A Cryptography Primer 57 broke a DES key in 22 hours and 15 minutes. Later that year a new form of DES called Triple DES, which encrypted the plaintext in three iterations, was published. It remained in effect until 2002, when it was superseded by AES. Rivest, Shamir, and Adleman (RSA) The release of DES also included the creation and release of Ron Rivest, Adi Shamir, and Leonard Adleman's encryption algorithm (RSA). Rivest, Shamir, and Adleman, based at the Massachusetts Institute of Technology (MIT), publicly described the algorithm in 1977. RSA is the first encryption standard to introduce (to public knowledge) the new concept of digital signing. In 1997 it was revealed through declassification of papers that Clifford Cocks, a British mathematician working for the U.K. Government Communications Headquarters (GCHQ), had, in 1973, written a paper describing this process. Assigned a status of top secret, the work had previously never seen the light of day. Because it was submitted in 1973, the method had been considered unattainable, since computing power at the time could not handle its methods. Advanced Encryption Standard (AES or Rijndael)