A Secure IoT-Based Real-Time Health Monitoring System with AES Encryption Using MAX30102 Sensor and Firebase Cloud

The proliferation of chronic diseases and the limitations of conventional hospital-centric care have intensified global demand for accessible and secure remote health monitoring solutions. This paper presents the design, implementation, and evaluation of a low-cost, Internet of Things (IoT)-based health monitoring system capable of continuously measuring heart rate and peripheral oxygen saturation (SpO₂) using the MAX30102 pulse oximeter sensor. The system is built around an ESP8266 NodeMCU micr