THE WHATIS.COM WORD-OF-THE-DAY May 7, 2002 optical computer ______________ TODAY'S SPONSOR: VeriSign - The Value of Trust
FREE E-COMMERCE SECURITY GUIDE Is your e-business built on a strong, secure foundation? Find out with VeriSign's FREE White Paper, "Building an E-Commerce Trust Infrastructure. Learn how to authenticate your site to customers, secure your web servers with 128-Bit SSL encryption, and accept secure payments online. Click here: http://WhatIs.com/r/0,,3181,00.htm?VeriSign050702 ______________ TODAY'S WORD: optical computer See our definition with illustration and hyperlinks at http://whatis.techtarget.com/definition/0,,sid9_gci283992,00.html An optical computer is a device that uses visible light or infrared (IR) beams, rather than electric current, to perform digital computations. An electric current flows at only about 10 percent of the speed of light. This limits the rate at which data can be exchanged over long distances, and is one of the factors that led to the evolution of optical fiber. By applying some of the advantages of visible and/or IR networks at the device and component scale, a computer might someday be developed that can perform operations 10 or more times faster than a conventional electronic computer. Visible-light and IR beams, unlike electric currents, pass through each other without interacting. Several (or many) laser beams can be shone so their paths intersect, but there is no interference among the beams, even when they are confined essentially to two dimensions. Electric currents must be guided around each other, and this makes three-dimensional wiring necessary. Thus, an optical computer, besides being much faster than an electronic one, might also be smaller. Some engineers think optical computing will someday be common, but most agree that transitions will occur in specialized areas one at a time. Some optical integrated circuits have been designed and manufactured. (At least one complete, although rather large, computer has been built using optical circuits.) Three-dimensional, full-motion video can be transmitted along a bundle of fibers by breaking the image into voxels (see voxel). Some optical devices can be controlled by electronic currents, even though the impulses carrying the data are visible light or IR. Optical technology has made its most significant inroads in digital communications, where fiber optic data transmission has become commonplace. The ultimate goal is the so-called photonic network, which uses visible and IR energy exclusively between each source and destination. Optical technology is employed in CD-ROM drives and their relatives, laser printers, and most photocopiers and scanners. However, none of these devices are fully optical; all rely to some extent on conventional electronic circuits and components. RELATED TERMS: infrared http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci214039,00.html current http://whatis.techtarget.com/definition/0,,sid9_gci211871,00.html optical fiber http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci212716,00.html laser http://whatis.techtarget.com/definition/0,,sid9_gci214527,00.html voxel http://whatis.techtarget.com/definition/0,,sid9_gci213321,00.html digital http://whatis.techtarget.com/definition/0,,sid9_gci211948,00.html photonic network http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci284009,00.html ______________________ SELECTED LINKS: At the University of Colorado, a functioning optical computer has been built. http://ece-www.colorado.edu/~harry/spoc/spoc.html ABC News provides a news story about "The Light Fantastic." http://abcnews.go.com/sections/tech/DailyNews/photons990521.html NASA describes how optical components can be manufactured in space. http://science.nasa.gov/newhome/headlines/msad18may99_1.htm Although not a recent paper, NTT's Vision for Optical Computers provides more background. http://www.atip.org/public/atip.reports.94/ntt-oc.94.html ______________________ KNOW-IT-ALL CHALLENGE | Encrypting backups This week we challenge you to set some guidelines. When is it appropriate to encrypt backups? When is it not? The best answers will go into a random drawing for a chance to win one of five magic TechTarget baseball caps. Deadline for submittals is midnight EST on Friday, May 10. http://whatis.techtarget.com/content/1,290959,sid9_gci821596,00.html ______________________ QUIZ #25 | Security Attacks Should you really be afraid of a smurf? And exactly what threat does a pulsing zombie pose? They're just two of the sinister computer attacks you need to watch out for. Our latest quiz just may send a shiver down your spine. http://searchsecurity.techtarget.com/sDefinition/0,,sid14_gci813585,00.html ______________________________ .NET INFORMATION CENTER Get up to speed on .NET and what it means for you. Visit our .NET Info Center for SearchVB.com's latest .NET news and development tips. Get one-stop access to the most important resources for understanding Visual Studio.Net direct from Microsoft. http://searchvb.techtarget.com/vsnetHome/0,293828,sid8,00.html ______________________________ RECENT ADDITIONS AND UPDATES [1] proportionality http://whatis.techtarget.com/definition/0,,sid9_gci821576,00.html [2] Serial Storage Architecture http://searchstorage.techtarget.com/sDefinition/0,,sid5_gci821579,00.html [3] boustrophedon http://whatis.techtarget.com/definition/0,,sid9_gci344941,00.html [4] micromovie http://whatis.techtarget.com/definition/0,,sid9_gci820978,00.html [5] Direct Access File System http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci820973,00.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. 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