There’s new research by Department Computer Science, Universidad Técnica de Machala, Ecuador on Design and Practical Evaluation of a Family of Lightweight Protocols for Heterogeneous Sensing through BLE Beacons in IoT Telemetry Applications.
The researchers explain how standard beacon advertising works and documents the existing iBeacon and Eddystone protocols.
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New protocols, LP4S-6 (for resource-constraint beacons), LP4S-X (for more powerful beacons) and LP4S-J (for beacons able to run complex firmware) are proposed that can be used to allow IoT telemetry systems to discover new nodes and to describe and auto-register the sensors and actuators connected to a beacon.
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The paper describes the resultant JSON, shows how a new protocol can be added to an Eddystone beacon and proves how the new latency and power consumption remain low.
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Note that updating the firmware of a beacon is non-trivial because it requires the implementation of what’s already on the beacon without access to the original source code.