ESP32 IoT Telemetry Node

Note

Project Status: Archived / Completed. This repository is finalized and is no longer actively maintained. It remains public as a portfolio project.

🔍Overview

This project implements a secure, full-stack IoT Edge Node architecture. It captures environmental data (Temperature & Humidity) via an ESP32 and transmits it wirelessly using the MQTT protocol to a containerized backend.

The system is designed with a focus on scalability and security best practices, featuring decoupled credentials, non-blocking I/O, Deep Sleep power optimization, and a Dockerized infrastructure ready for deployment.

🎯Key Features

• Protocol: MQTT (Lightweight Pub/Sub messaging).
• Data Format: JSON Serialization ({"device": "id", "temp": 24.0...}) for interoperability with Cloud services.
• Resilience: Automatic Wi-Fi and MQTT reconnection logic.
• Security: Credentials decoupled via secrets.h (GitOps best practice) and sensitive tokens excluded from version control.
• Energy Efficiency: Deep Sleep mode integration (10s sleep cycle) for battery-powered operation.
• Infrastructure as Code: Full backend stack (Broker + Logic) defined in docker-compose.yml.

📁Project Structure

/ESP32-IoT-Telemetry
├── /backend                    # Server-side configuration
│   ├── /node_red_data          # Logic flows & settings (Pre-configured)
│   └── mosquitto.conf          # MQTT Broker configuration
├── /firmware
│   └── /Edge_Telemetry_Node    # ESP32 C++ Firmware
│       ├── Edge_Telemetry_Node.ino
│       ├── WifiUtils.h
│       └── secrets_example.h
├── docker-compose.yml          # Container orchestration script
└── README.md

⚙️Hardware Requirements

• Microcontroller: ESP32 DevKit V1.
• Sensor: DHT11 (Temperature & Humidity).
• Connection: DHT11 Data Pin connected to GPIO 4.

⬇️Setup & Installation

1. Clone or Download this repository.
2. Configuration:
   • Navigate to /firmware/Edge_Telemetry_Node/.
   • Rename SecretsExample.h to secrets.h.
   • Open secrets.h and enter your Wi-Fi SSID, Password, and MQTT Broker IP.
3. Deploy:
   • Open Edge_Telemetry_Node.ino in Arduino IDE.
   • Install required libraries: PubSubClient and DHT sensor library.
   • Upload the firmware to the ESP32.

🐳Backend Deployment (Docker)

This project includes a fully containerized infrastructure using Docker Compose. It automatically sets up the MQTT Broker and the Logic Layer (Node-RED).

Prerequisites

• Docker Desktop installed.

Quick Start

1. Navigate to the project root directory.
2. Run the stack:

   docker-compose up -d

🚀Future Improvements (Concluded)

The project is finalized. The initial roadmap targets were:

• Deep Sleep mode integration for battery optimization (Implemented).
• Implementation of TLS/SSL (MQTTS) for encrypted communication (Out of scope).
• Integration with a Time Series Database (InfluxDB) and Grafana (Out of scope).

📜Credits & Acknowledgements

• Lead Maintainer: Pablo Rodriguez Jimenez - Finished development (Project Archived).
• Original Co-author: Pedro Alfonso Quiles García - Collaborated on the initial prototype logic for the university course.

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Open Source Project for Educational Purposes