In August 1977, The Stranglers were in the charts with “Something Better Change” and something really was changing, and it something that would change the world forever. This was the month that Martin Gardner, in his Scientific American column, posted a challenge of a method that has stood the test of time: RSA.
It related to the work of R(ivest), A(dleman) and S(hamir) and was a puzzle on their discovery of a method which allowed two keys to be created, where one could encrypt, and the other to decrypt. Their work had been based on a proposal from Whitfield Diffie and Martin Hellman on trapdoor functions that could be used to create the key pair.
In order to explain the RSA concept, Martin’s provided a background the Diffie-Hellman method for which he outlined:
Then in 1975 a new kind of cipher was proposed that radically altered the situation by supplying a new definition of “unbreakable.” a definition that comes from the branch of computer science known as complexity theory. These new ciphers are not absolutely unbreakable in the sense of the one-time pad. but in practice they are unbreakable in a much stronger sense than any cipher previously designed for widespread use. In principle these new ciphers can be broken. but only by computer programs that run for millions of years!
Overall the Diffie-Hellman method has had a good run, but it has struggled in recent years to keep up with the processing power for computers, and the millions of years of running is not quite the case in the modern area, and where the original ciphers could now easily be broken with the simplest of computers within minutes.
With the RSA method, Martin Gardner outlined:
Their work supported by grants from the NSF and the Office of Naval Research. appears in On Digital Signatures and Public-Key Cryptosystems (Technical Memo 82. April. 1977) issued by the Laboratory for Computer Science Massachusetts Institute of Technology 545…