Cost of secure sensing in IEEE 802.15.4 networks

In this paper, we consider interconnected IEEE 802.15.4 beacon enabled clusters with secure and reliable sensing. Clusters are interconnected via bridges implemented on cluster coordinators. Each cluster has to contribute a constant number of packets per second to the sink. Packets are protected with the Message Authentication Code which requires a secret key shared between each node and coordinator. We model network behavior under regular sensing traffic, power management, and periodic key exchanges. Three types of key exchange protocols of varying complexity are considered, and the impact of their communication and computation complexity on the network lifetime is evaluated. Our model and results can be used to determine network and security parameters in IEEE 802.15.4 based wireless sensor network when application requirements and known.