Crypto chip / The Codestar module add-on board

The CodeStar module was designed for encryption and decryption of information for personal computers. The board was inserted into a free computer slot and occupied one 8-bit bus slot of a PC, XT, AT class computer. The module was supplied with a floppy disk with files in the Turbo C++ language under the MS-DOS OS. The original CRY 8 customer circuit, based on reliable technology had the entire information encryption and decryption algorithm hidden. This algorithm (Feistel-type algorithm) was developed and manufactured in Switzerland for reliability on a special order basis, together with a semi-custom integrated circuit using CMOS VLSI technology. The order was placed by the Institute of Computer Systems of the Slovak Academy of Sciences (today‘s Institute of Informatics SAV).

The module was used to encrypt and decrypt the user's information or the user's entire file with an original and constantly changing key, it served to protect the user's data from unauthorised handling of the information, it was guaranteed that the information could not be read by an_ unauthorised person who copied the data or the program without consent, it guaranteed access to selected oformation or user programs only through the correctly entered password and ensured the protection of user programs with the identification number assigned to the user module. The advantage of the module was, that it was hidden in the computer reducing the possibility of loss or theft, the key space (the set of all keys) was 2^48 keys, and no additional forms of encryption were needed. This module was used, for example, to encrypt images during CT and MRI scans at the Derer hospital in Bratislava.