Practical guides on MQTT, managed brokers and connected products from the ConnectMQ team.
An industrial MQTT broker carries plant state, not just messages. This guide explains the capabilities that matter on the factory floor, from Sparkplug awareness and retained state to security and visibility, with a script to test them yourself.
A practical comparison of the ESP32 and Raspberry Pi Pico W for connected projects, covering hardware, Wi-Fi and Bluetooth, programming options, TLS performance, low-power modes and MQTT code on both.
Use an ESP32 as a Bluetooth Low Energy scanner that collects advertisements from nearby sensors and beacons, filters and deduplicates them, and publishes them to per-device MQTT topics.
Control LED strips and dimmers over MQTT with an ESP32, use JSON commands with smooth transitions, store scenes as retained messages and run schedules from a small Python service.
Wire a 4-channel relay board to a Raspberry Pi, control each channel from MQTT topics with Python and gpiozero, and use retained messages so every relay returns to the right state after a reboot or power cut.
A practical guide to retrieval-augmented generation for factories: index manuals and procedures, pull current values from MQTT topics and give technicians answers grounded in both, with citations.
The retain flag lets an MQTT broker hand every new subscriber the last known value on a topic immediately. Learn how it works, where it shines and where it causes stale-data bugs.
MQTT bridging forwards selected topics between brokers so each site keeps a local broker while the cloud sees everything. Learn the patterns, a Mosquitto bridge config and a Node-RED alternative pointing at ConnectMQ.
Build a two-way KNX MQTT bridge with xknx and paho-mqtt that decodes KNX telegrams into JSON, publishes them to a broker and turns MQTT commands back into group writes.
Install and configure Grafana's MQTT data source plugin, stream numeric and JSON payloads from broker.connectmq.com into live panels, and decide when a time-series database such as InfluxDB is the better choice.
A practical bearing temperature monitoring setup: battery-powered wireless sensors on bearing housings, ambient-compensated readings over MQTT, rate-of-rise detection and threshold alerts that fire before a bearing overheats.
MQTT 5 is more than a version bump. Learn the features that change how you build IoT systems, from reason codes and expiry to shared subscriptions and request/response, with hands-on examples.
A Sparkplug rebirth makes an edge node republish its births so a host can rebuild an accurate view. This troubleshooting guide covers NCMD rebirth, sequence gaps, unknown aliases, rebirth storms and a step-by-step diagnostic flow.
Why publish/subscribe suits multi-agent AI systems, and the topic conventions, MQTT 5 features and safety rules that let agents discover each other and exchange messages through a broker.
A practical 12-point checklist for choosing an IoT MQTT broker, a table of questions to ask every vendor, and a five-minute hands-on test you can run against broker.connectmq.com.
How to test MQTT client code at every level: pure unit tests with mocks, integration tests against a containerised Mosquitto broker in CI, and end-to-end smoke tests against a real cloud broker.
Sparkplug B and plain JSON both run on any MQTT broker, but they solve different problems. This comparison covers interoperability, state awareness, bandwidth, tooling and a hybrid pattern that gives you both.
Learn how to remap messy, flat device topics into a structured ISA-95 namespace with a Node-RED lookup table, normalise payloads on the way, and republish everything to a ConnectMQ broker without creating loops.
Choosing between the ESP32 and ESP8266 for an MQTT device? This comparison covers memory, TLS capability, peripherals, power, library support and cost, with clear recommendations by project type.
Wire a relay module to an ESP32, switch it from an MQTT command topic and publish retained state so every dashboard and app always knows whether the load is on or off.
How to create a building digital twin that links BIM geometry with live HVAC, occupancy and energy data streamed over MQTT, with topic design, code and a rollout checklist.
broker.connectmq.com is a free public MQTT broker for testing and learning. Here are the ports, the anonymous access rules, the limits and copy-paste examples for the CLI, Python, Node.js and the browser.
A fair, practical open source MQTT broker comparison covering Mosquitto, EMQX, VerneMQ and NanoMQ, with Docker commands to try each one and guidance on when a managed service makes more sense.
A practical guide to the $SYS topic tree: where it comes from, why wildcards skip it, what Mosquitto-style brokers publish there and how to watch client connection state on ConnectMQ.
A tour of the features that make an MQTT broker management console useful day to day: broker setup, credentials, live topics, a web client, connection status, alerts and industrial views, using the ConnectMQ portal as the example.
A practical walkthrough of how to build a unified namespace, from modelling your plant hierarchy and choosing a broker to publishing retained state from the edge and adding the first consumers.
Edge AI means running machine learning inference on or near the device that collects the data. This explainer covers how it works, the hardware tiers, and why edge devices should publish results rather than raw data.
Two proven ways to get data out of an S7-1200 or S7-1500 over MQTT: the PLC-native LMQTT library and an external Python gateway using python-snap7, with TLS, ISA-95 topics and report-by-exception.
A defender's overview of MQTT vulnerability classes in brokers, clients and deployments, with concrete mitigations and a patching strategy that does not depend on luck.
MQTT routes through a broker; DDS lets peers discover each other and exchange typed data directly. This comparison covers architecture, real-time guarantees, robotics versus IIoT use and how to bridge the two.
Create an account, get your broker credentials and connect your first device — no servers to install, patch or scale.
