2.3. Communication

In the health-management system's structure, three different types of connections, originating from the mDCS, are distinguished: the connection to the p²Health-Cloud, to the provider-cloud-servers, and to the directly accessible wireless devices (currently considered standards: BLE and Bluetooth Classic). The p²Health-Cloud and the provider-cloud-servers follow the same technical concept. The complexity of the protocol and the data volume are higher with the connection to the p²Health-Cloud.

For connections to the Bluetooth devices, the generic attribute (GATT) profile (for BLE) and the still often used serial port profile (for Bluetooth Classic) are supported. The Bluetooth-device integration follows the standard procedure and will thus not be described here.

Separated connections via appropriated services are used for the API-dependent data exchange with the p²Health-Cloud and the provider-cloud-servers. The latter require the creation of a personal and unique developer account for each client and provider, parallel to the usual user account. Both accounts have a one-to-one relationship. In the authorization process a token is generated, which allows access to the customer's data (Fitbit: OAuth 2.0, time-limited tokens of one or eight hours, refreshing tokens available; Nokia: OAuth 2.0, no time limits for tokens). HTTPS is used for the data transfer from the provider-cloud-servers; the data are anonymized. For the communication between the p²Health-Cloud and the mDCS also the OAuth 2.0 authorization as well as HTTPS and anonymized data are used.

In Figure 4 a simplified sequence diagram, comprising the initialization of the connections and the general control of the data traffic by the mDCS is shown. The MobMedApp realizes the communication management for the individual customer's process on the mDCS. The first step is the establishment of a connection to the p²Health-Cloud to receive all necessary customer-specific configurations of the monitoring process. Dependent on the required data, the MobMedApp establishes the connection to available sensor solutions. The used Bluetooth devices require a periodical data request and a temporary data storage. Data from the provider-cloud servers only need to be requested if the data transfer to the p²Health-Cloud is imminent.

Simplified sequence diagram with the initialization procedure of the connections (between the mDCS, the p²Health-Cloud, and the sensor solutions) and the control of the sensor data traffic.