Investigating and Analyzing the Light-weight ciphers for Wireless Sensor Networks

The Wireless Sensor Networks (WSNs) are characterized by the severe constraints in the computational, storage and energy resources. Though there has been significant improvement in the available computational resources due to the proliferation of the next-generation sensor nodes, the energy and storage resources of sensor nodes are still limited. As the sensor nodes are often deployed in ubiquitous and pervasive environments, it is necessary to ensure communications security in a WSN. However, the use of the security protocols adds to the associated overhead. Therefore, ensuring communications security in a WSN is a challenge. We believe that since the core component of any security protocol is the cipher used therein; the overhead due to a security protocol can be largely reduced, by employing essentially a lightweight cipher. But at the same time, the cipher so employed must ensure appropriate levels of security with standard key-sizes. Currently, Skipjack (80-bit key-size) is the cipher of choice, for the software based security protocols like TinySec, SenSec and MiniSec, used in WSNs. However, with the help of exhaustive simulation, experiments and analysis, in this paper, we show that our optimized implementation of the Corrected Block Tiny Encryption Algorithm (XXTEA) (128-bit key-size), can be a good alternative to Skipjack; at least in the resource constrained WSN environments.