Encrypted digital information in a data processing system is decrypted using a key which is a word sequence. The key is generated in a hardware module which is a single chip microprocessor. Individual words of the key word sequence generated by the module are generated as a function of a plurality of...http://www.google.es/patents/US4747139?utm_source=gb-gplus-sharePatente US4747139 - Software security method and systems
