| Wireless Sensor Networks (WSNs) usually consist of a large number of sensors which have the ability to detect events, generate reports and transmit them to the sink which collects the data reports. The mobile sink has been adopted to improve network performance of WSNs. It is necessary to inform sensors of a topological or location change of a moving sink, however frequent location updates from mobile sinks can lead to high energy consumption of sensors, and therefore shorten the network lifetime. Many protocols have been proposed in the past few years trying to achieve the energy efficiency goal in WSNs with mobile sinks. This thesis investigates six protocols: TTDD, Locator, LURP, Efficient Routing, TwinRoute and Dual-Sink. First, they are implemented in ns-2, then extensive performance evaluations are conducted. Furthermore, the experimental results are compared and analyzed. This thesis reveals both the advantages and performance issues of these protocols, and it provides the basis for future research. |
