Cross layer architectural approaches for Wireless Sensor Networks

A Wireless Sensor Network is a network of sensors that senses specified parameter(s) related to environment; processes data locally or in a distributed manner and wirelessly communicates information to central Base Station. The Base Station analyzes information and initiates suitable response if required. The complexities introduced by severely limited processing capabilities, memory and power supply in the sensor node at one end and the design needs of versatile applications at the other end have forced researchers to dissect the layered protocol design process. As a result cross layer approaches which attempt to exploit a richer interaction among communication layers to achieve performance gains have emerged. Cross-layer interactions offer the possibility of dealing with the special properties of Wireless Sensor Network that cannot be handled well by layered architectures. For example, this can be handling the variations in link quality or adjusting the radio strength, which influences the transmission range, the number of collisions, and energy consumption. These parameters can further be used as routing metrics at Network Layer for efficient routing. This paper surveys cross layer architectures, presents performance benchmarking for the architectures and finally compares them on the basis of the introduced benchmarks.