Maximalist Cryptography and Computation on the WISP UHF RFID Tag

Abstract. With continuous improvements in the efficiency of microelectronics, it is now possible to power a general-purpose microcontroller wirelessly at a reasonable range. Our implementation of RC5-32/12/16 on the WISP UHF RFID tag shows that conventional cryptography is no longer beyond the reach of a general-purpose UHF tag. In this paper, (1) we provide preliminary experimental data on how much computation is available on a TI MSP430F1232 microcontroller-based RFID tag containing approximately 8 KBytes of flash and 256 bytes of RAM, and (2) we show that symmetric cryptography is feasible on an RF-powered, general-purpose RFID tag — providing the first implementation of conventional cryptography on an RF-powered UHF RFID tag as far as we are aware.