applied cryptography - protocols, algorithms, and source code in c

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Unformatted text preview: f no implementation or analysis of any of these ideas. Wait some years and scan the literature before you trust any of them. Cascade Generators There are two ways to use FCSRs in a cascade generator: — FCSR Cascade. The Gollmann cascade with FCSRs instead of LFSRs. — LFSR/FCSR Cascade. The Gollmann cascade with the generators alternating between LFSRs and FCSRs. FCSR Combining Generators These generators use a variable number of LFSRs and/or FCSRs, and a variety of functions to combine them. The XOR operation destroys the algebraic properties of FCSRs, so it makes sense to use it to combine them. The generator, shown in Figure 17.5, uses a variable number of FCSRs. Its output is the XOR of the outputs of the individual FCSRs. Other generators along similar lines are: — FCSR Parity Generator. All registers are FCSRs and the combining function is XOR. — LFSR/FCSR Parity Generator. Registers are a mix of LFSRs and FCSRs and the combining function is XOR. — FCSR Threshold Generator. All registers are FCSRs and the combining function is the majority function. — LFSR/FCSR Threshold Generator. Registers are a mix of LFSRs and FCSRs and the combining function is the majority function. — FCSR Summation Generator. All registers are FCSRs and the combining function is addition with carry. — LFSR/FCSR Summation Generator. Registers are a mix of LFSRs and FCSRs and the combining function is addition with carry. 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) Go! Keyword 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 T...
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This note was uploaded on 10/18/2010 for the course MATH CS 301 taught by Professor Aliulger during the Fall '10 term at Koç University.

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