
E:\NIS\con_rd\inc_news.htm
|
|
W Wide area network (WAN)
A geographically distributed network composed of local
area networks (LANs) joined into a single large network using services provided by common
carriers. Wide area networks (WANS) are commonly implemented in enterprise networking
environments in which company offices are in different cities, states, or countries or on
different continents.
WAN technologies were previously limited to expensive
leased lines such as T1 lines, slow packet-switching services such as X.25, cheap but
low-bandwidth solutions such as modems, and dial-up Integrated Services Digital Network
(ISDN) connections, but this has changed considerably in recent years. Frame relay
services provide high-speed packet-switching services that offer more bandwidth than X.25,
and virtual private networks (VPNs) created using Internet Protocol (IP) tunneling
technologies enable companies to securely connect branch offices by using the Internet as
a backbone service. Intranets and extranets provide remote and mobile users with access to
company resources and applications and provide connectivity with business partners and
resellers. Wireless networking technologies allow roaming users to access network
resources by using cell-based technologies. Digital Subscriber Line (DSL) services provide
T1 speeds at much lower costs than dedicated T1 circuits. These and other new technologies
continue to evolve and proliferate, allowing enterprise network administrators to
implement and administer a highly diverse range of WAN solutions.
|