# An IoT System for Remote Monitoring of Patients at Home
## 2 Related Studies  
In [12; 13; 14; 15], web-based remote PHD management systems for activity monitors, a medication dispenser, and pulse oximeters were proposed and constructed. In terms of communication protocols, ISO/IEEE 11073 and OMA DM (Open Mobile Alliance Data Management) protocols were used to transmit measured data or remote commands. Gateways located between PHDs and the management server transform the ISO/IEEE 11073 messages into OMA DM messages, and vice versa. Biomedical data measured by PHDs were transmitted in an FCFS (First Come, First Served) manner, and there were neither message classification in data scheduling/transmission, nor data security in data access. Clinician focused remote monitoring systems for telehealth can be found in [3; 4; 5; 6; 7; 8; 9]. In the telehealth system shown in [8], wireless wristwatch-based monitoring devices are attached to elderly patientsto continuously collect their temperature and motion data. It was found that the designed health monitoring system can be used for an extended period of time and may help older patients with chronic conditions reside in their own homes for longer. In [3; 5], it was found that tortuosity in movement paths by elderly persons was related to cognitive impairment or contributed to an increased fall prediction. Four sensors were installed at each corner of a gathering place in an assisted living facility, to wirelessly sense the location data of tags attached to participants. The location data were used to calculate movement path variability. Even though the data processing and transmission methods used in these studies were not clearly addressed, it seems that the data were transmitted in an FCFS manner, and there was no message classification in data scheduling/transmission. Data security in data access was not mentioned either. Protocol conversion has been used when there are more than two different communication protocols in a system, or when two systems with different communication protocols need to be connected. In [19], a formal model for protocol conversion was presented. The construction of protocol converters was illustrated also. Protocol conversion between wireless sensors (Lean Transport Protocol) and Web systems (Hyper Text Transfer Protocol) was proposed to extend a Web service oriented architecture to wireless sensors for a Web of Things [20]. In particular, self-description of embedded Web services was proposed through the efficient compression of WSDL documents. Backend IT systems can invoke embedded Web services on sensor nodes and vice versa by providing an open framework for protocol conversion. Protocol conversion between SIP (Session Initiation Protocol) and SOAP (Simple Object Access Protocol) can be found in [21]. This proposes a generic SIP/SOAP gateway that implements message handling and network and storage management while relying on application-specific converters to define session management and message mapping for a specific set of SIP and SOAP communication nodes. Thus far, few studies have proposed protocol conversion between ISO/IEEE 11073 protocol and oneM2M protocol, which we propose in this paper. Security issues for IoT systems or mobile devices have been addressed in many papers [22; 23; 24; 25; 26; 27; 28]. In particular, [PERSON] et al. [23] proposed a game-based model for adaptive security in the IoT, with an emphasis on eHealth applications. For the sake of mobile devices, the tradeoff between security-effectiveness and energy-efficiency to evaluate adaptive security strategies was considered also. Authentication is to identify users to enable services for legitimate users only, and is considered one of the key aspects of security issues. Biometric authentication [25; 26; 27; 28] has been the most popular method for individual identification. Biometric authentication involves the comparison of an input data with stored biometric data to identify a specific user. Fingerprints, face recognition, hand geometry and iris recognition, and ECG are some examples of this type of biometric authentication.