| Sensor networks differ from general ad-hoc nets in many ways with respect to wireless communication in the sense that they are seriously constrained by local resources such as available energy, storage, reliability of each node. Sensor networks require wireless communication protocols that can extend the lifetime of the network and minimize energy consumption. Conventional protocols of direct transmission, multi-hop routing, and TDMA based protocols may not be suitable for sensor networks. The major design constraint in sensor networks is energy efficiency. All the conventional protocols are designed to increase bandwidth, quality of service, and to minimize end to end delay, thus are not optimal for sensor networks.; In this thesis, we propose a novel cluster-based architecture protocol to increase the life time of the sensor network. We implement our proposed scheme on NS-2 simulator as an extension to the LEACH [1] protocol. In this thesis, we targeted two factors of LEACH [1] protocol, which could improve the life time of the network. First, nodes send their data directly to the cluster head, and there is no way for non cluster head nodes to communicate if cluster head node dies. Tree-based clustering mechanism proposed in this thesis, attempts to overcome this problem. Second, cluster head nodes spend lot of energy in gathering data and in processing which could be redundant as well on many occasions because sensor networks are densely deployed and there is high probability that neighboring nodes sense and send same data to their cluster head. Data redundancy problem can be avoided by using eligibility criterion as proposed in this thesis.; We quantitatively compare LEACH [1] and the proposed protocol, based on parameters such as network life time, data sent. Our simulation results show that the proposed protocol can improve system lifetime, when compared to LEACH [1] and other general-purpose multi-hop approaches. |
