Primitive Operations for Prioritized Data Reduction in Wireless Sensor Network Nodes

Wireless Sensor Networks have evolved into complex deployments where their nodes can have a full network protocol stack, database systems, etc. The main rationed resource in such a deployment is energy. Having power usage tightly managed ensures a long operational life for the node in cases where replenishments (either via recharge or battery change) are difficult or impossible. The basic deployment of Wireless Sensor Networks consists of sensing nodes as well as a relay node (i.e., sink) which collects sensory data to be relayed via a reliable network. The sink node can become unreachable due to malfunction, scheduled uptime or, in the case of mobile sink nodes, due to being out of the sensor nodespsila reach. In addition, the sensor nodes may decide against relaying data for some period. In these cases, optimal use of sensor node memory space also becomes critical. In this article, we classify data types and establish a set of node level approaches that can be taken to make the most of limited data storage via a prioritized data reduction. We conclude that such a methodology enables the node to be useful by collecting data beyond the point where its data storage size would otherwise allow.