The Fast Software Encryption 2005 Workshop was the twelfth in a series of annual workshops on
symmetric cryptography sponsored for the fourth year by the International Association for
Cryptologic Research (IACR). The workshop
concentratedonallaspectsoffastprimitivesforsymmetriccryptology including thedesign
cryptanalysisandimplementationofblockandstreamciphersaswell as hash functions and message
authentication codes. The ?rst FSE workshop was held in Cambridge in 1993 followed by Leuven
in 1994 Cambridge in 1996 Haifain1997 Parisin1998 Romein1999 NewYorkin2000 Yokohamain2001
Leuven in 2002 Lund in 2003 and New Delhi in 2004. This year a total of 96 submissions were
received. After an extensive review by the Program Committee 30 submissions were accepted. Two
of these s- missions were merged into a single paper yielding a total of 29 papers accepted
for presentation at the workshop. Also we were very fortunate to have in the programan invited
talk byXuejia Laion Attacks andProtection ofHash Fu- tions and a very entertaining rump session
that Bart Preneel kindly accepted to chair. These proceedings contain the revised versions of
the accepted papers the revised versions were not subsequently checked for correctness.
