Impact of Reliable and Secure Sensing on Cluster Lifetime in IEEE 802.15.4 Networks

Abstract

In order to penetrate the market with cost-effective solutions for wireless sensor networks (WSNs) we need standardized low cost, low power, and short-range communication [low rate wireless personal area network (LR-WPAN)] AU1 technology. An important candidate for the application in this area is the IEEE 802.15.4 standard [1]. The 802.15.4 specification outlines some basic security services at the data link layer that can be combined with advanced techniques at the upper layers to implement a comprehensive security solution. For example, the recent ZigBee specification [2] implements a number of protocols—including securityrelated ones—that can be deployed in an 802.15.4 network. Given that the 802.15.4 devices are typically severely constrained in terms of their communication and computational resources, the implementation of such solutions is likely to impose a significant performance overhead. For cost effectiveness we assume that symmetric-key key establishment (SKKE) [2] is implemented over the IEEE 802.15.4 sensor cluster operating in beacon-enabled, slotted carrier sense multiple-access/collision avoidance (CSMA/CA) mode. In this chapter we address the problem of multicluster sensor network as shown in Fig. 16.1 with integrated node sleep control and key exchange mechanism. The network is formed by three clusters interconnected in a master–slave regime wherein the coordinator of a lower cluster acts as the bridge to the upper one, and the coordinator of the topmost cluster acts as the network sink. In our previous work [3] we analyzed the impact of contention caused by the bridges and ordinary nodes on the cluster lifetimes. In this chapter we include the model of additional traffic caused by key exchanges in