VerneMQ is an Apache2 licensed distributed MQTT broker, developed in Erlang.

MQTT used to stand for MQ Telemetry Transport, but it no longer is an acronym. It is an extremely simple and lightweight publish/subscribe messaging protocol, that was invented at IBM and Arcom (now Eurotech) to connect restricted devices in low bandwidth, high-latency or unreliable networks.

VerneMQ implements the MQTT 3.1 and 3.1.1 specifications, integration of MQTT-SN is planned. Currently the following features are implemented:

• QoS 0, QoS 1, QoS 2
• Basic Authentication and Authorization
• Bridge Support
• $SYS Tree for monitoring and reporting
• TLS (SSL) Encryption
• Dynamic Topics
• Websockets Support
• Cluster Support
• SNMP Monitoring
• Logging (Console, Files, Syslog)
• Reporting to Graphite
• Extensible Plugin architecture
• Multiple Sessions per ClientId
• Session Balancing

For more information head over to the VerneMQ Documentation or to the product page VerneMQ.