Abstract-The applications and utility of Wireless Sensor Network (WSN) have increased its pace in making an entry to the commercial market since the last five years. It has successfully established its association with Internet-of-Things (IoT) and other reconfigurable networks. However, in this advent of exponential progress in technology, WSN still suffers from elementary problems of energy efficiency, scalability, delay, and latency where Medium Access Control (MAC) protocols hold the primary responsibility. This paper reviewed the frequently used MAC protocols and studied their advantages and limitations followed by most recently carried out implementation work towards WSN performance enhancement. The paper finally outlines the unsolved problems from the existing research work and discussed briefly the research gap followed by a chalked out plan of tentative future work to address the research gap from existing review.