ABSTRACT
The current version of sensor nodes such as mica2 uses a 16-bit, 8-MHz Texas Instruments MSP430 microcontroller with only 10-KB RAM, 128-KB program space, 512-KB external flash memory to store measurement data, and is powered by two AA batteries [8]. Therefore, the energy impact of adding security features should be considered. For example, data authentication inTinyOS increases the consumed energy by almost 3%, while data authentication and encryption increases by 14% [9]. Furthermore, the processing capabilities in sensor nodes are generally not as powerful as those in the nodes of wired networks. Complex cryptographic algorithms are consequently impractical for WSNs. Not only do the resource limitations affect the WSN performance, but also the deployment nature does as well. Most WSNs are deployed in remote or hostile environments where nodes are exposed to physical attacks since anyone can access the deployment area and these sensors lack tamper-resistance property. The adversary can easily compromise one or more sensor nodes, extract secrets, and then affect the overall performance of the network. This attack is referred to as the node compromise attack and is sometimes referred to as the supervision attack or the physical attack [10,11].
