An energy efficient security protocol for IEEE 802.11 WLANs

Security protocols in wired and wireless networks make use of computationally intensive cryptographic primitives and several message exchanges for authenticated key exchange at the session level and data confidentiality and integrity at the packet level. Moreover, changes in connectivity require mobile stations to repeatedly authenticate themselves, thereby expending more energy. In this paper, we propose an energy efficient security protocol for wireless local area networks (WLANs) that employs (a) different cryptographic primitives based on their suitability in terms of energy consumption and security level, (b) different levels of security and types of security services depending on the type of packet in 802.11 WLANs, and (c) a light-weight hashed key chain to reduce the number of expensive authentication transactions due to connectivity losses. We use packet traces from three different networks to compare the performance of the energy efficient security protocol with that of the standard 802.11 WLAN security protocol and show significant reduction in energy consumption.