Providing interoperability in Bluetooth mesh with an improved provisioning protocol

Different versions of Bluetooth Low Energy (BLE) have been standardized with point-to-point and broadcast topologies. Recently Bluetooth mesh specification provides BLE with mesh topology, highly demanded by Internet of Things (IoT) and numerous applications such as smart cities or Industry 4.0. Bluetooth mesh emerges as one of the most promising low-power IoT standards, enabling many-to-many device communications and optimising the deployment of large-scale device networks. Our research focuses on addressing the significant real-life problem of interoperability, the integration of devices with different topologies and versions of BLE to permit mesh transmissions. This integration will permit to increase the coverage area, to diminish important drawbacks in communication and power consumption and to save money by reducing the number of new devices. We have implemented and evaluated the Bluetooth mesh and the provisioning procedure, which provides network devices with all the necessary data to communicate with the rest of devices in the mesh network. Moreover, the Lightweight Provisioning, our proposal to improve the provisioning procedure, is presented. Our implementation allows Bluetooth non-mesh devices to be provisioned and to take part in a Bluetooth mesh network, making possible to continue using current devices. Performance was evaluated by a set of experiments across two steps: First, the provisioning time was measured for different configurations, including our proposal. Second, we measured the end-to-end delay and the packet reception rate in the lowest compatible BLE version. This work demonstrates real interoperability among devices with different BLE versions, a low end-to-end delay in a small and medium-scale mesh networks and a high packet reception rate for advertising intervals greater than 100 ms.