The present invention provides a system for surgery which includes an ultrasonic hand piece having a end-effector, a console having a digital signal processor (DSP) for controlling the hand piece, and a memory disposed in the end-effector. The generator console sends a drive current to drive the hand piece which imparts ultrasonic longitudinal movement to the blade. As the generator console reads the memory, the hand piece is authenticated for use with the generator console if a copyrighted data string is present in the memory. In a particular embodiment, the data string is an encrypted code, where the hand piece is authenticated for use with the console by decoding a corresponding encryption algorithm resident in the generator console and providing a responding data pattern.