Optimizing the Energy Consumed by Secure Wireless Sessions – Wireless Transport Layer Security Case Study

In this paper we identified the various sources of energy consumption during the setup, operation and tear down of a secure wireless session by considering the wireless transport layer security protocol. Our analysis showed that data transfers during a secure wireless transaction, number and size of messages exchanged during secure session establishment and cryptographic computations used for data authentication and privacy during secure data transactions in that order are the main sources of energy consumption during a secure wireless session. We developed techniques based on information compression, session negotiation protocol optimization and hardware acceleration of crypto-mechanisms to reduce the energy consumed by a secure session. A mobile test bed was developed to verify our energy management schemes and to study the energy consumption versus security tradeoffs. Using our proposed schemes we were able to reduce the session establishment energy by more than 6.5× and the secure data transaction energy by more than 1.5× during data transmission and by more than 2.5× during data reception.