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

# Applied cryptography protocols algorithms and source code in c

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Unformatted text preview: ls, 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 Table of Contents Next ----------- The book goes on to discuss the results of various randomness tests on the data. It also suggests how to use the book to find a random number: The lines of the digit table are numbered from 00000 to 19999. In any use of the table, one should first find a random starting position. A common procedure for doing this is to open the book to an unselected page of the digit table and blindly choose a five-digit number; this number with the first digit reduced modulo 2 determines the starting line; the two digits to the right of the initially selected five-digit number are reduced modulo 50 to determine the starting column in the starting line. To guard against the tendency of books to open repeatedly at the same page and the natural tendency of a person to choose a number toward the center of the page: every five-digit number used to determine a starting position should be marked and not used a second time for this purpose. The meat of the book is the “Table of Random Digits.” It lists them in 5-digit groups—“10097 32533 76520 13586...”—50 on a line and 50 lines on a page. The table goes on for 400 pages and, except for a particularly racy section on page 283 which reads “69696,” makes for a boring read. The book also includes a table of 100,000 normal deviates. The interesting thing about the RAND book is not its million random digits, but that they were created before the computer revolution. Many cryptographic algorithms use arbitrary constants—so-called “magic numbers.” Choosing magic numbers from the RAND tables ensures that they haven’t been specially chosen for some nefarious reason. Khafre does this, for example. Using Random Noise The best way to collect a large number of random bits is to tap the n...
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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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