A multi-layered architecture and protocols for large-scale wireless sensor networks

This paper studies the design of large-scale wireless sensor networks interconnecting several hundred sensor nodes. Given the low computation and battery power capacities of sensor nodes, the key design factors are scalability, energy efficiency and protocol simplicity. In this paper, we present a multi-level, multi-hop sensor network architecture for a network consisting of a few hundred nodes that communicate sensor data to a base-station. We present a unified framework that encompasses network organization, medium access control (MAC) and routing protocols. The MAC protocol, based on TDMA access, is designed to be collision-free, energy-efficient and fair. The routing protocol is multi-hop and uses a simple layered (tree-based) scheme. This reduces the number of control packets that need to be transmitted and hence reduces energy and computation costs. The performance of the network, in terms of delay, throughput, energy consumption and network lifetimes, is also studied in detail using discrete-event simulation.