Universal framework for remote firmware updates of low-power devices

摘要

Remote firmware updates are nowadays an important part of any firmware for embedded devices. In systems with dozens or even hundreds of devices, for example wireless sensor networks, cyber-physical systems, smart systems, etc., reprogramming each device manually just to fix a simple issue would be ineffective. We present a novel multiplatform framework for remote updates of low-power embedded devices. Our approach achieves its multiplatform nature through the availability of standard object files for almost every existing platform. We avoid any alteration of the source code and focus on thorough analysis of the firmware outline and generation of the linker commands. The framework tracks changes in the firmware, improves similarity between various versions and generates a differential file, called delta or patch. Reducing data shared between devices with delta files and minimizing the amount of memory operations improves the energy efficiency of an update. The process reduces the update size by approximately 80% compared to the full firmware transfer and improves over existing differencing solutions variously from 5% to 50%. The framework is designed for battery powered, physically inaccessible low-power devices in heterogeneous systems but can be used for any device connected to any network.