ESP32 MQTT IoT System 📌 Project Overview

This project implements a complete IoT communication system based on MQTT protocol, using an ESP32 as the client device and a Raspberry Pi as the MQTT broker.

The system demonstrates how embedded devices communicate through a lightweight messaging protocol in a real-world scenario.

ESP32 ---> MQTT ---> Raspberry Pi (Local Broker) | | ngrok TCP Tunnel ↓ Subscriber (PC / ESP32)

🚀 Features 📡 ESP32 publishes sensor / user-defined data via MQTT 🖥️ Raspberry Pi acts as a local MQTT broker 🔄 Real-time publish/subscribe communication 🔌 Easy deployment using shell scripts 🔁 Supports basic testing with MQTT CLI tools

🧪 How to Run 1️⃣ Setup MQTT Broker (Raspberry Pi) chmod +x mqtt_setup.sh ./mqtt_setup.sh

2️⃣ Start Broker chmod +x mqtt_start_broker.sh ./start_broker.sh

3️⃣ Test MQTT Communication Open two terminals: Terminal 1: chmod +x mqtt_sub.sh ./mqtt_sub.sh Terminal 2: chmod +x mqtt_pub.sh ./mqtt_pub.sh

4️⃣ Setup ngrok chmod +x ngrok_setup.sh ./ngrok_setup.sh

Add your token: ngrok config add-authtoken YOUR_TOKEN

5️⃣ Start ngrok chmod +x ngrok_start.sh ./ngrok_start.sh You will see: Forwarding tcp://0.tcp.ngrok.io:xxxxx -> localhost:1883

⚠️ Notes ngrok port changes every time Broker must be running before ngrok

6️⃣ Run ESP32 Configure WiFi and broker IP in ESP32 firmware Flash using ESP-IDF: idf.py build idf.py flash monitor

⚠️ Notes // Update broker address with ngrok TCP endpoint .broker.address.uri = "mqtt://0.tcp.ngrok.io:xxxxx"

📈 Future Improvements Add QoS level support Implement MQTT over TLS (Security) Add Web Dashboard (Node-RED / Web UI) Multi-device communication Cloud integration (AWS IoT / EMQX)