Towards an IoT-based Water Quality Monitoring System with Brokerless Pub/Sub Architecture

This paper investigates a real-time water quality monitoring system by using a proposed brokerless publisher-subscriber (pub/sub) architecture framework. On the system, sensors sense the water measurement metrics, including temperature, pH, and dissolved oxygen level. All collected data are stored in a database and computed stochastically for further analysis on water quality. A complementary experiment compares the proposed pub/sub architecture and MQTT, a lightweight protocol on which IoT mostly uses, to show better performance of the proposed architecture in case of network latency and throughput for diverse message payload size, thus suggesting the future IoT implementation of the system. To complete the experiment, the relationship among temperature, pH, and dissolved oxygen is analyzed, and the experiment summarizes that water temperature is inversely proportional to pH and dissolved oxygen value.