Energy-efficient protocols for environmental monitoring in wireless sensor networks: A review

A wireless sensor network (WSN) is defined as an infrastructure-less wireless network containing a substantial amount of the sensor's data deployed in an ad hoc manner to form a network. Sensor nodes are used along with onboard process data to monitor the environment in a particular area. Sensors are connected to the base station, which also functions as a processing unit within the WSN system. A base station is used to share the data with the help of the internet. Sensor nodes within WSN have limited power, resulting in a reducing lifespan, especially in human-inaccessible locations. This paper reviews the energy-efficient protocols for environmental monitoring and energy-harvesting WSNs. This paper investigates three protocols, viz., the low energy adaptive clustering protocol, the distributed energy-efficient clustering protocol, and the stable election protocol. The result-driven approach followed in this paper presents a comparative analysis of these protocols to find the best protocol for energy efficiency. Throughput indicating packets received successfully at the base station has been evaluated in this paper. This metric indicates the effectiveness of the protocols in achieving a longer lifespan for the sensors. Furthermore, the dynamic deployment and challenges associated with environmental monitoring applications, considering the physical, network, and medium access control layers, have been discussed in this paper. Given the above, this paper presents a systematic literature review to identify the interdisciplinary work done by researchers towards the applications of WSNs in the field of environmental monitoring.