A Secure Keyflashing Framework for Access Systems in Highly Mobile Devices

Public Key Cryptography enables for entity authentication protocols based on a platform’s knowledge of other platforms’ public key. This is particularly advantageous for embedded systems, such as FPGA platforms with limited or none read-protected memory resources. For access control to mobile systems, the public key of authorized tokens need to be stored inside the mobile platform. At some point during the platform’s lifetime these might need to be updated in the field due to loss or damage of tokens. This paper proposes a secure scheme for key flashing of Public Keys to highly mobile systems. The main goal of the proposed scheme is the minimization of online dependencies to Trusted Third Parties, certification authorities, or the like to enable for key flashing in remote locations with only minor technical infrastructure. Introducing trusted mediator devices, new tokens can be authorized and later their public key can be flashed into a mobile system on demand.