Labels:text | paper | font | black and white | publication | document OCR: words into numbers and then scrambling the digits mathematically. What dawned on Hellman and carried the key would be too expensive. Hellman Diffie was that a class of extraordinarily difficult and Diffie remedied this problem by letting each user place his encryption key in a public file, at the mathematical problems, known as one-way func- same time keeping the decoding procedure a secret. tions, acted like their bank machine. A practical code could be built on them. Users would be able to Since then Ronald Rivest, an MIT computer- list their encoding keys in a directory so that anyone science professor, and his colleagues Adi Shamir and Len Adleman have made the code breaker's job could send them a coded message. Yet only they even more difficult by using a new set of one-way would have ...
