Fast Software Encryption (FSE) 2006 is the 13th in a series of workshops on symmetric cryptography. It has been sponsored for the last ?ve years by the International Association for Cryptologic Research (IACR), and previous FSE workshops have been held around the world: 1993 Cambridge, UK 1994 Leuven, Belgium 1996 Cambridge, UK 1997 Haifa, Israel 1998 Paris, France 1999 Rome, Italy 2000 New York, USA 2001 Yokohama, Japan 2002 Leuven, Belgium 2003 Lund, Sweden 2004 New Delhi, India 2005 Paris, France The FSE workshop is devoted to research on fast and secure primitives for symmetric...