| In the wireless sensor network (WSN) literature, the use of a mobile sink is commonly viewed as one of the most successful means of load balancing as well as an effective defence against the so-called hot-spot phenomenon. In this thesis, we present a thorough analytical and simulation-based investigation of various network-performance aspects related to the use of mobile sink(s). In particular, we examine the pros and cons of deploying path-constrained sink mobility - both from the general theoretical perspective as well as in the framework of real-world IEEE 802.15.4 / ZigBee-based WSNs.;We also introduce two simple modifications to the ZigBee standard aimed at dealing with the challenges associated with the use of mobile sink(s): Suppressed Route Discovery and Node Association Based on Residual Energy mechanisms. Moreover, an extension of the two mechanisms, Progressive Footprint Chaining method, is also proposed with the goal to enable further reduction of the mobility-related overhead in ZigBee-based sensor networks.;We conduct a detailed theoretical analysis of the mobile sink deployment strategy that has been identified, in the past literature, as the most realistic - multi-hop data delivery with path-constrained sink trajectory. We present sample results of our OPNET-based study aimed at examining the real-world applicability of the multi-hop data delivery with path-constrained sink trajectory strategy. |
