International Association
for Cryptologic Research

We report on the development of BlueJay, a

hybrid Rabin-based public key encryption cryptosystem that

is suitable for ultra-lightweight (total 2000-3000 GE) platforms

such as microsensors and RFID authentication tags. The design

is related to authors\' Passerine and the Oren-Feldhofer WIPR

proposals, but is suitable to a wider array of applications.

The encryption mechanism is significantly faster and the

implementation more lightweight than RSA (even with public

exponent 3) and ECC with the same security level. Hardware

implementations of the asymmetric encryption component of

the hybrid cryptosystem require less than a thousand gate

equivalents in addition to the memory storage required for

the payload and public key data. An inexpensive, milliscale

MCU SoC BlueJay implementation is reported and compared

to RSA-AES on the same platform. The private key operation

(not performed by the light-weight device but by the sensor

network base station or a data acquisition reader) has roughly

the same complexity as the RSA private key operation.