Energy Consumption of Encryption Schemes in Wireless Devices

Resources in the wireless environment are limited. The processor has limited capacity and there is limited battery power available. The increasing demand for services on wireless devices has pushed technical research into finding ways to overcome these limitations. As the penetration of wireless devices increases and applications become more critical every day, security of wireless networks has come under heavy scrutiny. However since most of the current communication algorithms are designed and tested for use in the wired environment, they cannot be used directly in Wireless LANs. Encryption, which is the backbone of security protocols, is computationally intensive and consumes energy and computational resources that are limited in wireless devices. The current encryption standards used in wireless systems are not very secure. Also, the wireless network interface draws a significant fraction of total power consumed by the mobile device. Collisions and retransmissions lead to additional consumption of power. To design energy efficient secure protocols for wireless devices there is a need to understand how encryption affects the consumption of battery power with and without data transmission.The research work carried out in this thesis, provides results that encourage having encryption schemes as software implementation in Wireless LANs and provides results reflecting the advantages of doing so. Various symmetric key and asymmetric key algorithms have been evaluated with different key sizes and on different devices. Effect of varying signal to noise ratio and varying packet sizes has been studied. Further, some suggestions for design of secure communications systems to handle the varying wireless environment have been provided