Network Aspects and Deployment in WSNs

Wireless sensor networks have been found to be very useful for many military and civil applications such as disaster management, surveillance of battle fields, and security. In many of these environments, the sensor nodes are strongly limited in terms of energy since their batteries usually cannot be recharged. Thus, designing energy-efficient algorithms has become an important factor to lengthen the lifetime of WSNs. Efficient network deployment and management is crucial to set an acceptable quality level in the network operation and to preserve as much of the node energy as possible. Correct energy management assures the desired performance level for data transmissions while lengthening the lifetime of the network. Energy restrictions combined with wide-scale deployments make implementing energy-saving methods necessary in most protocols, including the network and MAC layers. Energy-efficient routing can optimize the lifetime of the network by selecting paths that expend less energy, whereas collision suppression and decreasing energy consumption in the receiver must be the goals of the different Medium Access Control (MAC) mechanisms. Since energy considerations have dominated most of the investigations about WSN network operation and deployment, quality-of-service (QoS) issues such as latency, throughput, delay, or jitter have not been treated with great detail until now, topics that have been identified as interesting open issues for further research.