6.2 Use of MQTT

MQTT includes reliability features which allow recovery from loss of network connectivity without requiring explicit involvement of the applications that are using it, however to do this it requires an underlying network protocol that provides ordered, lossless, bi-directional connections. The MQTT standard [1] allows a choice of underlying protocol. The present document restricts this choice: it shall be one of the following:

• TCP/IP.
• TCP/IP with Transport Level Security (TLS) 1.2
• WebSocket - either with or without the use of TLS 1.2.

See the MQTT standard [1] for considerations on how to use these protocols with MQTT.