Dedicated IC eases SHA-1 token authentication

Dallas Semiconductor has introduced the DS2705, a SHA-1 authentication master. The device provides the master side of a secure hash algorithm (SHA)-based token authentication scheme and orchestrates the challenge/response sequence. It aims to eliminate hardware and software development of a host implementation.

Authentication with the new device can be configured to initiate upon host demand or automatically when a battery or accessory is inserted into a system. The predetermined SHA-1 challenge-and-response pair is stored in the device's nonvolatile EEPROM, which can be permanently locked to prevent corruption.

Upon completion of the challenge-and-response sequence between the master and token, the pass/fail status is reported on the device's port pins (one pin for pass and one for fail) to signal the charge system and/or drive LEDs.

As all communication between the device and the SHA-1 token product occurs through Dallas Semi's 1-Wire interface, only one contact is needed between the host and battery/accessory. Typical applications for the new device include digital cameras, portable DVD and media players, cradle and accessory chargers, and cellphones/smart phones.

The device is available in an 8 inch micro SOP or micro MAX lead-free package. Prices start at $2.20 for 10,000-piece quantities.