Value chain analysis A method developed by Michael E.
Porter to identify possible strategic initiatives by examining
the primary and support activities of an organization that can
add value to a firm’s products or services from a customer
perspective.
VA N SeeValue added network.
Vector-based GIS One of two basic approaches for repre-
sentation and analysis of spatial data in which features in the
landscape are associated with either a point (e.g., customer
address, power pole), a line (e.g., road, river), or a polygon
(e.g., lake, county, zip code area). The vector-based approach is
in widespread use in public administration, public utilities, and
business.
Vertically integrated information system An information
system that serves more than one vertical level in an
organization or an industry, such as a system designed to be used
by an automobile manufacturer and the associated independent
dealers.
View integration A bottom-up approach to detailing an
organization’s data requirements. View integration analyzes each
report, screen, form, and document in the organization and
combines each of these views into one consolidated and consis-
tent picture of all organizational data.
Virtual memory A procedure by which the operating system
switches portions of programs (called pages) between main
memory and DASD so that portions of enough programs are
stored in main memory to enable efficient multiprogramming. To
the user, it appears as though an unlimited amount of main
memory is available, whereas in fact most of each program is
stored in DASD.
Virtual private network (VPN) The equivalent of a private
packet-switched network that has been created using the public
Internet. A VPN provides a moderate data rate at a very reason-
able cost, but the network’s reliability is low; a VPN employs
encryption and other security mechanisms to ensure that only
authorized users can access the network and that the data cannot
be intercepted.
Virtual reality (VR) The use of computer-based systems to
create an environment that seems real to one or more senses
(usually including sight) of the human user or users. Practical
uses of VR include tank crew training for the U.S. Army, the
design of an automobile dashboard and controls, and retail
store layout.
Virtual teams Work teams where members of the team are not
co-located and might not even be in the same time zone or
country. Groupware and other communication tools facilitate
electronic meetings and same time or asynchronous document
sharing.
Virtualization There are two primary flavors of virtualization
in use today: Server virtualization, where a physical server is
split into multiple virtual servers, each of which can be
employed as if it were a stand-alone physical server, thus
reducing the number of physical servers needed in an IT shop
and saving the organization money and space; and desktop
Glossary 689virtualization, where the desktop environment is stored on a
server and only accessed from the desktop, with all applications
run on the server, thus making a thin client a very appropriate
desktop device and saving the organization money. See also
Desktop virtualization, Server virtualization.
Virus A small unit of computer code that invades a computer
program or file. When the invaded program is executed or the file
is opened, the virus makes copies of itself that invade other
programs or files in that computer. It might also erase files or
corrupt programs. Viruses are transmitted from one computer to
another when an invaded computer program or file is transmitted
to another computer. See alsoAntivirus software.
Voice over Internet Protocol (VoIP) SeeInternet telephony.
Voice response unit A computer output method using the
spoken voice to provide a response to the user. This output
method is gaining increasing acceptance as a provider of limited,
tightly programmed computer output, often in conjunction with
touch-tone telephone input.
VoIP SeeInternet telephony.
VPN SeeVirtual private network.
VR SeeVirtual reality.
W3C World Wide Web Consortium, an international consor-
tium of companies involved with the management of the Internet
and the World Wide Web. W3C is the chief standards body for the
Web; among its open standards are Hypertext Transfer Protocol
(HTTP) and Hypertext Markup Language (HTML).
WA N SeeWide area network.
WA P SeeWireless access point.
WAT S SeeWide Area Telephone Service.
Web Shorthand for World Wide Web. SeeWorld Wide Web.
Web 2.0 A phrase that refers to a perceived second generation
of Web-based services that emphasize online collaboration and
sharing among users; such second generation Web-based services
include blogs, wikis, and a variety of social networking applica-
tions such as the very popular MySpace, Facebook, and
Classmates.See alsoBlog, Social networking application, Wiki.
Web browser A software application that enables users to
access and navigate Web sites; the most common Web browsers
are Internet Explorer (Microsoft) and Firefox.
Web services A particular collection of technologies built
around the XML standard of communicating. Web services might
be the means by which SOA services communicate with one
another, but that does not have to be the case. See alsoService-
oriented architecture.
Wi-Fi LAN The most common type of wireless LAN, based on
the IEEE 802.11 family of specifications; Wi-Fi is short for
wireless fidelity. Wi-Fi LANs are rapidly proliferating, with
obvious advantages for people on the move who need access to
the Internet in airports, restaurants, and hotels and on university
campuses. Wi- Fi is also gaining acceptance as a home or neigh-
borhood network. Wi-Fi LANs use the shared Ethernet design
(i.e., logical bus, physical star) and the CSMA/CA Protocol.