Real-time monitoring with PRISM: Simulation and performance evaluation using Castalia

This article describes our experience from the implementation of PRISM in the Castalia simulator. PRISM is a recently-proposed protocol for real-time monitoring in single-hop and multi-hop wireless sensor networks. The protocol allows to define the maximum number of nodes, the requirements on the network synchronization and the data-rate in a flexible manner, in order to accommodate for different types of acquisitions. A formal description of the performance bounds of PRISM for varying network size, channel capacity, and data-rate is currently available. Although a theoretical performance analysis has been performed, there are a number of practical issues that are not addressed in the original protocol description and which have an impact on its resulting performance. In addition, the scalability of PRISM and its actual performance when deployed in multi-hop networks are still unknown. To this aim, we have implemented PRISM in the open-source wireless sensor network simulator Castalia. Extensive simulations have confirmed the effectiveness and the efficiency of the protocol, and the implementation in Castalia has provided important insights into synchronization issues.