them are sometimes elected as leader, which are usually called cluster-heads (CHs). The selection of CHs plays a major role in what is known as clustering process. This process is divided into two main phases:  the cluster construction phase and the data communication phase. There are two possibilities that can be used for the data communication process: one-hop and multi-hop communications.

WeRoS, as proposed by the authors, combined the CH selection rotation and a multi-hop communication for data forwarding and balancing the energy consumption between nodes. The CH selection depends on the remaining energy of the nodes and its coefficient of variation. These parameters are introduced to elect CHs by maximizing the remaining energy as well as minimizing its variance. Furthermore, multi-hop communications generally route data using fixed paths, overusing the nodes closest to Base Station (BS), thus making the signal diminish quickly which results in the existence of energy holes. WeRoS tackled this issue with an algorithm named  “Binary Greedy Forwarding”. It consists of designing an adjacency table between CHs in order to establish communication between CHs and BS which allows for CHs to become self-organized during the data transmission phase. The data is then routed to the BS via an unique path, effectively addressing the energy hole problem.

The authors have demonstrated the superiority of WeRoS via a series of simulation experiments. They compared it with other protocols such as LEACH, LEACH-C, e-LEACH and HEED. These simulations show, that WeRoS exhibits satisfactory comparative performances on energy consumption reduction, nodes synchronous death, and increases the overall network lifetime.

In order to read about the study in greater detail, you can download the full paper on EUDL.