Software implementation of secure firmware update in IoT concept

Abstract

This paper focuses on a survey of secure firmware update in the Internet of Things, design and description of safe and secure bootloader implementation on RFID UHF reader, encryption with AES-CCM and versioning with use of external backup flash memory device. In the case of problems with HW compatibility or other unexpected errors with new FW version, it is possible to downgrade to previous FW image, including the factory image. Authentication is provided by the UHF RFID service tag used to extract unique initialization vector of the encryption algorithm for each update session. The results show slower update speed with this new upgrade method of approximately 27% compared to older one, using the only AES-CBC algorithm.