## 2 Related Work  
Healthcare systems are facing increasing strain owing to a growing population and a surge in the number of patients. Accordingly, creating smart healthcare by incorporating current technological advancements into the healthcare system is crucial. Currently, the healthcare sector is facing numerous problems due to chronic diseases and the exponential growth of the population. In recent years, IoT and edge, fog, and cloud computing technologies have been developed to store, analyze, and monitor data quickly and stably. Research is being actively conducted on various methods for monitoring patient conditions using such technologies [20; 21; 22]. For example, IoT-based smart healthcare systems collect patient information from various sensors and medical equipment to enable medical practitioners to monitor patients' conditions in real time. Furthermore, it is designed to quickly diagnose diseases in real time and notify guardians or medical practitioners of emergency situations. A previous study proposed an e-health system for the health monitoring of the elderly based on IoT and fog computing [23]. This system, which was developed using the Mysignals HW V2 platform and an Android application acting as a fog server, can periodically collect physiological parameters of the elderly (pulse, body temperature, electrocardiogram (ECG), SpO2, etc.). Using this Android application, the elderly and their families can track health conditions, communicate with healthcare providers (managers and doctors), and receive recommendations, alerts, and warnings. Another study proposed an IoT-based diabetes device that performs several basic analytical processes and communicates data, with a smartphone or tablet functioning as a portable fog or edge computing device through Bluetooth for fast processing in real time [24]. A remote healthcare service system was also suggested in which a user's ECG, temperature, GPS, and weather data are monitored using IoT, mobile edge computing (MEC), and machine learning technologies [25]. The use of smartphones and tablets has increased in health monitoring applications, in which they are used as mobile computing devices and as fog servers that process data and send it to the cloud [26; 27; 28; 29]. A mobile application was used at to monitor the patient's heart in real time as an application through the pulse rate sensor, which measures the patient's pulse and then sends it to storage in a remote database. This application also sends notifications to the doctor if a problem is discovered in the heartbeat. A mobile application was also used to develop a system for monitoring biosignals at work [30]. It monitors the patient's body temperature, heart rate, and blood pressure values obtained from sensors built into the wearable device and notifies doctors or caregivers in real time if there is a discrepancy in normal thresholds [31]. HealthFog provides healthcare as a lightweight fog service and efficiently manages the data of heart patients coming from different IoT devices [32]. HealthFog provides this service by using the FogBus framework [33] and demonstrates application enablement and engineering simplicity for leveraging fog resources to achieve these goals. As mentioned in this section, numerous studies have been conducted regarding the monitoring of patients' health conditions based on IoT and edge, fog, and cloud computing. Most health condition monitoring systems that use IoT equipment have been extensively studied recently for pulse, SpO2, ECG, and body temperature data. However, there is a lack of research on real-time health management monitoring systems that incorporate the five types of raw data measured by pulse oximeters, which are the most frequently used by medical institutions.