Algorithms for resource utilization in sensor networks.

摘要

Wireless sensor networks are being envisioned for various civil, military and environmental monitoring applications. Since they are highly resource constrained, algorithms and protocols are designed to minimize resources. Minimizing the resources consumed for different protocols usually leads to degradation in the performance provided in terms of the application requirements. For mission critical applications, we sometimes need to provide guarantees even at the cost of extra overhead. Thus, efficient and intelligent use of resources rather than minimization of resource consumption should be the major focus in sensor network research. This is the primary theme of this thesis. We divide different protocols under two major categories, namely sensor data dissemination and network management and propose adaptive algorithms with the aim of maximizing resource utilization in sensor networks.; For the data dissemination problem, we show that providing different levels of assurances (reliability, latency etc.) in data delivery based on the information content in the sensed data is critical for proper utilization of resources. For the network management problem we consider two important functions: network state retrieval and topology control. We show that retrieving the network state at different levels of resolution and adaptively controlling the topology based on the current network conditions, application characteristics leads to a more prudent approach while conserving resources. I.e. we shift the algorithm design paradigm from an unconstrained optimization problem (the fixed schemes which aggressively minimize resource consumption) to optimization under application constraints. We propose adaptive algorithms for both the data dissemination and the network management problems which exploit the fundamental tradeoffs between resource consumption and protocol performance. The algorithms are not only more efficient in the resources they consume, but more importantly are also aware of the requirements of the applications they are designed for.