Bapat et al. present a set of protocols for monitoring the state of wireless sensor networks. They call their monitoring protocols Chowkidar, which means “watchman” in Hindi and is thus an appropriate name for a set of protocols that monitor the state of devices in wireless sensor networks.

The motivation for developing these monitoring protocols stems from the practice of using low-cost and unreliable devices in the construction and deployment of most wireless sensor networks, which leads to the need to constantly anticipate the running condition of the devices in the sensor network.

The authors examine related work and indicate the differences and the shortfalls, when compared to their own monitoring protocols. They present their protocols, as well as elaborate arguments to prove their correctness and to demonstrate that node or link failures in the wireless sensor network should not be confused with a problem in the monitoring protocol itself. Bapat et al. also prove their protocols’ robustness and their tolerance to failures, despite nonresponsive links and nodes, especially in the tree formation protocol.

The paper reports on a number of experiments that the authors ran to measure performance, using their distributed Chowkidar protocol; the results are then compared with those of a centralized version of their protocol. Two tables and 11 figures are carefully employed to prove the correctness and robustness of the various protocols that constitute the Chowkidar monitoring protocol.