Abstract
The Advanced Encryption Standard (AES) is extensively used and is
widely believed to provide security that is more than adequate.
Several other cipher designs have been proposed for use in standards,
and new designs continue to be developed, while consideration of cost
and complexity impels that the number of mandatory-to-implement
ciphers be minimized. This note outlines an approach to the
selection of cryptographic algorithms that best serves the needs of
the users of cryptography: AES should continue in its role as the
mandatory-to-implement cipher, while other cipher designs should be
reviewed with the goal of selecting a single standby cipher. If
future advances in the science of cryptanalysis uncover security
issues with the AES, the standby cipher will be ready for adoption as
its replacement.
read more.............http://tools.ietf.org/html/draft-mcgrew-standby-cipher-00