MQTT X
Powerful cross-platform MQTT 5.0 desktop, CLI, and WebSocket client
... Transport. It is a publish/subscribe, extremely simple and lightweight messaging protocol, designed for constrained devices and low-bandwidth, high-latency or unreliable networks. To run MQTT Broker locally, EMQX is recommended: An Open-Source, Cloud-Native, Distributed MQTT Broker for IoT. After the MQTT is connected successfully, you can perform MQTT publish and subscription tests.