Unformatted text preview: That’s a billion times the age of the universe. 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:
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----------- While the complexity of an attack is constant (until some cryptanalyst finds a better attack, of course), computing power is anything but. There have been phenomenal advances in computing power during the last half-century and there is no reason to think this trend won’t continue. Many cryptanalytic attacks are perfect for parallel machines: The task can be broken down into billions of tiny pieces and none of the processors need to interact with each other. Pronouncing an algorithm secure simply because it is infeasible to break, given current technology, is dicey at best. Good cryptosystems are designed to be infeasible to break with the computing power that is expected to evolve many years in the future. Historical Terms
Historically, a code refers to a cryptosystem that deals with linguistic units: words, phrases, sentences, and so forth. For example, the word “OCELOT” might be the ciphertext for the entire phrase “TURN LEFT 90 DEGREES,” the word “LOLLIPOP” might be the ciphertext for “TURN RIGHT 90 DEGREES,” and the words “BENT EAR” might be the ciphertext for “HOWITZER.” Codes of this type are not discussed in this book; see [794,795]. Codes are only useful for specialized circumstances. Ciphers are useful for any circumstance. If your code has no entry for “ANTEATERS,” then you can’t say it. You can say anythi...
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