--- title: "MQTT Broker for Prototyping & Education | ConnectMQ" description: "The quickest way to make things talk: start on the public shared endpoint with code samples for Python, Node.js and ESP32, then move to a private broker." url: "https://connectmq.com/prototyping-education/" language: "en" --- Prototyping & Education # MQTT for Prototyping & Education From a first ESP32 project to a classroom lab, MQTT is the quickest way to make things talk. Start on the public shared endpoint, then move to a private broker when it gets real. [Try it free](https://app.connectmq.com/signup) [Quickstart](https://connectmq.com/developers/) No card required What you can build ## Build your first connected project on ConnectMQ You build the project, ConnectMQ moves the data. Boards and laptops publish readings; a dashboard, a Node-RED flow or a classmate’s script subscribes — no server to set up. Your boards **ESP32 / Arduino**lab/{team}/esp32/temperature **Raspberry Pi**lab/{team}/pi/sensors **Python scripts**lab/{team}/script/out **CLI (mosquitto)**lab/{team}/test **ConnectMQ** - secure WebSockets - TLS on 8883 - QoS 0, 1 and 2 - retained messages What you build on top **Class dashboard** **Node-RED flows** **Grading & data export** **Student apps** What you get ## Prototyping & Education on ConnectMQ - Try the public shared endpoint broker.connectmq.com with any MQTT client - Code samples for Python, Node.js, ESP32, Go and the CLI - Private broker when public sandboxes are no longer enough example topic design ``` lab/team-3/esp32/temperature lab/team-3/esp32/led/set ``` From first blink to production ## Start small, grow without rewriting Every step uses standard MQTT, so the same code moves from the public broker to a private one by changing the host, port and credentials. 1. No sign-up ### Public broker - broker.connectmq.com, port 1883 - Shared: anyone can read the topics - Ideal for a first test 2. Private ### Free plan - No card required - TLS and your own credentials - Up to 5 connections 3. Production ### Basic or Scale plan - Up to 1,000 connections - Up to 10,000,000 session minutes a month - Same code, new credentials Real-life example ## Students control a lab board from home A favourite classroom project with MQTT: an ESP32 on the lab bench at school, a Python script on a student’s laptop at home, and ConnectMQ in the middle. No firewall rules at school, no server to set up. School lab → ConnectMQ → Student at home. A ten-line Python script publishes a command to the team’s board. Subscribed to its team’s topics: it switches the LED on and publishes its state with the room temperature. Receives the state through ConnectMQ and prints it — the round trip takes well under a second. Every team has its own topics and credentials, so boards and scripts never get in each other’s way.ConnectMQMQTT broker · TLS 8883$ python led.py→ led/set on← led: on← temp: 24.6Student at homePython script · laptopMQTT lablab/+/esp32/#Team 3ESP3224.6 °CSchool labESP32 + LED + sensor · school Wi-Filab/team-3/esp32/led/set {"on":true}lab/team-3/esp32/led/set {"on":true}lab/team-3/esp32/state {"led":true,"temp":24.6}lab/team-3/esp32/state {"led":true,"temp":24.6}Team 3 · nowLED is on — lab at 24.6 °CSchool lab → ConnectMQ → Student at home. A ten-line Python script publishes a command to the team’s board. Subscribed to its team’s topics: it switches the LED on and publishes its state with the room temperature. Receives the state through ConnectMQ and prints it — the round trip takes well under a second. Every team has its own topics and credentials, so boards and scripts never get in each other’s way.ConnectMQMQTT broker · TLS 8883$ python led.py→ led/set on← led: on← temp: 24.6Student at homePython script · laptopMQTT lablab/+/esp32/#Team 3ESP3224.6 °CSchool labESP32 + LED + sensor · school Wi-Filab/team-3/esp32/led/set {"on":true}lab/team-3/esp32/led/set {"on":true}lab/team-3/esp32/state {"led":true,"temp":24.6}lab/team-3/esp32/state {"led":true,"temp":24.6}Team 3 · nowLED is on — lab at 24.6 °C 1. 20:15 **Student’s laptop at home** A ten-line Python script publishes a command to the team’s board. `lab/team-3/esp32/led/set → {"on":true}` 2. 20:15 **ESP32 on the lab bench** Subscribed to its team’s topics: it switches the LED on and publishes its state with the room temperature. `lab/team-3/esp32/state → {"led":true,"temp":24.6}` 3. 20:15 **Student’s script** Receives the state through ConnectMQ and prints it — the round trip takes well under a second. 4. 20:16 **The whole class** Every team has its own topics and credentials, so boards and scripts never get in each other’s way. **Start without an account:** try the same script on the free public broker `broker.connectmq.com:1883`, then move the class to a private broker. [Python code sample](https://connectmq.com/code-samples/python/) [ESP32 code sample](https://connectmq.com/code-samples/esp32/) Platform ## Features that help with Prototyping & Education [ ### Connectivity MQTT 3.1.1 and 5 over TCP, TLS, WS and WSS Learn more](https://connectmq.com/connectivity/)[ ### Dashboard & monitoring Live topic cards, signals and ISA-95 workspace Learn more](https://connectmq.com/monitoring/)[ ### Rules & alerts Threshold rules, alert log and notifications Learn more](https://connectmq.com/rules-alerts/) Solutions ## Other ways teams use ConnectMQ [ ### Industrial IoT & Smart Manufacturing Machines, PLC gateways, OEE and quality data ](https://connectmq.com/industrial-iot/)[ ### Smart Home Hubs, sensors and Home Assistant setups ](https://connectmq.com/smart-home/)[ ### Fleet Telematics Vehicle tracking, telematics and cold chain ](https://connectmq.com/fleet-logistics/)[ ### Smart Energy Meters, EV chargers, solar and batteries ](https://connectmq.com/energy-utilities/)[ ### Connected Products & Smart Hardware Smart devices you ship to your own customers ](https://connectmq.com/connected-products/)[ ### Connected Robots & Physical AI Robot fleets talking to fleet managers and AI pipelines ](https://connectmq.com/robotics/)[ ### Data Center Monitoring Power, cooling and rack environment ](https://connectmq.com/data-centers/)[ ### Smart City Streetlights, parking, air and waste sensors ](https://connectmq.com/smart-city/)[ ### Smart Agriculture Soil probes, weather stations and irrigation ](https://connectmq.com/smart-agriculture/) Pilot ## Run your next lab on ConnectMQ Start on the public broker with no sign-up, then move the class to a private broker — the Free plan needs no card, Basic gives up to 100 connections, with TLS and its own credentials. [Start for free](https://app.connectmq.com/signup) [See pricing](https://connectmq.com/pricing/) ## Articles [All articles](https://connectmq.com/blog/) IoT Tutorials ### [Free Public MQTT Broker for Testing: Connect to broker.connectmq.com in Minutes](https://connectmq.com/blog/free-public-mqtt-broker/) 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. September 20, 20267 min read IoT Tutorials ### [ESP32 MQTT Tutorial: Publish Sensor Data and Control an LED with Arduino IDE](https://connectmq.com/blog/esp32-mqtt-tutorial/) 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. August 23, 20269 min read MQTT Fundamentals ### [What Is an MQTT Broker? A Beginner's Guide to Publish/Subscribe Messaging](https://connectmq.com/blog/what-is-an-mqtt-broker/) An MQTT broker is the hub that routes every message between IoT devices and apps. Learn publish/subscribe, topics and wildcards, sessions, QoS, retained messages and last will, then try it hands-on in minutes. August 25, 20269 min read