Resources Implications for Data Security in Wireless Sensor Network Nodes

Due to the sensitive nature of the data gathered by many wireless sensor networks it is becoming critical that this data be protected. The obvious way to secure this data is to encrypt it using a secure encryption algorithm before it is transmitted over the (open) air ways. However due to the constrained nature of the resources available on sensor nodes the cost, in terms of power consumption, speed and communications overhead, of any software based encryption procedure can often out weigh the risks of the transmission being intercepted. In this paper we present a solution to reduce this cost of employing encryption by taking advantage of a resource already available on many sensor nodes; this resource being the AES hardware encryption module available on the Chipcon CC2420 transceiver chip.

1. Introduction

Technological advancements in recent years have enabled the development of tiny, cheap, disposable and self contained battery powered computers, known as sensor nodes or “motes”, which can accept input from an attached sensor, process this input and transmit the results wirelessly to some interested device(s). When a number of these nodes work together, conceivably up to hundreds of thousands, a Wireless Sensor Network (WSN) is formed.