Cross-Layer Secrecy Design on TCP/IP and 802.11 for Energy Saving

Electronic services (mail, web, etc.) can operate, at present over wireless networks. 802.11 networks are an example, where wireless devices use its resources to access to networks and services and in particular to Internet. The security mechanisms in the MAC layer are added to existing security mechanisms in other layers of the TCP/IP model, and therefore it generates multiple encryption of information. The implementation of encryption mechanisms in wireless networks consumes resources in the devices, and among others, the battery power. In a wireless terminal the battery is limited and the reduction of the number of encrypted bytes can reduce the energy consumption. In this paper we resume the security architecture in TCP/IP over IEEE 802.11 networks. Then we explain the impact of encryption mechanisms on the energy consumed in a mobile node in a case scenario. We propose a solution that eliminates redundancy in the encryption of the data at different layers applying the Cross-Layer design, we analyze the architecture for exchanging security information between layers and, finally, we propose an algorithm for security inter-layer communication and a solution for Cross-Layer signalling between nodes.