Collaboration & Mobile Cloud-Computing: Using CoAP to Enable Resource-Sharing between Clouds of Mobile Devices

As the number of mobile devices per user increases, the need to connect/combine them grows. Current approaches focus on the use of cloud-hosted backend services which allow file and app-state synchronization but fail in providing true resource sharing among mobile devices. To enable true resource/service sharing, the mobile devices of a single user should be combined into a cloud of cooperating mobile devices. Instead of accessing the resources/services of an individual device, a user should be able to seamlessly access the combined resources/services of his/her device cloud. Enabling seamless access to the resources/services hosted on different mobile devices is therefore a key challenge. Exposing the resources/services of each mobile devices within the user´s device cloud via Restful micro-services, is one possible approach. This paper focusses on the use of the IoT protocol CoAP as an application layer protocol. To minimize the energy costs of communication, it was necessary to replace CoAP´s standard transport protocol (UDP) with BLE 4.1. This paper presents the performance of the CoAP protocol using BLE 4.1 on Android Lollipop.