Encryption algorithm with 'sponge construction' picked to succeed SHA-2

03.10.2012
Bringing to a close a five-year selection process, the U.S. National Institute of Standards and Technology (NIST) has selected the successor to the encryption algorithm that is used today to secure much of the information on the Internet.

For SHA-3 (Secure Hash Algorithm), NIST has selected Keccak (pronounced "catch-ack"), an algorithm authored by Guido Bertoni, Joan Daemen and Gilles Van Assche of STMicroelectronics, as well as Michaël Peeters of NXP Semiconductors.

NIST had received 63 submissions since putting out an to find a successor to SHA-2. SHA-2 is actually a set of cryptographic hash functions (SHA-224, SHA-256, SHA-384, SHA-512) in the MD (message digest) algorithm design. At that time, some of the SHA-2 algorithms , so NIST set up a competition to find their eventual replacement.

A hash algorithm takes a fingerprint, or signature, of a digital file so that if the content is changed in any way, it will no longer match the hash. It is also nearly impossible to create the same hash fingerprint from a different file. These characteristics can assure that a file has not been tampered with, which is essential for securing electronic documents and online communications against interlopers.

According to NIST, Keccak had a number of appealing traits that made it an obvious choice for SHA-3. For one, it was elegantly designed and constructed in such a way that it could be easily analyzed.

"Depending on the complexity of the algorithm, it may be more or less difficult to do the analysis that gives us confidence in an algorithm. What is elegant about Keccak is that it is a very easy-to-understand design, and so it is easy to build confidence that it is secure," said NIST computer security expert Tim Polk. "Some algorithms have so many moving parts that cryptanalysts don't have confidence that [these parts] won't interact in a way that would cause a problem."