Research On Zone Based Routing For Wireless Sensor Networks

Wireless Sensor Networks(WSNs)are used to monitor and gather data from accessible as well as inaccessible terrains.Generally,each of its constituent node senses the data from its surrounding and sends it to the base station(BS).The mushroom growth of sensor networks is resulting in increased functionality and decreased implementation cost.The downside is,however,the limited available energy possessed by the sensor nodes,since it is usually infeasible to replace or recharge the node battery due to the involved cost and/or geographic reasons.Besides energy,there are challenges,like restricted memory and processing power,short range communication,scalability and deployment in hostile environments.Major culprits in the consumption of energy are the processor and radio at the node.Different layers of the protocol stack may contribute variably to energy consumption but we believe that the primary focus should be the network layer,as efficient routing can minimize processor as well as radio energy consumption.For instance,reducing the number of messages and control traffic should economize the energy consumed in processing on one hand and the energy consumed in transmission and reception on the other hand.Researchers have developed a lot of energy efficient routing protocols but they could not limit the control information that is being needed for discovering neighbors,finding energy efficient and shortest routes,reliability and path maintenance before every new round of data communication begins,which ultimately reduces the network lifetime.Optimizing such control information in the network greatly enhances the network lifetime and throughput.We have targeted zone based routing(ZBR)for sensor network in our research to cater the said challenges.Generally in multihop routing,utmost energy level nodes,located closer to BS are selected for routing purpose.In contrast to this,ZBR mostly utilizes multi-hop dynamic flooding routing protocol that are not energy efficient solutions.According to literature some work has also been investigated in ZBR where the next relaying node along the routing path is selected randomly without considering the node energy and its location,which is ultimately not an energy efficient and optimum routing scheme for low power sensor networks.Moreover in ZBR,the redundant/unwanted data traffic is also generated and receipted at BS which greatly affects the overall network performance.Removing such unwanted data traffic from the network greatly improves the performance in terms of network lifetime and throughput.The main motivation behind this study is to develop a new ZBR strategy for low power WSNs which should be light-weight,energy efficient,completely stateless and does location based routing without the needs for the nodes to know their respective position while acquiring negligible control information during the routing process.Moreover it might ensure the only one copy of each message receipted at BS and removes the probability of unwanted data traffic from the network.Our main contributions are summarized as below:1.We developed a routing algorithm using the ring-zone(RARZ)model.The protocol takes routing decisions based on the remaining energy of nodes and performs location-based routing without the need for the nodes to know their respective positions without incurring any control overhead in the routing process.The protocol partitions the network into concentric rings/zones around the BS.Each node assigns itself to a particular zone known by a ringID/zoneID.Multi-hop routing is performed and nodes within inner zones carry data for the outer zones towards the BS.Routing decisions are taken on fly without having any prior information about the immediate neighbors and other topological information of the network.2.It is generally seen in the ZBR that multiple copies of the same packets transmitted in the network.To overcome the issue we have developed EEHRT(Energy efficient technique for handling redundant traffic)that controls the redundant traffic by introducing short beacon message in the ZBR routing.EEHRT also limit the control traffic by acknowledging the source node using wireless broadcast advantage(WBA)without sending any special acknowledgement packet to the sender,which also increment the network lifetime.3.In sensor networks hierarchical routing is considered the most energy efficient and extended network life time technique due to less number of transmission in the network.On the other hand ZBR claims less routing control overhead to show the overall network life time to be extended.However to assess the effectiveness of between the two main categories of routing,we have conducted a simulation based comparison of ZBR and hierarchical routing with static clustering scheme.Simulation results show that ZBR outperforms hierarchical routing with static clustering in terms of energy efficiency,network lifetime and throughput.