Improvement of MQTT semantic to minimize data flow in IoT platforms based on distributed brokers

Abstract Message queuing telemetry transport (MQTT) is an application layer protocol that enables effective device communication in the Internet of Things (IoT). MQTT operates according to a publish‐subscribe model, where a broker receives messages from the publishers and then forwards them to the subscribers. However, existing cloud‐based MQTT brokers lead to network bottlenecks due to the large number of devices that interact with them. Therefore, mist computing is involved, where the MQTT brokers are deployed closer to the IoT devices and the workload is distributed across multiple brokers. Nevertheless, the distributed mist‐based MQTT architecture introduces serious issues caused by the massive volume of flow exchanged by IoT devices. In this article, we introduce MQTT‐SD to address these issues. MQTT‐SD enhances MQTT protocol syntax with fusion semantic aggregation. It accomplishes MQTT topic fusion on the MQTT broker side with consideration of topics' distribution. We carried out extensive simulation and emulation to demonstrate MQTT‐SD efficacy. The results show that MQTT‐SD reduces MQTT flow and has the lowest traffic load compared to MQTT+ and MQTT‐MFA.