Factory Digital Twin: Use Cases and Architecture
A practical guide to factory digital twin use cases and architecture, showing how line-level and plant-level twins are fed by ISA-95 structured MQTT data.
8 min read
Blog
MQTT and IoT guides
Practical guides on MQTT, managed brokers and connected products from the ConnectMQ team.
All articles
ESP32 Digital Twin: A Beginner Project with MQTT and a 3D Browser Model
A beginner-friendly ESP32 digital twin: the board publishes a potentiometer, a button and an LED state over MQTT, a Three.js model in the browser mirrors them in real time, and clicking the 3D LED switches the real one.
6 min read
ESP32 MQTT Tutorial: Publish Sensor Data and Control an LED with Arduino IDE
Connect an ESP32 to an MQTT broker with Arduino IDE and PubSubClient, publish JSON temperature readings, control the onboard LED from the command line and upgrade to TLS with portal credentials.
9 min read
Sparkplug Metric Aliases: Saving Bandwidth in DATA Messages
Sparkplug metric aliases replace long metric names with small integers in DATA messages. This guide explains how the mapping works, when to use it, and how to debug alias mismatches.
9 min read
10 Raspberry Pi 5 IoT Projects with MQTT (From Sensor Hubs to AI Cameras)
Ten practical Raspberry Pi 5 IoT projects that use MQTT for messaging, with the hardware, topic layout and starting code for each, from a home sensor hub to an AI camera and a factory gateway.
8 min read
Python MQTT TLS: Connecting Securely on Port 8883 with paho-mqtt
Encrypt your Python MQTT traffic with paho-mqtt and TLS on port 8883: use the system CA store, keep hostname verification on, fix the common certificate errors, and connect over secure WebSocket when only 443-style ports are open.
7 min read
Power Quality Monitoring in Manufacturing: Harmonics, Sags and Power Factor over MQTT
Unexplained drive trips, hot transformers and power factor penalties all trace back to power quality. Learn what to measure, how analyzers report it and how to stream summaries and events over MQTT.
7 min read
Node-RED Subflows for Reusable MQTT Logic
Node-RED subflows turn repeated groups of nodes into one reusable node. This explainer shows how to build an MQTT alert subflow with instance properties, status reporting and error handling, and how to reuse it across many topics.
7 min read
Node-RED S7: Read Siemens PLC Variables and Publish to MQTT
Connect Node-RED to a Siemens S7 PLC with node-red-contrib-s7: enable PUT/GET in TIA Portal, address data block variables correctly, publish changes to MQTT and handle setpoint writes safely.
8 min read
MQTT OT Security: Protecting Industrial Plants When Sending Data to the Cloud
How to move data from PLCs and machines to a cloud MQTT broker without opening the plant network: outbound-only design, DMZ patterns, segmentation, credentials and monitoring.
8 min read
Build a Real-Time MQTT Chat App with JavaScript, Presence and No Local
Build a browser chat app on MQTT over secure WebSocket, with rooms, retained presence that survives crashes via Last Will, and the MQTT 5 No Local option, running on broker.connectmq.com.
7 min read
MQTT Broker Monitoring: The Metrics That Matter and How to Watch Them
Learn which MQTT broker metrics actually predict trouble, how to alert on them without noise, how to build an end-to-end latency probe, and how to watch your broker in the ConnectMQ portal.
7 min read
Motor Current Monitoring with CT Clamps and MQTT for Early Fault Detection
Clip a CT clamp around a motor lead, measure RMS current with an ESP32, publish it over MQTT and use a small Python service to detect overloads, frequent starts and drift away from normal load.
7 min read
mosquitto_pub mosquitto_sub Examples: 25 Practical Commands for MQTT Testing
A copy-paste reference of 25 mosquitto_pub and mosquitto_sub commands covering QoS, retained messages, Last Will, TLS, output formatting and MQTT 5 properties, all runnable against broker.connectmq.com.
7 min read
IT/OT Convergence Explained: Culture, Architecture and a Shared Data Layer
IT OT convergence is less about merging networks and more about giving two very different teams the same trustworthy data. This explainer covers the cultural gap, the technical building blocks and a practical shared-namespace pattern built on MQTT.
7 min read
Structuring an ISA-95 Digital Twin with the Equipment Hierarchy
A guide to using the ISA-95 equipment hierarchy to organize digital twin models and MQTT topics, including Sparkplug B republishing, naming rules and a validation script.
7 min read
Industrial AI Copilot for Operators: Grounding Answers in Live ISA-95 Data
An industrial AI copilot is only as good as the data it can see. This guide shows how to ground an operator assistant in live, ISA-95 structured MQTT topics so its answers are current, traceable and safe.
9 min read
Raspberry Pi Zero 2 W MQTT Sensor Node: Compact, Low-Power and Reliable
Build a small, headless Raspberry Pi Zero 2 W sensor node that reads a BME280, publishes environment and health data over MQTT 5, uses less power and survives months of unattended operation.
7 min read
Raspberry Pi Power Monitor with MQTT: Measure Voltage, Current and Energy
Measure voltage, current, power and accumulated energy with a Raspberry Pi and an INA219, publish the readings as JSON over MQTT, and learn when to use a CT clamp HAT for AC mains circuits instead.
7 min read
MQTT vs NATS: Choosing a Messaging System for IoT
MQTT and NATS are both lightweight publish/subscribe systems, but they target different clients. This comparison covers device support, delivery guarantees, persistence and ecosystem so you can place each one correctly.
7 min read
MQTT Username and Password Authentication Explained
How usernames and passwords travel in the MQTT CONNECT packet, why they must always be paired with TLS, how brokers reject bad credentials and how to manage per-device credentials on a managed broker.
7 min read
MQTT Rate Limiting and DoS Protection Explained
How MQTT brokers defend against connection floods, publish storms and oversized payloads, what limits a managed broker applies, and how to write clients that respect them.
8 min read
iOS MQTT Swift Client with CocoaMQTT and SwiftUI
Step-by-step iOS MQTT Swift tutorial: add CocoaMQTT with Swift Package Manager, wrap it in an ObservableObject, show live sensor data in SwiftUI and publish commands over TLS.
7 min read
Homebridge MQTT: Bringing MQTT Devices into Apple Home
Expose MQTT sensors, switches and lights as HomeKit accessories with Homebridge and the mqttthing plugin, including JSON payloads, TLS credentials and a sensible topic layout.
7 min read
Home Battery Monitoring with MQTT: State of Charge, Cell Voltages and Low-Battery Alerts
Publish BMS data such as state of charge, pack voltage, current, cell voltage spread and temperature to an MQTT broker, then add low-battery and imbalance alerts with hysteresis so you hear about problems before the inverter shuts down.
7 min read
Wind Turbine Digital Twin: Load, Yield and Maintenance with MQTT
How wind turbine digital twins use SCADA data published over MQTT to monitor yield against the power curve, estimate loads and plan maintenance, with topic design and code.
6 min read
Predictive Maintenance with Machine Learning: Features, Labels and Models
A practical guide to predictive maintenance machine learning: which condition data to collect over MQTT, how to engineer features and labels, which models to start with, and how to validate them honestly.
7 min read
Designing IoT Clients to Survive an MQTT Broker Outage
Every broker restarts eventually. Learn the client-side patterns that turn an MQTT broker outage into a non-event: jittered reconnects, offline buffering, Last Will status, session handling and idempotent commands.
8 min read
MQTT Broker High Availability: Concepts, Client Design and Questions to Ask
High availability for MQTT is a shared responsibility between broker and clients. Learn the core concepts, the failover behavior to expect, how to design resilient clients, and the questions to ask any provider.
8 min read
Industry 4.0 Technologies: The 9 Pillars Explained
The nine pillars of Industry 4.0 are often presented as separate technologies. This explainer walks through each one in plain terms and shows how a shared MQTT messaging layer is what actually connects them on a real plant floor.
8 min read
Your private MQTT broker is a few clicks away
Create an account, get your broker credentials and connect your first device — no servers to install, patch or scale.