設計與實作一個適用於無線感測網路下雙節點 系統之檢查點與重啟點機制

Abstract

Wireless sensor networks are expected to work for a long period of time. Furthermore, lots of wireless sensor network applications are deployed in the rigorous environments. As a result, sensor nodes are usually prone to errors and would miss their function during their lifetime. In this paper, on the basis of dual-mote architecture, we thus implement a checkpoint/restart scheme for wireless sensor nodes. In addition, due to the considerations of cost and energy consumption, the microcontroller in each wireless sensor node usually does not have the memory management unit. Consequently, we also design three incremental checkpoint schemes in the MMU-Less sensor nodes. We leverage the idea of sandboxing to track the memory regions changed during each checkpoint period. The three incremental checkpoint mechanisms differ in the checkpoint data size and system execution overhead. The smaller the checkpoint data size is, the larger the execution overhead. We have implemented our system in the Mica2 mote. For the experimental result, the operations take less than 6.5ms on the sensor node platform. Consequently, our proposed scheme can effectively increase the reliability of the sensor networks with neglected overhead.