THE WHATIS.COM WORD-OF-THE-DAY February 13, 2002 information theory ______________ TODAY'S SPONSOR: VeriSign - The Value of Trust
Secure your servers with 128-bit SSL encryption! Grab your copy of VeriSign's FREE Guide, "Securing Your Web site for Business," and you'll learn everything you need to know about using 128-bit SSL to encrypt your e-commerce transactions, secure your corporate intranets and authenticate your Web sites. 128-bit SSL is serious security for your online business. Get it now! http://ad.doubleclick.net/clk;3902554;5058249;m?http://www.verisign.com/cgi-bin/go.cgi?a=n094473230057000 ______________ TODAY'S WORD: information theory See our definition with hyperlinks at http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci801374,00.html Information theory is a branch of mathematics that overlaps into communications engineering, biology, medical science, sociology, and psychology. The theory is devoted to the discovery and exploration of mathematical laws that govern the behavior of data as it is transferred, stored, or retrieved. In 1948, Claude Shannon, a mathematician at Bell Labs, published a paper entitled A Mathematical Theory of Communication. The paper caught the immediate attention of mathematicians and scientists worldwide. Several disciplines spun off as the result of reactions to this paper, including information theory, coding theory, and the entropy theory of abstract dynamical systems. Whenever data is transmitted, stored, or retrieved, there are a number of variables such as bandwidth, noise, data transfer rate, storage capacity, number of channels, propagation delay, signal-to-noise ratio, accuracy (or error rate), intelligibility, and reliability. In audio systems, additional variables include fidelity and dynamic range. In video systems, image resolution, contrast, color depth, color realism, distortion, and the number of frames per second are significant variables. One of the most important applications of information theory is to determine the optimum system design for a given practical scenario. Information theory is an evolving discipline and continues to generate interest among experimentalists and theorists. RELATED TERMS: Claude Shannon http://whatis.techtarget.com/definition/0,289893,sid9_gci214303,00.html entropy http://whatis.techtarget.com/definition/0,,sid9_gci214429,00.html bandwidth http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci211634,00.html noise http://whatis.techtarget.com/definition/0,,sid9_gci212667,00.html signal-to-noise ratio http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci213018,00.html resolution http://whatis.techtarget.com/definition/0,,sid9_gci212895,00.html ______________________ SELECTED LINKS: Bell Labs provides Claude Shannon's original paper in several downloadable formats. http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html Brown University has a repository of papers about information theory. http://vvv011.northeast.net/~hoffman/shannon/reposit.htm ______________________ QUIZ #20 | Cryptography Get out your whatis.com secret decoder ring and take our latest quiz. Ok, we're kidding about the secret decoder ring, but our latest quiz does test your knowledge about secret messages! http://whatis.techtarget.com/definition/0,,sid9_gci799128,00.html _________________________ STORAGE MAGAZINE EDITORIAL HIGHLIGHTS: MARCH ISSUE Here's a preview of our March topics: ** Strategies to Manage the Explosion of Customer Data. ** Storage Professionals are Hot. (A snapshot of the evolution of the storage profession.) ** How to Make NAS Work with Microsoft Exchange. ** A Guide to Secure SANS. ** Plus how September 11 changed disaster recovery for all of us, and what's been learned about the use of tape, electronic, and disk backup. FREE 42-page storage networking special report with your FREE subscription. Subscribe today at: http://ad.doubleclick.net/clk;3802452;5058249;i?http://www.storagemagazine.com ______________________________ RECENT ADDITIONS AND UPDATES [1] business continuance http://searchstorage.techtarget.com/sDefinition/0,,sid5_gci801381,00.html [2] angstrom http://whatis.techtarget.com/definition/0,,sid9_gci799395,00.html [3] sheepdip http://searchsecurity.techtarget.com/sDefinition/0,,sid14_gci799160,00.html [4] Total Quality Management http://searchebusiness.techtarget.com/sDefinition/0,,sid19_gci799434,00.html [5] Rnext http://searchdomino.techtarget.com/sDefinition/0,,sid4_gci799713,00.html ____________________________________________________________________ ::::::::::::::::::: WHATIS.COM CONTACTS ::::::::::::::::::: LOWELL THING, Site Editor ([EMAIL PROTECTED]) ____________________________________________________________________ MARGARET ROUSE, Assistant Editor ([EMAIL PROTECTED]) ___________________________________________________________________ :::::::::::::::::::: ABOUT THIS NEWSLETTER ::::::::::::::::::::: Created by TechTarget (http://www.techtarget.com) TechTarget - The Most Targeted IT Media Copyright 2002, All Rights Reserved. If you would like to sponsor this or any techtarget newsletter, please contact Gabrielle DeRussy at [EMAIL PROTECTED] If you no longer wish to receive this newsletter simply reply to this message with "REMOVE" in the subject line. Or, visit http://WhatIs.techtarget.com/register and adjust your subscriptions accordingly. If you choose to unsubscribe using our automated processing, you must send the "REMOVE" request from the email account to which this newsletter was delivered. Please allow 24 hours for your "REMOVE" request to be processed.
