Optimal Routing and Clustering Technique for Wireless Sensor Networks Amine Rais, Khalid Bouragba, and Mohammed Ouzzif Laboratory RITM, ENSEM, Hassan II University of Casablanca, Casablanca, Morocco Email: amine.343@hotmail.fr; {bouragba2008, ouzzif}@gmail.com Abstract —Hierarchical routing protocols based on clustering involve a clustered organization of sensor nodes to enable data merge and aggregation. The CHs are responsible for retrieving data from the cluster's sensor nodes, and collecting the data received and sending them to the base station. These data are merged and aggregated at the CH level, which leads to significant energy savings. In order to improve the energy efficiency of this kind of routing, this article proposes a new protocol called Efficient Clustering Routing Protocol (ECRP). This protocol is based on the CLARANS algorithm, it takes into consideration the location and the energy level of the nodes to create uniform and balanced clusters with a CH located at the center of each cluster, which reduces data delivery duration to the CHs and minimizes energy consumption in the clusters. The simulations showed that our protocol outperforms the other hierarchical protocols in terms of the performance metrics. Index Terms—Wireless sensors networks, routing, clustering, CLARANS, energy efficiency, latency. I. INTRODUCTION The Hierarchical clustering of sensor nodes can greatly contribute to the overall scalability, lifespan, and energy efficiency of the WSN. Hierarchical routing is an effective way to reduce power consumption within the WSN [1], by aggregating and merging data captured in clusters to reduce the number of messages transmitted to the sink. It is particularly useful for applications that require scalability to hundreds or thousands of nodes. In this context, scalability involves balancing the load and using resources efficiently. Applications that require efficient aggregation of data are also candidates for clustering. In addition to supporting network scalability and reducing energy consumption through data aggregation, clustering has many other secondary benefits and related objectives [2]: it can determine the routing configuration in the clusters, and thus reduce the size of the routing table stored at each node. It can also preserve communication bandwidth because it limits the scope of inter-clusters interactions to the CHs, and avoids redundant message exchange between sensor nodes. In addition, clustering helps to stabilize the network topology at the sensor level, and reduce the maintenance cost of the topology. The sensors will only take care of Manuscript received February 20, 2019; revised August 8, 2019. doi:10.12720/jcm.14.9.758-764 the connection with their CH and will not be affected by the interactions between the CHs. The data transmission for long distance will result huge energy dissipation. The clustering protocol must have the capacity to minimize the energy required for transmitting the gathered data to the base station. The clustering methodology of the nodes is a major parameter in the design of hierarchical routing protocols. A cluster can effectively group various nodes, aggregate data, and reduce the energy dissipation of the nodes [3]. These clustering advantages lead us to develop a new clustering protocol based on the CLARANS [4] algorithm for partitioning the network and creating the clusters. This protocol must achieve the following objectives: balance the size of the clusters, minimize the distance between the nodes belonging to the same cluster, and reduce the distance between the member nodes and the CH. The rest of this paper is organized as follows. Section2 presents the related works. In section3 we present the radio model of communication. Section4 describes our protocol. The simulation and results are proposed in section5 and we conclude this paper in section 6. II. RELATED WORKS Heinzelmen et al. propose in [5] the LEACH protocol to divide the sensors of the network into two levels, they divide the sensors of the network into two levels: member nodes and cluster head nodes, LEACH uses the power of the received radio signal to create clusters, every sensor node decide autonomously to be cluster head node or a member node. The LEACH protocol is broken into rounds, every round is composed from 2 phases: set up phase and steady state phase. In the set up phase the clusters will be created, the sensor nodes selected as cluster heads broadcast an advertisement message to the rest of sensor nodes, which decide the cluster head to join for the current round, the nearest cluster head is selected based on the received signal strength of the advertisement. In the steady state phase the member nodes may communicate with their cluster head nodes using the TDMA schedule, a time slot is allocated for every sensor node to transmit data to the cluster head. The arbitrary selection of CHs in LEACH causes an unbalanced distribution of CH, dissipates the energy of the sensors and consequently reduces the lifetime of the network, for that a centralized version of LEACH named Journal of Communications Vol. 14, No. 9, September 2019 758 ©2019 Journal of Communications