Middleware/API and data fusion in Wireless Sensor Networks

This paper reviews the state of the art of two important aspects of Wireless Sensor Networks (WSNs), namely: 1. Models or Implementations of middleware and/or Application Programmers Interfaces (APIs) to abstract the inner workings of heterogeneous WSNs, and 2. Methods and techniques in reducing pervasive data generated by thousands or tens of thousands of sensor nodes within a WSN in order to reduce transmission load of individual sensor nodes and thereby, the energy consumption of the overall WSN. These two aspects of WSN are inter-related in that together they contribute to a unifying model of vastly heterogeneous WSNs composed of many sensor nodes. A unifying model for WSN will serve as a reference model based on which application specific WSNs can be designed using a universal API for ease of programming, and using a library of data fusion capabilities built into the API of the reference model.