A Review on Unequal Clustering Protocols in Wireless Sensor Networks

Wireless Sensor Networks (WSN) and Internet of Things assisted networks have entered almost all domains of human life in the recent years, and as a result of their wide variety of uses, they are still a popular focus of research. A key problem in the development of WSNs is energy efficiency. A useful technique to preserve energy in a WSN is clustering. However, it has an issue of hot spots. The hot-spot concern can be handled by using unequal clustering, wherein clusters of different sizes are created depending on distance from the sink/base station. In this article, a brief of the recent unequal clustering methods and trends in WSNs is presented. The classification of uneven clustering techniques in WSNs is presented, and future research directions in the field are recommended.