Page 305 - Optical Switching And Networking Handbook

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290 Glossary

rectangular, elliptical, or circular in a cross-section. This type of
waveguide may, under certain conditions, contain a solid or
gaseous dielectric material. In the optical regime, a waveguide
used as a long transmission line consists of a solid dielectric fila-
ment (optical fiber), usually circular in a cross-section. In inte-
grated optical circuits, an optical waveguide may consist of a
thin dielectric film.
Wavelength A measure of the color of the light for which the per-
formance of the fiber has been optimized. It is a length stated in
nanometers (nm) or in micrometers ( m).
Wavelength division multiplexer A passive device that com-
bines light signals with different wavelengths on different fibers
onto a single fiber. The wavelength division demultiplexer per-
forms the reverse function.

Wavelength-Division Multiplexing (WDM) Sending several
signals through one fiber with different wavelengths of light.

Wideband Services requiring 1.5 to 50 Mbps transport capacity.