MQTT over Websocket

Some components of Drogue Cloud support the MQTT protocol. Unless noted otherwise, all components support MQTT 3.1.1 and 5 not only using the binary MQTT protocol, but also using MQTT over Websockets.

Connecting

Drogue Cloud provides three different, dedicated endpoint for MQTT-enabled service:

  • Plain MQTT

  • MQTT over Websockets

  • MQTT over Websockets without support for X.509 client certificates

These are simply the same services (e.g. MQTT endpoint or integration), but running with different settings on the MQTT protocol layer.

True, it is possible to detect if a connecting client is using MQTT or Websocket. However, it is not possible to detect if a browser based websocket client connects using TLS or if it is a normal one. The difference is, that a browser based websocket client cannot properly establish a TLS session, if the server allows the use of X.509 client certificates.

So instead of providing a mix of auto-detect and additional endpoints, we do offer dedicated endpoint for each connection profile.