Abstract—Industry 4.0 has imminently emerged as the fourth industrial revolution. It garners emphasis primarily on the interaction between factory equipment and machines involved in entire value-chain activities for boosting efficiency and production with limited human intervention. The M2M communication protocols have gained significant prominence amidst sage minds in recent years, particularly in the manufacturing industries. Several M2M communication protocols have been developed for the industry, such as SECS/GEM, OPC UA, DDS, and MQTT. Among these protocols, SECS/GEM is a semiconductor’s equipment interface protocol for equipment-to-host data communications. It is not a modern, but decades-long protocol, and has been again brought to the fore by Industry 4.0. Thereupon, it was imperative to review amenability of SECS/GEM protocol in the context of adaptation of features depicted by industry 4.0, and limelight plethora of shortcomings and limitations. In this paper, comparisons of prominent features and limitations of the aforementioned M2M communication protocols in general and review of the SECS/GEM protocol in particular, have been made. Findings include deficiencies in security, point to point communication, discovery mechanism, fixed message format, interoperability, extendibility, and manual integration. 
​