How does one evaluate the performance of the classic flooding routing protocol in wireless sensor networks? This paper suggests using sense count, receive count, and receive redundant count as metrics. The protocol performance is affected by the sensor distribution strategy in the network. The authors evaluate eight types of distribution through simulations and compare the results.
Wireless sensor networks, as a versatile solution to many research and development problems, have become increasingly popular. For those not familiar with sensor networks, these consist of usually small-form-factor devices equipped with sensory and wireless communication capabilities. Such devices are known or abstracted as nodes. Due to the limited energy and the minimum processing capabilities, energy conservation is one of the major topics in the wireless sensor networks area. A sensor node consumes energy when it, for example, processes packets or partakes in wireless communication. It is commonly believed that radio transmission consumes the most energy. Transmission can be broadly categorized into data transmission and control transmission. To collect data from the sensors, the nodes send to a master node or base station, either directly or indirectly, depending on the underlying structure of the network. In order to form a communication channel and working topology, link states are collected and exchanged. A classic method for this purpose is flooding, in which the master node broadcasts to its neighbor nodes and the neighbor nodes broadcast to their neighbor nodes. The broadcast can be selective to reduce overhead and contention.
The paper attempts to investigate the effects the distribution of sensor nodes has on the performance of the flooding protocol. However, the authors have not been completely clear on the term “distribution” throughout the paper. The cited reference on normal distribution focuses on the distribution of the sensor gain, which is the gain of the received signal over the originally transmitted signal. The reference on gamma distribution deals with the delay that follows it. Some of the text in the paper talks about network distribution, which indicates the placement or deployment.
An apparent weakness of the paper is its lack of technical depth. The majority of the technical content is focused on the expressions for the eight distributions, which are known statistics. The performance is discussed on results obtained solely from simulations.
In order to fully understand the paper, one will likely need to read up on many cited references. The presented results will be more interesting to those working closely on the flooding protocol than to general researchers on wireless sensor networks.