Design and evaluation of energy efficient hierarchical energy tree based routing and exponential congestion control algorithms for wireless sensor networks

Abstract

The vision of ubiquitous computing requires the development of devices and technologies which can be pervasive without being intrusive. The basic components of such a smart environment will be small nodes with sensing and wireless communication capabilities, ability to organize flexibly into a network for data collection and delivery. Such networks are known as Wireless Sensor Networks (WSN). A Hierarchical Energy Tree (HET) is constructed based on the energy remaining in each sensor node by fixing the nodes in level 1 or level 2 of HET. The performance of the proposed algorithm is evaluated by constructing a WSN and implementing the Hierarchical Energy Tree based Routing Algorithm (HETRA) in ns2. This thesis work proposes a congestion control algorithm modifying the Additive Increase and Multiplicative Decrease (AIMD) rules, so as to be aggressive during packet drops and improve the throughput, which in turn improves the efficiency. The proposed algorithm is referred as Transmission Control Protocol/ Exponential algorithm (TCP/Exp). Simulation experiments are conducted initially to evaluate the performance of the proposed HETRA in WSN. This thesis has three major contributions, a routing algorithm for Wireless sensor Networks (Hierarchical Energy Tree based Routing Algorithm - HETRA), a Congestion control algorithm for WSN (Exponential Congestion Control Algorithm TCP/Exp) and Sensor Node Distribution Patterns for WSN. The performance of the combination is also evaluated with wireless topology interfaced to a wired Transmission Control Protocol/ Internet Protocol (TCP/IP) network through the base station node. The results again show that the combination HETRA, TCP/Exp and CROSS Pattern is the most energy efficient among the various combinations assumed for the simulation experiments newline