Do You MQ Podcast

25 Years of MQTT

Welcome back to doYouMQ! In this episode, in light of the 25th anniversary of MQTT, joined by Andy Stanford-Clark and Peter Niblett, we hear about the history, use cases and future of the protocol. From it’s conception and early adoption, to it’s proliferation and all that’s still to come from the protocol, it’s a very exciting episode indeed!
For those keen listeners amongst you, you may have picked up on the fact that we failed to provide an answer to the burning question: “What happened to MQTT version 4?”…

Well, now here is Andy’s response:

“The answer to the “what happened to v4?” question is that there is a one byte integer in the MQTT CONNECT packet to indicate the protocol version. It was previously “3”, then we moved the specification level to 3.1.1 as the first OASIS / ISO standard, which we called protocol version “4” (one step further on from 3). Logically, the next version after that had to be “5” in the protocol, so we called the specification version “5.0” also, so they are now re-aligned forever :). For a while it was Peter’s and my number one “FAQ”! “

Check out our community blog here: ​

Are you an IBM MQ user? Leave IBM MQ a review:

Documentation: MQTT in IBM MQ:

Associated organizations mentioned:

Eclipse Paho:


ISO/IEC 20922:


IBM Maximo Application Suite:

Get in touch with the guests:
Andy SC: @andysc on X (Twitter) or email
Peter Niblett: Peter Niblett on LinkedIn or email


Special thanks to our guests for this episode:


Andy Stanford-Clark

IBM Distinguished Engineer and Master Inventor

Peter Niblett

STSM, AI Applications - Chief Architect IoT Platform

Previous post
Next post
Related Podcasts
Leave a Reply

Your email address will not be published. Required fields are marked *