UICE: a low-power high-speed cryptographic module for RFID and embedded systems

Since Radio-Frequency Identification (RFID) systems have become commonplace in access control and security applications, the usage and importance of cryptographic co-processors in RFID transponder devices has grown significantly. Improved vehicle security systems, also known as immobilizers, are required due to increased vehicle theft worldwide. Such devices, and embedded systems in general, must provide high security at low cost and low power. In order to overcome proprietary algorithms with respect to the system manufacturers, a new Universal Immobilizer Crypto Engine (UICE) is proposed. This UICE algorithm is tailored to 8-bit microprocessor architectures and is therefore very fast in software and hardware. The dedicated hardware implementation leads to a small gate count, because the registers for input (challenge) and output (response) are shared. The important non-linear function, in this case an 8 × 8 S-Box, may be built as a gate array or small ROM, which has the advantage of flexibility. Several tests - statistical and random-number - have been performed in order to analyze the strength of the algorithm. So far no weakness was found after ten rounds of encryption.