MQTT protocol

MQTT protocol

Specification

The current formal MQTT protocol specification can be found at:

• MQTT v3.1.1 specification

The current MQTT-SN specification from IBM can be found at:

• MQTT-SN v1.2 specification

Clarifications

As questions arise around particular aspects of the specification, we are collecting clarifications:

• [Topic format](Topic format)

• [Security considerations](Security considerations)

• [Are topics dynamic](Are topics dynamic)?

• [Overlapping topics](Overlapping topics)

• [KeepAlive for the client](KeepAlive for the client)

• [Miscellaneous clarifications](Miscellaneous clarifications)

• [MQTT over Websockets](MQTT over Websockets)

• [Duplicates on QOS 0](Duplicates on QOS 0)

• [Clarify UTF8 strings](Clarify UTF8 strings)

• [Will Message UTF8 Support](Will Message UTF8 Support)

• [ClientID autogeneration](ClientID autogeneration)

Ideas for future enhancement

Ideas (and reasons for why they may be required) are being collected here:

• [ClientID autogeneration](ClientID autogeneration)

• [Topic string enhancement](Topic string enhancement)

• [Broker auto-discovery](Broker auto-discovery)

• [URL scheme](URL scheme)

• [Status field for acks](Status field for acks)

• [Add messageid to ping](Add messageid to ping)

• Will Message UTF8 Support

• [Bridge protocol](Bridge protocol)

• [Extended CONNACK codes](Extended CONNACK codes)

• [Registered topics like MQTT-S](Registered topics like MQTT-S)

• MQTT for Centralised Data Collection

• [Time To Live for retained message](Time To Live for retained message)

Items fixed in the updated OASIS spec

• [Extended ClientID](Extended ClientID)

• [Short usernames and passwords](Short usernames and passwords)