Performance Evaluation of OPC UA and MQTT for ETAT Smart Lab (ESL)

The Eastern Economic Corridor (EEC) serves as a key and central strategic initiative within the broader Thailand 4.0 framework. The ETAT project aims to establish dedicated engineering education and training centers for participating universities, providing essential support and skills development opportunities for engineers and young professionals. As one of the project partners, Rajabhat Rajanagarindra University (RRU) has undertaken the development of the ETAT Smart Lab to design a smart agricultural system that incorporates the Internet of Things (IoT), programmable logic controllers (PLCs), and Raspberry Pi. In this study, we focus on the ETAT Smartlab environment, specifically on the task of transferring data from RS-485 Modbus sensors to the PLCnext platform using both OPC UA and MQTT protocols. Our method for evaluating performance in this context focuses on measuring the time stamp differences between the source and destination endpoints. The research shows that the OPC UA protocol provides superior performance for transmitting sensor data to ETAT Smart Lab.