Evaluating and Improving Message Response Time in Internet of Things (IoT) Communication Protocols: A Comprehensive Framework

The Internet of Things (IoT) relies on various communication protocols to enable efficient data exchange among devices, sensors, and applications. One such widely used protocol is MQTT (Message Queuing Telemetry Transport), which operates on a publish/subscribe model, providing a lightweight and scalable solution for IoT communication. This study explores the performance of IoT systems using MQTT, focusing on key factors such as network buffering, broker memory, and Quality of Service (QoS) levels that influence message response times. The study employs Stochastic Petri Nets (SPN) to model the MQTT-based publish/subscribe system, capturing system dynamics and predicting response times under varying conditions. By optimising these factors, the study demonstrates how to reduce response times and improve system performance. Experimental results highlight the significant impact of network buffering, broker memory, and QoS levels on the overall efficiency of the IoT system. Network buffering and broker memory increase response times, while adjusting QoS levels can either improve or degrade performance based on application needs. This research provides valuable insights into optimising IoT communication, enhancing the reliability and efficiency of MQTT-based systems.