Lightweight Cryptographic Algorithm : Variable Key Length Encryption Algorithm (VEA)

Wireless networks applications are growing very fast although their nodes suffer from limited bandwidth, memory, and processing capabilities. They operate on unattended mode in hostile environments and the sensitive data should be protected using some sort of cryptography. Due to the limited computing power of wireless devices, it is impossible to use asymmetric cryptography approaches for the session key establishment or to apply one of the traditional advanced encryption algorithms for the data encryption. Therefore, VEA is proposed in this paper as an appropriate cryptography algorithm for wireless networks due to its low energy consumption, simple hardware requirements and suitable level of security. In addition, the algorithm has an important advantage over the current cryptography algorithm in which variable key length can be used. VEA tries to overcome the limitations of both public- and symmetric-key protocols. VEA relies its design on a smart version of Feistel structure.