Unformatted text preview: oration [961,721] and Bell Laboratories  examined the operation of the S-boxes. Neither analysis revealed any weaknesses, although both found inexplicable features. The S-boxes had more features in common with a linear transformation than one would expect if they were chosen at random. The Bell Laboratories team stated that the S-boxes may have hidden trapdoors, and the Lexar report concluded with: Structures have been found in DES that were undoubtedly inserted to strengthen the system against certain types of attack. Structures have also been found that appear to weaken the system. On the other hand, this report also warned: ...the problem [of the search for structure in the S-boxes] is complicated by the ability of the human mind to find apparent structure in random data, which is really not structure at all. At the second workshop on DES, the National Security Agency revealed several design criteria behind the S-boxes . This did nothing to quell people’s suspicions, and the debate continued [228,422,714,1506,1551]. Previous Table of Contents Next Products | Contact Us | About Us | Privacy | Ad Info | Home Use of this site is subject to certain Terms & Conditions, Copyright © 1996-2000 EarthWeb Inc. All rights reserved. Reproduction whole or in part in any form or medium without express written permission of EarthWeb is prohibited. Read EarthWeb's privacy statement. To access the contents, click the chapter and section titles. Applied Cryptography, Second Edition: Protocols, Algorthms, and Source Code in C (cloth)
Brief Full Advanced Search Search Tips (Publisher: John Wiley & Sons, Inc.) Author(s): Bruce Schneier ISBN: 0471128457 Publication Date: 01/01/96 Search this book:
Go! Previous Table of Contents Next
----------- Various oddities about the S-boxes appeared in the literature. The last three output bits of the fourth S-box can be derived in the same way as the first by complementing some of the input bits [436,438]. Two different, but...
View Full Document
- Fall '10
- Cryptography, Bruce Schneier, Applied Cryptography, EarthWeb, Search Search Tips