0-9  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z wafer A flat sheet of silicon upon which integrated circuits are built. WAN backbone The part of a WAN that carries the bulk of the traffic. WAN analog interconnecting multiple locations over large geographic areas. waveguide A device that restricts waves to a certain region. wavelength Wavelength is the distance between identical points in the adjacent cycles of a waveform. It is a length measurement, generally stated in nanometers (nm) or in micrometers (mm) when referring to the properties of light. A measure of the color of the light for which the performance of the fiber has been optimized. It is a length stated in nanometers or micrometers. wavelength add/drop multiplexer (WADM) MA go to "OADM." wavelength division multiplexing (WDM) An optical (analog) multiplexing technique used to increase the carrying capacity of a fiber network beyond what can currently be accomplished by time division multiplexing (spanM) techniques. Different wavelengths of light are used to transmit multiple streams of information along a single fiber with minimal interference. DWDM is a specific type of wave division multiplexing (WDM) wherein four or more wavelengths in the 15xx-nanometer EDFA gain region are multiplexed on a single fiber. DWDM has been mainly deployed as a point-to point, static overlay to the optical spanM network to create "virtual" fiber. Thus, DWDM is the precursor to optical networking. DWDM has drastically reduced the cost of transport by reducing the number of electrical regenerators required and sharing a single over multiple signals through the use of EDFAs. wavelength locker A device used to control a laser's wavelength precisely. wavelength translation A function of some OADMs and OXCs whereby a signal entering the network element (NE) on one physical wavelength leaves the NE on a different physical wavelength. This signal could be part of a single light path. NEs available today can do fixed wavelength translation, meaning that the two physical wavelengths used are predetermined and cannot typically be changed without human intervention at the NE. web hosting Theout sourcedd provisioning of infrastructure and/or services necessary to create, maintain, and/or monitor an Internet site. weighted average cost of capital (WACC) The rate of return a business could earn if it chose another investment with equivalent risk, calculated using the weighted average of a firm's cost of debt and classes of equity. wholesaler In a service provider environment, wholesaler refers to the leasing of bandwidth or capacity by one service provider to another. wide area network (WAN) The networking of computers on a large geographic scale (globally, nationwide, in a metropolitan area or across a campus). WANs generally incorporate some sort of high-data-rate carrier or ISP connection, such as frame relay, ISDN, T1 or ATM . wideband code division multiple access (W-CDMA) A 3G technology that increases data transmission rates in GSM systems by using code division multiple access (CDMA) instead of time division multiple access (TDMA). W-CDMA has become the direct sequence (DS) mode in the ITU's 3G specification, which includes the 1x Multi-Carrier mode (1x MC) and 3x Multi-Carrier mode (3x MC). 1x MC (formerly known as cdma2000) and 3x MC comprise the 3G upgrade path for carriers already using CDMA (cdmaOne). window (of fiber) A particular frequency spectrum that passes optical light with minimum attenuation. wireless application protocol (WAP) A carrier-independent, transaction-oriented protocol designed to enable advanced wireless devices allowing the easy transmission of data signals, particularly Internet content, to micro-browsers built into the device's software. WAP version 1.1 was released in June 1999. wireless markup language (WML) A strict Web scripting language that translates HTML language so that WAP-enabled devices can access the Internet and send and receive email wireless transport layer security specification (WTLS) WTLS is a security protocol that implements options for authentication and encryption. It is optimized for use in the mobile environment.