Description

A device that allows the interconnection of two fiber optic connectors.

Add/Drop Mixers

Asymmetric Digital Subscriber Line. A technology that allows data to be sent over existing copper telephone lines (POTS).  Data rates from 1.5 to 9 Mbps when receiving data ('downstream rate') and from 16 to 640 Kbps when sending data ('upstream rate').

A connector whose 'endface' is angled to achieve better backreflection characteristics, typically -65 dB or better

Asynchronous Transfer Mode is a network standard that specifies fixed length cells to transmit data, voice and video.  ATM is a scalable concept that allows data transfer rates from 51 Mbps to more than 1 Gbps.

A 'measure' of signal loss as light travels down a fiber.  Normally measured in dBs at specified wavelength. (Expressed as dB / km.)

The rate of optical power loss as a function of fiber length.  Measured in decibels per kilometer (dB / km).  Attenuation is specified at -60^o to +85^oC:  Multimode:  850 - 1300 nanometers (nm) and Singlemode:  1310 - 1550 nm.

A 'passive optical device' when installed, intentionally adds loss to a system.

The telecommunication premises cabling that connects entrance facilities, equipment rooms and telecommunications closets.  The 'backbone cabling' is comprised of fiber optic cabling, main and intermediate cross-connects, and entrance facility, equipment room and telecommunications closet terminations.  The 'backbone cabling' may be categorized as 'interbuilding backbone' (building to building cabling) or 'intrabuilding backbone' (a building's internal cabling).

The amount of light reflected back to an optical source by a connector interface.

The amount of light deflected at an angle greater than 90 degrees from its original direction of travel.

A 'measure' of a conductor's information carrying capacity.  Typically, this term is used to specify the modal bandwidth of a multimode fiber. When specifying singlemode fibers, see Dispersion.

The 'minimum curvature radius' allowed before light is lost from an optical fiber.  This characteristic is dependent upon the manufacturer's production capabilities and the type of fiber.

Building-centric local exchange operating companies

Business Local Loop

Bits per second data transfer rate.  If the transfer rate is rated in 'hertz' (cycles) per second, the multiplier is 2x (e.g., when a 100 MHz transfer is rated in bits per second it would be:  200 Mbps).

Multiple fiber cable where each fiber has a Kevlar strength member and is jacketed individually.

A signaling concept that modulates the signal on a carrier before transmission.  The broadband concept allows multiple information signals to be transmitted simultaneously on different carriers.

Coupler designed to operate over two 80 nm pass-bands centered at 1310 nanometers (nm) and 1550 nm simultaneously

See Adapter.  Chassis mounted adapter.

Cable Television

Facility for switching signals among local telephone circuits.

Controlled Environmental Vaults

Communications Industry Researches Inc.

The material surrounding the core of an optical fiber, defined by its low refractive index, which allows for total internal reflection in a fiber.

Competitive Local Exchange Operating companies

Coating

An acryl ate polymer material put on the fiber during the drawing process for protection against the environment and rough handling.

Color Code - Fiber

1.     Blue                     7.     Red 

2.     Orange                8.     Black

3.     Green                  9.     Yellow

4.     Black                 10.     Violet

5.     Slate                  11.     Rose

6.     White                 12.     Aqua

Passive branching device that is used to distribute an optical signal amongst two or more output ports.

Percentage of light in a single output port when compared to the total light exiting all output ports of a coupler.

Customer Premises Equipment

The 'minimum angle' at which light is totally reflective.

Coarse Wave Division Multiplexing

A logarithmic unit of measure used to express the change in magnitude of light in an optic fiber or passive component.

Digital Access Cross-connect Switch

Demultiplexing.

Measure of the amount of light observed at the second input port of a coupler when compared to the initial transmitted light level at another input port

The cause of bandwidth limitations in a fiber.  The diffusion of light caused by the various wavelengths propagating at different speeds along the fiber's length.  1)  Chromatic Dispersion is caused by the differential delay of the various wavelengths of light passing through the fiber.  2)  Modal Dispersion is caused by the deferential optical path lengths in a multimode fiber.

Multiple fiber cable where each fiber is loose, allowing many fibers to fit inside a relatively small diameter cable

Metal frame used to organize the rack mountable components of a fiber management system

Digital Loop Carriers

DSL Access Multiplexers

Dense Wave Division Multiplexing

Modified physical contact polish that provides backreflections of -60 dB or better.

A standardized networking protocol that supports the following transfer rates:  1)  10 Base-T:  10 Mbps;  2)  100 Base-TX:  100 Mbps; and,  3)  Gigabit Ethernet:  1 Gbps.

The amount of light lost between the input of a coupler and the sum of the output ports of the coupler.

Fiber Distributed Data Interface is a 100 Mbps fiber-optic local area network protocol.  FDDI-II is an emerging 1 Gbps protocol for networking streaming class data, audio and video.

A 'rigid tube' used to align the polished end of a fiber in a connector.  Typically made of ceramic, polymer or stainless steel.

A material used in both singlemode and multimode connectors.  Most durable and produces the best performance.

A composite plastic used in some multimode connectors and biconic singlemode connectors. Less expensive than ceramic.

Used only in multimode connectors

A 'thin filament of glass' capable of carrying data in the form of light.  The fiber is comprised of a 'solid core,' the 'cladded outer region' and protective acrylate coating.

A method of organizing cross-connects in a 'data com,' 'telecom' or 'CATV' system.

The transmission of light through optical fibers between two locations to affect communications and/or signaling.

Fiber in the Loop

Fiber Optic Test Procedures as defined by TIA/EIA Publication Series 455.  These test procedures are by the fiber optic industry at large and form the performance foundations for Telcordia Certification.

Fiber to the Building

Fiber to the Curb 

Fiber to the Cabinet

Fiber to the Home

Fiber to the Neighborhood

Fiber to the Office

A method of permanently joining the ends of two optical fibers by locally heating and melting two fibers together to form a single, continuous fiber.

A frequency measurement unit equal to one billion (10⁹) cycles per second.

An optimized multimode fiber design concept that maximizes bandwidth by minimizing 'modal dispersion.'  The core's refractive index is maximized at the center axis and minimized at the outer edge.

A facility where signals are distributed in a cable television system.

A seal designed specifically to minimize the penetration of moisture, humidity and contaminants from a coupler package.

Hybrid Fiber-Coax network

A 'horizontal cable cross-connection point' that connects horizontal cabling to other cabling (e.g., backbone, horizontal, equipment, et cetera).

Incumbent Local Exchange Carriers.  An ILEC is whom most people have as their local telephone company. Typically a 'baby bell,' RBOC.

The measure of the speed of light in a material when referenced the speed of light in a vacuum.

That part of a network that carries data from point to point (i.e., the cable plant or physical layer).  An optimal infrastructure design allows the addition of new and/or improved devices without sacrificing bandwidth or requiring additional cabling.

The additional signal loss that is experienced when a passive fiber optic component is added to the system (e.g., connectors, cable assemblies, couplers, splitters, WDMs et cetera).

A secondary cross-connect that administers and connects the 'backbone cabling' between the main cross-connect and a horizontal cross-connect.

A measure of the ability of a WDM to reject an unwanted wavelength from a given output port.  Particularly, when used as a demultiplexer.

A 'fiber optic cable assembly' that has a connector on both fiber ends.

A DuPont trademarked product used as a jacketing material for fiber optical cables that provides strength and mechanical protection.

A kilometer is the standard unit of length measurement for fiber optics.  A kilometer is 1,000 meters or approximately 3,281 feet.  One foot equals 0.3048 m.

Laser diodes are used to convert data from electrical to optical form (O2E).  Typically, a laser diode's light output has a very narrow range of wavelengths, or narrow spectral width (1 to 2 nanometers (nm)).

A light emitting semiconductor device that is used to transmit light with a typical spectral width of 50 - 60 nanometers (nm) into a fiber in response to an electrical signal.  LEDs convert data from electrical to optical form (O2E).

A 'Local Area Network' that is geographically limited.  Typically used to carry data, voice and video.

The main or centralized portion of the 'cabling backbone' that mechanically connects and administers the connectivity between the 'entrance facilities,' 'equipment rooms,' 'horizontal cross-connects' and 'intermediate cross-connects.'

See Adapter

Megabits per second data transfer rate.  One million bits per second (10⁶ bits / second).