Fiber Optics Illustrated Dictionary - Part 102 docx

Fiber Optics Illustrated Dictionary of the Web, with the exception of DejaNews (now part of Go ogle Groups), which searches newsgroups. Many also have 'specialties' to set them apart from the others. Note that these search engines catalog millions of pages and they are not necessarily up to date. The best search engines seem to have a lag of about three weeks to three months from the time a site is submitted until it is added to the database. See the appendix for a list of major search engines. Web serverA client/server model system on a multi- user network that serves requests for HTML-based Web pages that are part of the World Wide Web. A Web browser is a type of client software that com- municates with the server through HyperText Trans- fer Protocol (HTTP), and displays the information received from the server in the form ofa Web page con- taining a variety of text, graphics, and sound. Most Internet Services Providers have Web servers. See HyperText Transfer Protocol, server, World Wide Web. Web Service Provider WSP. A commercial provider of computer network access to the World Wide Web or to a local Web-based network. Most, although not all, Internet Service Providers (ISPs) provide Web access and often include it in their monthly subscription cost. They mayor may not provide a diskette with a Web client, called a browser. If not, Web browsers are widely available for download, or through friends, as many of them are freely distributable or shareware. Some service providers use proprietary servers and the user can only use the browser provided for this service; others allow users to select the browsers of their choice. See Web browser, Web server. Web site On the World Wide Web, which is a mechanism for viewing many portions of the Internet, there are businesses and individuals who have organized data files in such a way as to provide a virtual community, storefront, library, educational resource, or other form of informational/educational/entertain- ment source for the public or authorized users. When a Web user accesses the site with a computer program called a browser, she or he is presented with various communications media (text, graphics, sound, etc.) available on the site. A Web site is comprised ofa series of related files, managed by a client/server Web system that serves the Web files, most of which are called Web pages, to processes that request them over the network. These files typically consist of text and graphics organized into hypertext relational links through a markup language called HTML. There may also be sound, fonns, Sun Microsystems Java applets, and various scripts that provide additional functionality to the basic HTML layouts. Web sites are as varied as the people who design them. To mention just a few, there are commercial sites promoting products and services; scheduling sites providing listings of television, radio, and other broadcast venues; weather sites enabling lookup of weather conditions almost anywhere in the world; educational sites through which distance education is becoming more and more available; personal sites 1002 journalizing the day-to-day activities of individuals; genealogical sites detailing family histories; and chat sites in which opinions are readily offered and de- bated. See World Wide Web. Web streaming A capability of a Web browser through addition ofa plugin, or which is incorporated directly into more recent browsers, that allows audio or video playback as the data is transmitted to the browser. In older browsers, if the user clicked on a sound or video file, the browser downloaded the sound or video to the local computer from where it was played after the download. More recently, through Web streaming utilities, the audio or video is played as it is received in 'realtime,' albeit sometimes at a lower quality level and with variations due to the connection speed to the Internet. A number of commercial plugins and applications are available to take advantage of Web streaming, ranging from $20 to over $3000. A freely distributable version, called RealVideo, is available from Progres- sive Networks. Web TV See WebTV. Web-Based Enterprise Management WBEM. A distributed management system based on Web technology. WBEM uses a midlevel manager approach, employing HTTP and Web browsers, to provide access to management data and reporting mechanisms. There have been a number of efforts to standardize distributed management, with mixed results so far. WBEM is supported by HMMS, an open standard of the Desktop Management Task Force, and the HyperMedia Management Schema (HMMS) under the aegis of the Internet Engineering Task Force (IETF). WBEM provides a means to extend the system through HMMS and utilizes HyperMedia management Protocol (HMMP) to link HMMS to run over HTTP. Weblock colloq. The slowdown that may occur when trying to access extremely popular sites on the World Wide Web. The Web version of a traffic gridlock, where everything temporarily slows to a halt. Webcast, NetcastA broadcast using the World Wide Web as the communications medium. While traditional Web browsing involves clicking on desired pages, text, and images, and thus 'pulling' the information to the user, Webcasting involves a method of "pushing" the information at the user in the sense that the user's screen is continuously updated without the user having to click the screen or manually request an update (like watching television). Since early browsers did not inherently function this way, it was usually necessary for the consumer to first download additional software to his or her computer. Subse- quent browsers, such as Netscape Netcaster, directly incorporate the push capabilities and can be used in conjunction with Channel Finder, a directory of Web- casting channels. Webcasting is a significant development. It means the advent of digital TV through a computer, with access to a multitude of "channels" on the Internet. When this catches on, TV will probably never be the same, © 2003 by CRC Press LLC particularly since very specialized infonnation, such as stock and finance channels, art and music channels, etc. can be made available through the Web without the major sponsorship that is necessary to par- ticipate on the big broadcast television networks. HDTV-quality push reception can be accessed with a TV set interfaced with a computer peripheral. See Intercast. WebCrawler One of the significant commercial search engines on the Internet, known for its quick simplicity and very cute little spider mascot. Web Crawler was one of the earlier search engines on the Net. http://www.webcrawler.com/ Webhelp Inc. Enhanced 411 Atelephone Directory Assistance service that provides enhanced information services, including movie infonnation, driving instructions, etc. The service is answered by the local carrier, compressed into a digital audio file, routed through a message gateway to an offshore agent who answers the information request. The caller can elect to receive the return information in a number of ways , including hanging up and waiting for a callback or Web-enabled phone message. The company's goal is to make the world of Web information accessible through the telephone. Webmaster Aprofessional who is responsible for a World Wide Web site. A Webmaster 's duties typically include coding, installation, and maintenance of the site and may also include page layout, content deci- sions, and the production of graphics and text. Many individuals have responded to the demand for Web- masters by learning a little bit of layout and HTML and hiring themselves out as professionals, with mixed results. Proper creation, presentation, and maintenance ofa good site, especially a commercially viable site, involve a large number ofprofessional skills including marketing knowhow; writing, edit- ing and proofreading; graphics design and production; Web statistics monitoring, analysis, and reporting. Choose your Webmaster carefully. In fact, you may do best to team up a user-interface and CGI- savvy programmer with a market-savvy artist and writer. HTML skills alone are not sufficient to create good database, point-of-purchase, or shopping cart software, and these may be essential to a business presence on the Web. WebNFS Web Network File System. A proposed specification for aclient/server protocol as an extension to recent versions of the Network File System (NFS). NFS is an RPC-based, platform/transport independent protocol and WebNFS is intended to provide semantic extensions to NFS. It helps make file handles faster and easier to obtain, and may improve transit of firewalls and system scalability. WebNFS clients assume the availability of a WebNFS server registered on port 2049. See Network File System, RFC 1094, RFC 2054, RFC 2055. Website Meta Language WML. An extensible, freely distributed offline HTML-generation toolkit for use by Web designers creating Web sites on Unix systems. WML is written in ANSI C and Perl 5. It is distributed under the GNU General Public License (GPLv2) and may be used free of charge in educational and commercial environments. Webspace Derived from cyberspace, Webspace re- fers to the Web environment, the sum total of the hard- ware, software, people, transmissions, and interactions that comprises the World Wide Web community. WebTV A simple consumer-oriented Web access device that uses a TV as the display. It was purchased in August 1997 from the California-based WebTV company by Microsoft Corporation. Sony Electron- ics, Philips Consumer Electronics, and others have products based on the WebTV technology. Webzine An electronic publication available on the Web, either free or through subscription. WECO See Western Electric Company. Wehnelt interrupterA type ofearly electronic apparatus used in laboratories to provide interruptions ranging from 100 to 1000 per second. The positive side ofa circuit was connected to a platinum elec- trode conducting through a well-insulated primary winding coil. This, in tum, was connected to a lead plate in a dilute solution of sulphuric acid. A tube for circulating water was included to provide cooling. WELL,The The Whole Earth 'Lectronic Link. This Web site is somewhat like a bohemian meeting ground for intellectuals and artists. Established in 1985 by Stewart Brand and Larry Brilliant, the WELL's discussion community patrons include many artists, educators, writers, and high-level technical professionals. http://www.well.com! Werts,Alain (ca. 1940s- )AFrench engineer working for Thomson CSF who proposed the use ofsilica- based fiber optic technologies in L'Onde Electronique, in 1966, but was unable to fmd fund- ing to pursue the idea. Charles Kao's ideas were more widely disseminated and developed and Kao became known as a major pioneer in the field. See Kao, Charles. West Coast Computer Faire A historic meeting place for computer hobbyists, many of them pioneers in the microcomputer field. Established in 1978 by Jim Warren, it was then the largest computer show in the world. West Ford satellites A set ofsatellites launched by the United States beginning in 1961. The pioneering West Ford project launched surfaces into orbit that contained millions of slender copper dipoles to provide a reflective "blanket" around Earth. The first launch attempt was unsuccessful due to a failed ejec- tion, but the second launch, in 1963, demonstrated that communication could be achieved, at least with high-powered ground stations. At that time, concerns were expressed over side effects from certain types ofsatellites and space debris, and since the feasibil- ity of active relays was successfully demonstrated, the project was discontinued. See ECHO satellites. WESTAR The name ofa family of We stem Union communications satellites, WESTAR I was the first U.S. domestic communications satellite, launched in 1972. A WESTAR satellite was launched with the Challenger space shuttle mission in February 1984. 1003 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary Unfortunately, the Payload Assist Modules (PAMs) didn't function correctly; the WESTAR was launched into a lower orbit than had been planned, and it had to be retrieved by the shuttle Discovery some months later. Western Electric Company WECO. Originally established as the Gray & Barton company in 1869 by Elisha Gray and Enos Barton. In 1872 it became known as Western Electric Company and, in thirty years, grew to be one of the world's largest manufacturers. The Graybar Electric Company, Inc. was spun off from WECO in 1925 and is still doing business as an employee-owned distributor of telecommunications products. In 1881, Western Electric Manufacturing Company became Western Electric and acquired exclusive rights to manufacture and provide Bell Equipment. In 1915, Western Electric took over Western Electric Company of Illinois and, in 1925, Western Electric Research laboratories were consolidated with part of AT &T's engineering department to form Bell Tele- phone Laboratories, Inc. See Gray, Elisha; Gray & Barton; telephone history. Western Union, Western Union Telegraph Com- pany Western Union was originally organized as the New York and Mississippi Valley Printing Telegraph Company in 1851 by Hiram Sibley, and named West- ern Union Telegraph Company in 1956 by his business associate Ezra Cornell (cofounder of Cornell University), when it merged with Cornell's New York & Western Union Telegraph Company. Cornell was the largest shareholder for over fifteen years. Western Union installed the first North American transcontinental line in 1861. Sibley traveled to Rus- sia and was offered an opportunity to purchase Alaska on behalfof Western Union, but turned it down, pass- ing on the information and the historic opportunity to the U.S. Government. In 1868, Western Union hired C.F. Varley to evaluate the U.S. telegraph system with the result that he introduced many standards for coordinating the various lines and systems. Western Union acquired the rights to new technology, called duplex telegraphy, in the early 1870s. This enabled two messages to be sent concurrently, one in each direction, over the same wire. In 1873, Western Union entered the international market by a takeover of the International Ocean Tele- graph Company. In 1877, Western Union went into competition with the Bell system, acquiring patents or licensing rights from Edison, Gray, and others, and forming the American Speaking Telephone Company. As West- ern Union had thousands of miles of telegraph cable strung across the country, this posed a very real chal- lenge to the Bell system, and they reacted with a patent infringement lawsuit that was upheld two years later in the Supreme Court. Western Union had a short alliance with the Bell system from 1908, when AT&T gained control of the company, to 1913, when it voluntarily sold it off again to forestall government breakup of the company. 1004 In 1943, the Postal Telegraph Company, founded in 1881, was merged into Western Union. In 1950, Samuel Morse's original telegraph instru- ment was presented by Western Union to the Smith- sonian Institution. Other versions of the Morse telegraph are replicas. In 1970, Western Union acquired TWX ( from AT&T) and merged it with its own Telex system. Western Union International was acquired by MCI Interna- tional in 1982. In the mid-1980s, the world was changing rapidly. Communication through the Internet was catching on, overnight couriers were in heavy competition with the telegraph industry, and divestiture changed the competitive atmosphere of the phone industry. As a result of this and other changes, the 138-year reign of the Western Union Telegraph Company ended in 1989. Western Union Telegraph Company Collection This extensive historical collection was presented by the Western Union Telegraph Company to the Na- tional Museum of American History as a gift in 1971. It consists primarily of manuscripts, telegraphs, and photographs previously housed in the Western Union Museum. A tremendous amount of telegraph history is contained in these archives. See Western Union. Western Union Telegraph Museum A historic re- pository of Western Union documents and photographs established in 1912 by in-house engineer H. W. Drake. By 1930, the collection had its own room at Western Union and historical instruments were being added until the late 1960s, when the materials were warehoused. In 1971, the collection was trans- ferred to the National Museum of American History, then called the National Museum of History and Technology. See Western Union. Westinghouse, George (1846-1914) An American inventor who pioneered many aspects of alternating current (AC) power, generators, and the railway air brake (1868). He also made practical applications from ideas derived from or shared with Nikola Tesla, and had more than one disagreement with Thomas Edison. His light and power system was used in the 1893 Chicago World's Fair, the same year he won the historic contract to develop alternating hydroelectric current from the Niagara Falls. WestNet One of several National Science Founda- tion funded regional TCP/IP networks, WestNet is located in Salt Lake City and serves the states ofAri- zona, Colorado, New Mexico, Utah, and Wyoming. wet cell A basic electricity-providing apparatus employing a positive and negative terminal, each sepa- rately in contact with a liquid electrolyte medium (battery acid is an electrolyte). Wet cells are incon- venient in that the electrolyte tends to evaporate and may spill, so other types of cells have been devised, chief among these, the dry cell, available since the early 1900s. A type of wet cell called an air cell became widely used in phone applications. See air cell, Bunsen cell, dry cell. wetting Adhering a uniform, smooth film 01 ~o\del to a surface, usually a base metal. © 2003 by CRC Press LLC wetting agent 1. A substance which, when applied to a surface, prevents it from repelling wetting liquids to enhance the adhesion of liquids to the surface. 2. An agent that facilitates the smooth, even spread of liquid over a surface. WFS See Woodstock File Server. WFWG Windows For Workgroups. See Windows. WGDTB Working Group on Digital Television Broadcasting. WGm Working Group on Information Highway. A working group of the TSACC. WGS World Geodetic System. A very extensive geo- logic data set, updated every decade or so to take advantage of improved data that can be acquired with improved technologies. Wheatstone, Charles (1802-1875) An English physicist who researched acoustics and invented the concertina. He also experimented with electromagnetic and solar clocks, and developed a speaking machine based on earlier work by W. Kempelen. Like Samuel Morse, he received encouragement and assistance from Joseph Henry, and invented a telegraph that predates the one designed by Morse. In co llabo- ration with W.F. Cooke, Wheatstone's telegraph was operating in 1837 and he may have received information and assistance from an earlier telegraph inventor, Francis Ronalds. In 1840, Wheatstone proposed an underwater cable between England and France. The Wheatstone bridge that bears his name was developed by Samuel Christie and described by Wheatstone in 1843. See Cooke, William Fothergill; polar keying; Ronalds, Francis; telegraph, needle. Wheatstone bridge, resistance bridge A device employing a galvanometer and a group of intercon- nected resistors for measuring resistance against a comparative standard. This tool can be used for de- termining faults in a length of wire, so the entire wire doesn't have to be dug up or pulled out. By creating a balanced bridge through various loop tests, the ap- proximate location of the fault point can be deter- mined. The Wheatstone bridge was developed by Samuel Christie. It is named after Charles Wheatstone because he described it in print in 1843 and often mentioned it in his lectures. See megger. Wheler, Granville (1701-1770) An English cleric and experimenter who collaborated with Stephen Gray in discovering conductors and nonconductors, and demonstrated in the late 1720s that an electrical charge could be conducted through a thread of more than 600 feet in length. In fact, it was found it could be conducted simultaneously over multiple threads. See Gray, Stephen. Whetstone When microprocessors were slow and rudimentary in design, and operating systems and software applications were limited, it was easier to run a few tests to evaluate and compare the relative speeds of various systems. Thus, a number of benchmark tests were devised to measure performance. The Whetstone test was developed in the 1970s by B. Wichmann with an Algol 60 compiler. It is named after the English town where it originated. The Whet- stone monitored the number of floating point operations that could be carried out by a process in one second. Floating point operations (flops) are common in processor-intensive computing applications such as graphics and scientific work. See benchmark, Dhrystone, Rhealstone. Whirlwind A historic, large-scale computing machine developed at MIT in the late 1940s and early 1950s. It is credited as being the first realtime-processing digital computer. It is also significant for in- corporating random access memory in a matrix core memory. White Alice Communications System WACS. A historic communications system installed by AT &T and Western Electric. About two dozen of the stations were installed across the state of Alaska, with the White Alice station located on Pillar Mountain in Kodiak. WACS operated from the mid 1950s until 1979 and was dismantled in 1997. It went through a number of hands during its history, including the u.S. Army and RCA. The system used 5-story-high curved rectangular vertical dishes supported with billboard- style scaffolding. Stations intercommunicated through tropospheric scattering White Book 1. Any book in the set of 1992 ITU-T recommendations. 2. A document that specifies MPEG video and audio file structure, coding, and indexing. Up to 74 minutes of full-motion video can be recorded on a disc. White Book discs can be played on standalone video CD and DVD players and on suitably equipped computer systems. The format was introduced in the early 1990s by JVC, Philips, and other major vendors. See MPEG, Red Book. white noise Human-audible signals that consist ofa spectrum of frequencies more-or-Iess evenly distributed across the range so that no one tone predomi- nates, as in background noise. White noise is sometimes used to create ambience in sound systems and it is used in audio experiments. white pages 1. In most English-speaking countries, the directory portion of residential, or residential and business listings, in the local telephone directory. 2. On the Internet, directories ofindividuals' physi- cal and electronic addresses usually accessible to the public through the World Wide Web. Web white pages can be searched through keywords and are more flex- ible and powerful than standard printed phone listings. You don't have to be using the Internet to be listed in these directories; many are compiled from telephone listings and other public sources of information. See ego surfing, yellow pages. white paper Colloq. A technical document, usually describing research, experimental results, or details ofa technology. White papers and Request for Com- ments documents are two of the primary communications venues used by developers of communications technologies to present and disseminate information about their theories, inventions, and opera- tional observations. White Paper The popular name for a paper titled A Statement of Policy on the Management of Internet Names and Addresses that was issued by the U.S. Department ofCommerce's National Telecommuni- 1005 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary cations and Infonnation Administration (NTIA) in June 1998. This document supported a prior Green Paper call for the establishment of a not- for-profit entity to coordinate Internet domain name administration. This was an important step in the direction ofprivatizing the domain name registration system while still acknowledging the rights of national gov- ernments to coordinate their own country code TLDs. This led to the formation of the Internet Corporation for Assigned Names and Numbers (ICANN). See Green Paper, top level domain. white room, clean room A controlled environment in which dust, smoke, bacteria, and moisture are eliminated or regulated in order to reduce interfer- ence with and contamination of the functioning of the environment. Controlled environments are used in component production, research labs, medical facili- ties, etc. white transmission 1. In an amplitude-modulated transmission of an image, a black transmission means that the greatest divergence in amplitude in the signal represents the black tones, and the narrowest divergence represents the lightest tones (or no tone at all). In white transmission, the opposite is true. 2. In a frequency-modulated transmission, a black transmission means that the lowest frequency corresponds to black and the highest frequency corresponds to white, or no tone, and in a white transmission the opposite relationship is used. The concept applies to image scanners, facsimile machines, photocopiers, etc. whiteboarding Communicating through means of text and graphics drawn on an erasable wall board or large sheets of paper. See whiteboarding, electronic. whiteboarding, electronic 1. An electronic software application in which input from various keyboards and pointers is displayed or projected on a large white screen that resembles an erasable whiteboard. 2. A dedicated computer network display system that enables remote two-way communication of ideas through text and graphics. 3. The conceptual analog ofa whiteboard communication, carried over a computer-based videoconferencing system. The author first saw this demonstrated by SGI with a videoconferenced paint program at a trade show around 1991, in which both participants, in different locations, contributed to the same illustration and text while another window simultaneously showed their faces as they talked to one another. As it was demonstrated, the whiteboarding concept was very broad and could conceivably include collaborative use of any type of software application by two or more participants. This is a powerful concept that goes several steps beyond mere conversation on a videoconferencing system and shows great promise. See au- diographics, telecommuting, videoconferencing, whiteboarding. Whittaker, EdmundTaylor (1873-1956) ABritish mathematician and professor, Whittaker made important contributions to mathematical theory and the in- struction of mathematics. Whittaker served as the secretary of the Royal Astronomical Society from 1901 to 1906. In 1905 he was elected as a Fellow of 1006 the London Royal Society and, in 1906, he became the Astronomer Royal for Ireland and accepted a po- sition as an astronomy professor at the University of Dublin. In 1912 he moved to Edinburgh and worked as a professor there until 1946. Whittaker is known for his work in numerical analysis and applied mathematics as it relates to astronomy. In the context of communications, Whittaker developed amathemati- cal framework for later sampling theories that led to the implementation ofpulse code modulation in digital recording. The Sir Edmund Whittaker Memorial Prize is awarded for published works of high merit in mathematics or mathematical physics. See pulse code modulation, sampling theory. whois An Internet username directory service application that responds to a name query by accessing a central database and returning alisting of users found to match the name or aportion of the name. Whois is based on the WhoIs Protocol (NICNAME) which is an elective proposed Draft Standard of the IETF. See finger, rwhois, RFC 812, RFC 954. wicking The process of drawing a liquid out ofa substance or along a path. Wicking occurs when solder runs along a wire or up underneath an insulating sheath. Diapers and hiking socks are designed to wick moisture away from the skin to prevent irritation. Oil lamps draw oil up through the wick as they bum. Wide Area Augmentation System LAAS. A Glo- bal Positioning System (GPS) augmentation system intended to provide safer, more reliable satellite-based navigation services for aviation. WAAS provides geographically expansive en route and nonprecision approach navigation data which is further used in conjunction with the more precise Local Area Aug- mentation System (LAAS) in specific locations. WAAS meets Category I aviation requirements and encompasses most of North America through ap- proximately 25 ground reference stations. Informa- tion is broadcast through GPS frequencies (1575.42 MHz) to onboard aircraft receivers, improving GPS accuracy to about 7 meters. Further details are available through the Federal Aviation Administration (FAA). See Local Area Augmentation System. http://gps.faa.gov/ wide areadifferential GPS WDGPS. An implementation of the Global Positioning System (GPS) that includes a network ofreference stations that act as data collection sites to receive and preprocess GPS satellite signals. The information is forwarded to a central processing hub that creates correction vectors for each satellite, including clock corrections. WDGPS systems can provide more accurate local positioning information for a variety of industries, including surveying and navigation, particularly aviation, where precise positioning for takeoffs and land- ings is important. See differential GPS, local differential GPS, Global Positioning Service. Wide Area Information Server WAIS. Developed in the early 1990s by Brewster Kahle, WAIS is a powerful search and retrieval system widely used on databases on the Internet. The W AIS URL scheme des- ignates WAIS databases, searches, and individual © 2003 by CRC Press LLC documents available from a WAIS database. WAIS can be accessed on the Web through the following URL schemes: WAIS database wais:/'/<host>:<port>/<database> Specific WAIS search wais://<host>:<port>/<database>?<search> Specific WAIS document wais://<host>:<port>/<database>/<wtype>/<wpath> There are freely distributable and commercial versions ofWAIS available. With the burgeoning information on the Net, WAIS is a tool of some signifi- cance. See RFC 1625. Wide Area Information Server gateway WAIS gateway. A computer used as a "go-between" between incompatible networks or applications to translate WAIS data. wide areanetwork WAN. Unlike LANs, which tend to be directly cabled and thus limited in scope, Wide Area Networks can connect users over broad geo- graphical regions through the use of long-distance transmission technologies, such as telephone and satellite services. WANs are often used to connect LANs with a variety ofarchitectures and protocols. A WAN accomplishes the transmission of various formats through routers or, alternately, through bridges, that are protocol independent in order to connect WANs and LANs. See bridge, Local Area Network, router. Wide Area Network Management Center WANMC. There are a number of centers in different organizations operating under this general department title. This is a central facility that administrates, con- figures, and operates various aspects of wide area networks (WANs) depending upon the needs of the firm and the degree ofcentralization. Wide Area Telephone Services See WArS. wide band channel WBC. In FDDI-II isochronous networks, WBC is the circuit-switching capability. Any bandwidth not allocated to WBCs can be used for other data, such as statistical information about data traffic. See Fiber Distributed Data Interface. wide characters Character codes consisting of two bytes (16 bits), rather than the traditional one byte (8 bits), in order to accommodate a much larger number of characters from different languages. See Unicode. wide open receiver A receiver that is receiving a range of frequencies simultaneously. CB radios and various emergency systems are sometimes set to receive a range oftransmissions at one time. wideband 1. A band wider than that which is necessary for transmitting voice, sometimes called medium-capacity band, in the 64-Kbps to 1.5-Mbps range. 2. A range between narrowband and broadband, typically between about 1.5 Mbps and 45 Mbps. 3. A band with a broad range of frequencies, often multiplexed. See broadband, narrowband. wideband digital cross-connectsystem W-DCS. A digital cross-connect system that accepts avariety of optical signals and is used to terminate SONEr and OS-3 signals. In other systems, it may also cross-connect OS-3/0S-1. W-DCS can be used as a network management mechanism. Switching is carried out at the VT level. See broadband digital cross-connect system. wideband modem A modem designed with a bandwidth (frequency spectrum) capability greater than that of common consumer modems designed to work over basic voice channels. widescreen TV A home theater TV set that supports and can display a video transmission with a 16:9 hori- zontal to vertical picture ratio, as is found in movie theatres. These are the same proportions supported by letter-boxed laserdiscs and videos, those in which none of the original movie imagery is cut offof the sides when it is displayed. The 16:9 ratio is also supported by some of the better consumer camcorders. Widrow, Bernard (ca. 1930- ) An American electrical engineer, professor, and pioneer in the field of adaptive signal processing, systems that learn and adapt their behavior through interactions with their environments. Adaptive signal processing relates to neural networks and has practical applications in high speed networking over traditional wirelines, for example. Widrow was a historical early contributor to the theory of adaptive antennas. He coauthored "Adaptive switching circuits" in 1960. He was awarded the IEEE Alexander Graham Bell Medal in 1986, the IEEE Neural Networks Pioneer Medal in 1991, and the Benjamin Franklin Medal in Electri- cal Engineering in 2001. Wiener, Norbert (1894-1964) An American mathematician who collaborated with Arturo Rosenblueth and a group of scientists from various disciplines in developing many fundamental concepts ofartificial intelligence. He authored Cybernetics: or, Control and Communication in the Animal and the Machine in 1948 and updated it in 1961 to include ideas about self-reproducing machines and self-organizing systems. He also contributed to the fields ofstochastic processes and quantum theory. See neural network. WIG Wireless Interoperability Group. See WAP Forum. wild virus See virus, wild. wildcardA symbol which takes the place of and represents a series ofcharacters, or an unknown quantity or any quantity, usually in a numeric or alphanu- meric context. For example, the asterisk (*) is a wild- card character frequently used in computing applications, especially file management, for representing unknown characters or any characters. Thus, the UNIX shell command rm myfile. * would remove any filename in the current directory beginning with "myfile." and ending in any extension (or no extension). WildList Organization International WOr. An au- thoritative industry inventory ofviruses that are a considered to be athreat to computers in general use, Le., those "in the wild." To put it another way, it lists viruses that spread as aresult of normal computer use by a wide general audience, as opposed to those that 1007 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary are developed, tested, and used in labs. Like so many aspects of the computer industry, the WildList started as a freely distributable list developed by Joe Wells in his garage and has grown, with the help of vol un- teers, to be an important resource for research and testing of antivirus software. See virus. http://www. wildlist.org! WiLL See wireless local loop listing Williams-Kilburn tubeA historic cathode-ray tube- based system used to store information electronically for use with computing machines. The system was developed near the end of World War II by F. Will- iams and T. Kilburn who were associated with the Telecommunications Research Establishment (TRE) in Malvern. The cathode-ray beam was used to display dots and dashes on the surface of the tube representing the binary values. Unlike modem cathode- ray tubes with streamlined housings, the Williams- Kilburn tube (also known as the Williams tube) had a boxy industrial look, like a large metal toilet paper roll with a display surface at one end under which were a few small button-shaped dials. The Williams-Kilburn tube became an important component in the subsequent design of the Small Scale Experimental Machine, a historic computer with randomly accessible prof:am instructions and data stored in "tube memory.' It was also incorporated into the later ffiM 701. See Small Scale Experi- mental Machine. Willis GrahamActof1921 An act that not only rec- ognized AT&T's monopoly in the phone industry, but legitimized it as well. However, 28 years later, the U.S. federal government filed antitrust proceedings against both AT&T and Western Electric. This long process was not settled until 1956 with a consent de- cree. See Modified Final Judgment. WIMWAPIdentityModule. See WAPForum, Wire- less Application Protocol. WIN See Wireless Intelligent Network. Win-OS/2 Microsoft and International Business Machines (IBM) were originally collaborating on an operating system for ffiM's microcomputers which ffiM released as OS/2, but at some point during the project, Microsoft stepped back and began concen- trating on developing their own Windows products. The windowing component of OS/2 and a number of the basic concepts were incorporated into Microsoft's Windows product line. WIN95 See Windows 95. Winchester disk A random access hard disk drive marketed in 1980 by Shugart Associates, founded by Alan Shugart, formerly of International Business Ma- chines (ffiM). Considering that computer users were predominantly using cassette and reel-to-reel tapes to sequentially write and read data up until this time, the hard disk drive was an important improvement as a computer peripheral and is still one of the fore- most storage media. winding n. 1. A conductive path, coupled inductively to a magnetic core or cell, usually made of metal wire. Helical coil windings are used in simple armatures, inductors, and transformers. 2. A structure to enhance 1008 the transmitting or receiving of electromagnetic waves. A type of compact antenna mechanism. Vari- ous types of windings can be found around small spool-like cores in old radio sets. These were used for frequency selection, employing different thick- nesses of wire and winding patterns. Depending upon the purpose of the winding, the wire may be left open or may be sealed in paraffin, rubber, or some other protective material. Winding can be somewhat tedious and exacting. For this reason, windings are sometimes done in sections and winding machines may be used to create the coil. Since the amount of wire that is wound is sometimes critical, the spool on which the wire is wound may be weighed before and after the winding, to check that the desired amount has been used. Boiling the coil in linseed oil was one of the tech- niques used in early fabrication to drive out moisture and provide atight insulating layer. Paraffin and rubber were sometimes also used. See basket winding, coil. winding machine Any machine improvised or designed to facilitate wire windings around various cores for the creation ofarmatures, antennas, frequency tuners, spark coils, and other apparatus that utilize wire windings. Evenly wrapped, tight windings are important in many electronic applications and tedious to wind by hand. Thus, a spinning bobbin, lathe, or specialized winding machine is now typically used to increase speed and precision. Basic Armature Winding Types Type Characteristics ring The two common types are spiral wound (single closed helix) and series-connected wave-wound (see the preceding diagram). drum The two common types are lap and wave, which are similar on bipolar machines, but different on multipolar machines. wave The winding passes along the conductor to the back of the armature once through each conductor. multiplex Two or more independent windings on a single armature. These are more commonly used on generators intended to supply large currents with small voltages. window 1. An opening, entrance, time interval, or opportunity. 2. An opening or transparent material that permits light to penetrate, or permits a viewer to see beyond the structure in which the window is installed. 3. A graphical user interface structure developed at Xerox PARC in the 1970s and incorporated into the Alto computer. It first came into widespread © 2003 by CRC Press LLC use on Macintosh computers in 1984 (it was used also on the Apple Lisa in 1983, but the Lisa never caught on). It contains a group of related infonnation or functions. Most computer interfaces now use similar con- ventions for sizing, scrolling, opening, closing, and iconizing a window. See graphical user interface. 4. In networking, an opportunity, space, or transmissions lull during which infonnation can be sent, processed, or otherwise efficiently handled. System tuning, capacity monitoring, and flow control are all ways of taking advantage of windows. windowing A description for a means of organizing and interacting with graphical user interface (GUn structures called windows. A window is essentially a portal into a portion of the computer's data, visually represented within a bounded entity that can usually be moved around, sized, iconized, or placed in priority overlapping with other windows. There are text windows, graphics windows, sound "windows," and others. When they are moved about a computer screen in order to make them comprehensible and easily accessible, popped to the front, or pushed to the back to bring a relevant window to the front, it's called windowing. Windows A Microsoft Corporation graphical operating environment that works in conjunction with Microsoft's text-oriented MS-DOS (Microsoft Disk Operating System), primarily on Intel platfonns, although a number of Windows emulators for other systems are available and recent versions exist for handheld devices. Windows is descended from user interface concepts developed in the 1970s at the Xerox PARC research lab that were fIrst widely incorporated into microcomputers by Apple Computers, Inc. in the early 1980s. Apple shipped the Lisa computer with a graphical user interface in 1983, shortly before the announce- ment of Windows 1.0, which didn't actually ship until late in 1985. Current versions of Microsoft Win- dows use essentially the same basic concepts as their Xerox-inspired predecessors, including icon and gad- get point-and-click interaction, sizable windows, visually accessed directory structures, and window overlap priority for the active window. The Windows Operating Systems chart describes some of the development of various versions. Windows Application Binary Interface WABI. Windows Application Binary Interface. Software from Sun Microsystems that enables Microsoft Win- dows applications to run on the Solaris desktop system. Thus users can have access to the large library of software available for the Windows operating environment and can run them, along with Solaris applications, on computers installed with Solaris. Windings - Various Types of Windings and Historic Armatures Three types of armature windings are shown here: (1) evolute-wound, (2) barrel-wound, and (3) bastard-wound (a variation on barrel-wound is also shown bottom right). [Cyclopedia of AppliedElectricity, 1908.] This schematic shows one type of ring armature, a wave-woundarmatureconnectedin series. The spac- ing of the wire windings is called pitch. ' [Cyclope- dia of AppliedElectricity, Chicago American School of Correspondence, 1908.} This is the armaturefrom a Westinghouse genera- tor. It is a bastard barrel winding, a type of winding whose end connections are inward and cylindrical, thus shortening the length of the armature parallel to the shaft compared with barrel winding. 1009 © 2003 by CRC Press LLC Fiber Optics Illustrated Dictionary Windows Application Binary Interface server WABIs erver. AMicrosoft Windows application server providing integrated Windows/Solaris options to SPARCstation users running Sun Microsystems' So- laris, Solaris Intel, or an X terminal system. Windows Internet Name Service WINS. A name resolution client/server application that resolves the internal names applied to networked Windows computers to corresponding Internet Protocol (IP) addresses. Windows Open Services Architecture WOSA. A Microsoft Corporation distributed, semi-open, client! server-based architecture first announced in 1992. WOSA is built on a three-level model consisting of service providers, applications programming interfaces for each category of services, and the applications themselves. While the service provider interface (SPI) level is essentially open, the applications programming interfaces (APIs) and service provider interfaces (SPIs) are proprietary to Microsoft. Windows Operating Systems Name Description Windows - Early Versions Originally called Interface Manager, the first version of Windows was developed between 1981 and 1985. Windows 1.0 was officially announced in 1983, not long after the release of Apple's Lisa computer, although it was not commercially distributed until two years later, beginning late in 1985, around the same time the Atari ST and Amiga 1000 shipped with full graphical user interfaces (followed by the Apple IIGS). While these competitors never unseated MS-DOSlWindows as the prevalent operating system, they did give consumers and developers food for comparison and many of the ideas pioneered on the competitive machines were incorporated into later versions of Windows. In addition, the distribution of the Amiga in 1985 provoked a storm of discussion about whether operating systems should be multitasking. Despite the controversy, other platforms gradually began adapting task- switching as an early step toward multitasking. Thus, in 1987, when Microsoft released Windows 2.0, it incorporated some of these ideas, including the capability to open more than one application at a time and to overlap windows. Graphical elements were not yet significant, as on the Macintosh, Amiga, or Atari operating systems. Windows 2.0 was renamed Windows/286 when Windows/386 was released later the same year. The early versions Windows were limited to 640 Kbytes of address space and "16-color" palettes (which were actually eight colors plus the same eight displayed at halfintensity). Windows 3.0/3.1 Windows was greatly enhanced and overhauled between 1987 and 1990 to provide an improved user interface, the capability to support more than 16 colors (8 + 8 at half intensity), and memory addressing beyond 640 Kbytes. The result was released as Windows 3.0. Two years later, in 1992, Windows 3.1 shipped with significant enhancements over 3.0, with scalable fonts, object linking and embedding, and better multimedia capabilities (Multimedia Windows was absorbed into this product). Windows 3.1 became a widely distributed version of the Microsoft graphical user operating environment, popular in the mid-1990s. Windows 3.11 was released as a free upgrade in 1994 to correct some ofthe networking functions of Windows 3.1. Windows 3.1 has, for the most part, been superseded by Windows 95, 98, 2000, and ME, although a sizeable number of corporations continued using it for many years after the release of Windows 95. Windows for Pen Computing 3.1 Although not well known, this version of Windows, specifically designed for pen computers requiring handwriting recognition for the execution of commands, shipped in the spring of 1992. Windows for Workgroups 3.1 This version of Windows, designed for integrated networking and sharing of resources, shipped in 1992, the same year as Windows 3.1. It should be noted that the Macintosh operating system provided file sharing network support off-the-shelfeight years earlier, so Workgroups was not a forerunner in microcomputer networking, but it was a welcome enhancement to corporate users running Windows systems and included network mail capabilities. Windows for Workgroups 3.11 was enhanced with a number of features, the most important being the addition of 32-bit file access. 1010 © 2003 by CRC Press LLC Windows Operating Systems, cont. Name Description Windows 95 Windows 95 was the highly promoted successor to Windows 3.1 and, to some extent, also succeeded Windows for Workgroups. Windows 95 first shipped in the summer of 1995. It did not have the robustness, multiprocessor support, or security features of Windows NT, but it was less expensive, and thus became a popular consumer and small business alternative to the more powerful Windows NT operating system. Windows 95 differed from earlier versions in three important ways. It relegated DOS to secondary status, incorporated multitasking, and fully implemented graphics icons and menus. Thus, it followed the example of the Lisa and Macintosh line of computers (1983) and the Amiga and Atari computers (1985) in embracing the graphical interface ideas pioneered by Xerox PARC researchers in the 1970s. All major desktop computers now had graphical interfaces and most of them have multitasking or, at least, task-switching operating systems. Windows 95 was a strong commercial success and was still being used on many systems six years after its release. Windows 98 The successor to Windows 95, released in June 1998. This version was significant in that it was the first to directly incorporate network browsing into its structure, an important trend and step toward integration with the Internet. The Net was growing as an important economic and communications force at the time 98 was released and Microsoft was seeking ways to facilitate Internet access through its operating system. Windows 98 shipped with Internet Explorer, one of the popular Web browsers competing with Netscape Navigator and OmniWeb. This integration of OS and browser software was a point ofcontention with other software manufacturers, as it was felt that this could lead to a stifling of competition through monopolistic practices. While Microsoft continued to ship Windows 98, the Justice Department investigated various allegations against the company, proceedings that continued for several years while Windows came out in new versions. The controversy became even more heated in 2002 when AOLlTime- Warner, who had acquired Netscape, challenged Microsoft's continued efforts to incorporate Internet Explorer into its as. Windows NT Windows New Technology. A 32-bit multitasking, multithreaded, networking operating system first released in 1993, Windows NT shares many basic features and user interface concepts with Windows 95, but it is more polished, more reliable, more secure, and includes symmetric multiprocessor support. Bill Gates has publicly stated that Windows NT originated as "OS/2 3.0," with development work beginning in 1987 based upon the ffiM/Microsoft collaboration to develop OS/2, with D. Cutler heading the evolution into Windows NT since 1989. Windows NT is favored in development environments, server applications, and corporate networks. Windows NT was designed to run on processors other than just the Intel chips, providing portability to other platforms not well supported by earlier versions of Windows, except in the form of third-party emulators. It was offered in workstation and server versions. Windows NT Advanced Server NTAS An extended version of Windows NT specifically aimed at server applications. WindowsCE Released in 1996, CE was aimed at the growing numbers of handheld computing devices and had a look and feel similar to the desktop Windows systems. Version 3 was released in 2000 along with applications development tools for programmers to build embedded device app lications. Windows 2000 Released early in 2000, this product was in many ways a bridge between Windows 98 and Windows NT. Support for small business networks, encryption, Internet access, and the many other features that users were now demanding were being incorporated into Microsoft operating systems by this time. Windows ME Windows Millenium Edition, released fall 2000. Windows ME was aimed as an economical option for home users. It includes some of the multimedia capabilities that were becoming 1011 © 2003 by CRC Press LLC . cross-connectsystem W-DCS. A digital cross-connect system that accepts avariety of optical signals and is used to terminate SONEr and OS-3 signals. In other systems, it may also cross-connect OS-3/0S-1. W-DCS can be used as a network management mechanism. Switching is carried out at the VT level. See broadband. noise Human-audible signals that consist ofa spectrum of frequencies more-or-Iess evenly distributed across the range so that no one tone predomi- nates, as in background noise. White noise is sometimes used to create ambience in sound systems and it is used in audio experiments. white. a range of frequencies simultaneously. CB radios and various emergency systems are sometimes set to receive a range oftransmissions at one time. wideband 1. A band wider than that which is necessary for transmitting voice, sometimes called medium-capacity band, in the 64-Kbps to 1.5-Mbps range. 2. A range between

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