Circular Joint Sink Mobility Scheme for Wireless Sensor Networks S. Rahim 1 , H. Rahim 1 , R. D. Khan 2 , M. Z. Siddiqi 1 , M. A. Qureshi 1 , U. Qasim 3 , Z. A. Khan 4 , S. Mahmood 1 , N. Javaid 1,* 1 COMSATS Institute of Information Technology, Islamabad, Pakistan 2 COMSATS Institute of Information Technology, Wah Cantt, Pakistan 3 University of Alberta, Alberta, Canada 4 CIS, Higher Colleges of Technology, Fujairah Campus, UAE * www.njavaid.com, nadeemjavaid@comsats.edu.pk, nadeem.javaid@univ-paris12.fr AbstractRegarding energy efciency in Wireless Sensor Networks (WSNs), routing protocols are engaged in a playful manner suggesting a consciousness of high value. In this research work, we present Circular Joint Sink Mobility (CJSM) scheme for WSNs. Our proposed scheme increases the stability period, network lifetime and throughput of the WSN. The beauty of our proposed scheme is that it controls the cluster head (CHs) election and selection in such a way that uniform load on CHs is ensured and it measures the distances through which each packet is sent from CHs to sink or Base Station (BS). Two mobile sinks are move in opposite direction, therefore each node or CHs calculates its distance and send data to the nearest one to preserve its energy. Thus, proposed scheme minimizes the overall energy consumption of the network. We implement CJSM scheme, in homogeneous, heterogeneous, reactive and proactive simulation environments. Results justify its applicability. Keywords: Throughput, Network Lifetime, Energy Efcient, Cluster Head I. I NTRODUCTION A computer network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections. The connections (network links) between nodes are established using either wired or wireless media. Network computer devices that originate, route and terminate the data are called network nodes[1]. Nodes can include hosts such as personal computers, phones, servers as well as networking hardware. A network packet is a formatted unit of data (a list of bits or bytes) carried by a packet-switched network. Network topology is the layout or organizational hierarchy of interconnected nodes of a computer network. Common layouts are bus network, star network, mesh, fully connected network and tree network. A WSN is a collection of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, pressure, and to cooperatively pass their data through the network to a main location. The WSN is built of nodes from a few to several hundreds or even thousands, where each node is connected to one (or sometimes several) sensors[2]. Each node has several parts including a radio transceiver with an internal antenna or connection to an external antenna, a microcontroller, an electronic circuit for interfacing with the sensors and an energy source, usu- ally a battery. The development of WSN was motivated by military applications such as battleeld surveillance. WSN are emerging as a new paradigm, consisting in the collection of information in a collaborative manner, where independent sensor nodes collect and share information. There are many next generation services that use this technology, since this type of networks has broad applicability. Today, such networks are used in many industrial and consumer applications, such as industrial process monitoring and control, machine health monitoring, and so on[3]. Size and cost constraints on sensor nodes result in corresponding constraints on resources such as energy, memory, computational speed and communications bandwidth. The topology of the WSNs can vary from a simple star network to an advanced multi-hop mesh network. The prop- agation technique between the hops of the network can be routing or !ooding[4], [5]. A wireless ad hoc network is a decentralized type of wireless network[6], [7]. The network is ad hoc because it does not rely on pre-existing infrastructure, such as routers in wired networks or access points in managed (infrastructure) wireless networks. Instead, each node partic- ipates in routing by forwarding data for other nodes, so the determination of which nodes forward data is made dynami- cally on the basis of network connectivity. However, the main challenges associated with these networks are node deploy- ment, network lifetime, scalability, power management, com- munication bandwidth[8], [9]. The latest research in WSNs deals with low power communications. Routing protocols play a key role for efcient energy consumption[10]. The need of a specic route with minimum energy cost necessitates the invention of new solutions. Earlier routing techniques, like Direct Communication (DC) and Minimum Transmission Energy (MTE)[11] are not energy-efcient. In DC, each node directly communicates with BS, whereas in MTE, each node communicates with its nearest neighbour. Farthest nodes are