glossary of terms for fiber optics

1000BASE-T A recent LAN standard for implementing 1000 Mbps Ethernet on Category 5 cable. See also Gigabit Ethernet.
100BASE-T — The twisted pair version of 100 Mbps Ethernet. Requires Category 5 cabling.
10BASE2 — Also called Thinnet. 10 Mbps Ethernet on thin (RG58) coaxial cable.
10BASE5 — Also called Thicknet.10 Mbps Ethernet on thick coaxial cable.
10BASE-T — 10 Mbps Ethernet on twisted-pair (Category 3) cable.
110 Connector — A popular insulation displacement connector (IDC) used modular jacks, patch panels and cross connects.
3270 (IBM) — A mainframe computer. Originally implemented on RG62 coax. Now generally implemented on UTP cable using baluns.
66 Block — A legacy cross connect system. Similar in function to AMP 110Connect XC.
:: A ::
Adapter — A mechanical termination device designed to align and join fiber optic connections.
AS/400 (IBM) — A midrange computer system. Originally implemented on twinaxial cable. Now generally implemented on UTP cable using baluns.
Attenuation — A term indicating a decrease in power from one point to another. In optical fibers, it is measured in decibels per kilometer at a specified wavelength.
:: B ::
Backboard — Refers to a plywood panel mounted on the wall of a telecom closet.Used to mount the cross connect.
Backbone Cabling – The portion of the cabling that provides connections between communication closets, equipment rooms and entrance facilities.
Balun — A transformer used to attach coaxial or twinaxial equipment to twisted pair cabling.
BNC — A bayonet style coaxial connector.
Bundle — Many individual fibers contained within a single jacket or buffered tubes.
:: C ::
Cable — Designed to provide mechanical and environmental protection to the fibers.
Category 3 — A performance classification for twisted pair cables, connectors and systems. Specified to 16 MHz. Suitable for voice and data applications up to 10 Mbps.
Category 5 — A performance classification for twisted pair cables, connectors and systems. Specified to 100 MHz.Suitable for voice and data applications up to 155 Mbps (possibly 1000 Mbps).
Category 5e — Also called Enhanced Category 5.A performance classification for twisted pair cables, connectors and systems. Specified to 100 MHz. Suitable for voice and data applications up to 1000 Mbps.
Category 6 — A performance classification for twisted pair cables, connectors and systems. Specified up to 250 MHz.
CATV – Cable television systems. Fiber OWL FO610 recommended.
Channel — The entire horizontal cabling system. Everything between the computer and the LAN hub in the telecom closet, excluding the equipment connections.
Coax — Short for coaxial. Single—conductor cables with braided shields. Used in the 80's for data transmission. Now generally replaced with UTP for data. Still used for video.
Connector — A mechanical device used to provide a means for aligning, attaching and achieving continuity between fibers.
Consolidation point — An interconnect device that allows the horizontal cable to be split into two parts. Used for zone cabling.
Core – The center of the fiber optic cable through which light is transmitted.
Cross connect (XC) — Connecting hardware used to patch between two groups of cables (horizontal to backbone, for example). AMP 110Connect XC.
:: D ::
Data rate — The speed, measured in bits per second, that a particular network (or other application) transmits data.
dB (Decibel) — In fiber optics, a logarithmic unit for the ratio of the power that was received over the power that was originally sent. (dB = 10 log, so 10 dB is 10 times more power than 0 dB, 20dB is 100 times more power than 0dB, etc.)
dBµ — Decibel referenced to 1 microwatt.
dBm — Optical power referenced to 1 milliwatt. (0dBm = 1 milliwatt, 10dBm = 10 milliwatts, 20dBm = 100 miliwatts, etc.)
Delay skew — The difference in propagation delay between the slowest and fastest pairs in a cable or system.
Detector — An electronic transducer used in fiber optics for converting optical power to electric current. In fiber optics, usually a photodiode.
Drop — Refers to the horizontal cabling for one work area, as in "The job has 100 drops."
:: E ::
ELFEXT — Equal Level Far End Crosstalk. A measure of FEXT which accounts for the attenuation of the cabling system.
Enhanced Category 5 — Also called Category 5e.A performance classification for twisted pair cables, connectors and systems. Specified to 100 MHz. Suitable for voice and data applications up to 1000 Mbps.
Entrance Facility – Entrance facilities are the pathways where outside services, such as telephone and cable TV enter the building.
Equipment Room — A centralized space for telecommunications equipment that serves the occupants of the building.
Ethernet — The most common network protocol in use. A protocol is a set of rules enabling data communications. Based originally on a bus topology.
:: F ::
F connector — A common coaxial connector used for video applications (CATV).
FEXT — Far End Crosstalk. Unwanted noise coupled onto a receive pair from a transmit pair at the far end of the system.
Frequency — The number of cycles per second of a periodic waveform, usually expressed in Hertz.
:: G ::
Gbps — A data rate. Gigabits per second. A gigabit is one billion bits.
Gigabit Ethernet — Fastest version of Ethernet. Data rate is 1000 Mbps or 1 Gigabit per second.
:: H ::
Horizontal cabling — Includes the work area outlet, distribution cable and connecting hardware in the telecom closet.
Horizontal Cross-Connect — A cross—connect of horizontal cabling to other cabling, e.g., horizontal to backbone cabling.
Hub Network device — usually in the telecom closet, that stations connect to.
:: I :: J :: K ::
IC (Intermediate Cross-Connect) — A cross-connect between the main cross—connect and the horizontal cross-connect in backbone cabling.
IDC Insulation Displacement Connector — A style of connector that slices through the cable insulation to make a connection. Eliminates the need to strip insulation.
IEEE 802.3 — Usually referred to as Ethernet. A networking protocol.
IEEE 802.5 — Usually referred to as token ring. A networking protocol.
IEEE Institute of Electrical and Electronics Engineers — 802 Group develops Local Area Network standards and Metropolitan Area Network standards.
Impedance — The total opposition to the flow of alternating current in a conductor.
Insertion Loss — The loss of power that results from inserting a component, such as a connector or splice, into a previously continuous path.
Interconnection — A connection scheme that provides for the direct connection of a cable to another cable or to an equipment cable without a patch cord or jumper.
Jumper — Usually unjacketed twisted pair wire used to make a cross connection.
Kbps — A data rate. Kilobits, or thousands of bits, per second.
:: L ::
LAN — Local Area Network. Usually confined to one building or even one floor. Large companies may have several LANs connected by an internetwork or backbone network.
Laser — A light source that is almost perfectly coherent and monochromatic. Lasers in fiber optics are used with single mode fiber cable for long distance applications, such as cable TV and telephone. The Fiber OWL Model EO610 is designed to directly measure the high output power of a laser transmitter.
LCD — Acronym for Liquid Crystal Display. Liquid crystals form patterns when polarized. The orientation of the molecules in the liquid are arranged by the meter to form the display.
LED (Light—Emitting Diode) — A semiconductor device that emits light when current is applied. LEDs are commonly used with multimode fiber cables for LAN and premise cabling. Generally, they are not as powerful as a Laser, but are less costly.
Link — The part of the horizontal cabling system between the work area outlet and the telecom closet termination.
:: M ::
MAC Moves Adds and Changes — When data and voice services (to include: outlets and cabling, patching, etc.) of a given location are moved to a new location or removed completely.
Main Cross-Connect — The cross-connect in the main equipment room for connecting entrance cables, backbone cables, and equipment cables.
Mbps — A data rate. Megabits, or millions of bits, per second.
MHz Megahertz — Millions of cycles (Hertz) per second. A frequency or frequency range (bandwidth) through which a cabling system is specified.
Mode — A possible path followed by light rays.
Modular jack — The standard female connector for twisted pair cable. A "telephone jack".
Modular plug — The standard male connector for twisted pair cable. A "telephone plug".
MT-RJ — A small form factor, dual fiber connector.
Multimode Fiber — A type of optical fiber that supports more than one propagating mode. Multimode fiber cables are typically used up to 2000 meters in LAN and premise cabling. The fibers core diameters are normally 62.5m m and 50m m.
Multi-user outlet — A work area outlet designed to support multiple users. Also called multi—user telecommunications outlet assembly or MUTOA.
MUTOA — See multi-user outlet.
:: N :: O ::
NEXT — Near End Crosstalk. The unwanted noise coupled into a device's receive circuit from its transmit circuit.
NIC — Network interface card. Allows a PC to attach to a network.
Node — A device connected to a network.
OTDR (Optical Time Domain Reflectometer) — A meter that evaluates optical fibers based on detecting reflected light. It’s used to measure fiber attenuation, evaluate splice and connector joints, and locate faults.
Outlet — Where the horizontal cabling terminates in the work area.
:: P :: Q ::
Patch cord — A cable assembly with (usually) a plug on each end, used to make a cross connection.
Patch panel — A rack-mountable panel (usually 19" wide) containing connecting hardware. Used to patch between groups of cables and equipment.
PBX — Private Branch Exchange. The premises telephone switch. Handles telecom functions.
Photo detector — An optoelectronic transducer, such as a PIN photodiode or avalanche photodiode.
Photodiode — A semiconductor diode that produces current in response to incident optical power and used as a detector in fiber optics.
Plenum — A chamber that houses environmental air transfer. Plenum—rated cable is required in such locations.
Power sum — A mathematical addition of noise from multiple disturbers. Applied to NEXT and ELFEXT requirements.
Propagation delay — The amount of time it takes a signal to travel through a cable or system.
Propagation delay skew — The difference in propagation delay between the slowest and fastest pairs in a cable or system.
PS ELFEXT — See power sum and ELFEXT.
PS NEXT — See power sum and NEXT.
Punchdown — Refers to IDC connectors and the method used to terminate them.
:: R ::
Rack — Used to mount patch panels, enclosures and equipment in the telecom closet. Usually 19" wide by 7' high.
Receiver – A device that converts optical signals to an electrical signals.
Return loss — A measure of the signal reflected back toward the transmitter as a result of impedance variations in the cabling system.
Riser — Backbone cabling connecting telecom closets situated vertically on separate floors.
RJ11 — A wiring pattern for 6-position modular jacks. Used to refer to the jacks themselves.
RJ21 — A wiring pattern for a 25-pair (AMP CHAMP) connector. Also used to refer to the connectors themselves.
RJ45 — A wiring pattern for8-position modular jacks. Used to refer to the jacks themselves.
:: S ::
SC connector — A duplex optical fiber connector. The standard connector for optical fiber per the 568 cabling standard.
Single Mode Fiber — An optical fiber that supports only one propagation mode. It has much less loss than multimode fiber and is used by telephone and cable TV companies for long distance applications. The core diameter is typically 9m m.
Source — The light emitter, either an LED or laser diode, in a fiber optic link.
Spectral Width — For a light source, the width of wavelengths contained in the output at one half of the wavelength of peak power. Typical spectral widths are 20 to 60 nm for an LED and 2 to 5 nm for a laser diode.
Splice — An interconnection method for joining the ends of two optical fibers in a permanent or semi-permanent fashion.
ST connector — A bayonet style optical fiber connector. An alternate style per the 568 standard.
STP Shielded Twisted Pair — 2-Pair 150 ohm shielded cable.
Switch — A type of network hub. Provides higher bandwidth than shared hubs.
System/3X (IBM) — The predecessor of the AS/400.
:: T :: U :: V ::
T568A and B — The two standard wiring patterns for 8—position modular jacks.
TC (Telecommunications Closet) — An enclosed space for housing telecommunications equipment, cable terminations, and cross—connects. The closet is the recognized cross-connect between the backbone cable and horizontal cabling.
Telco — Short for telecommunications (or telephone company).
Telco connector — Refers to a 25—pair (AMP CHAMP) connector.
Telecom closet — Telecommunications closet. The area of the building that houses the termination of the horizontal cabling. May also contain LAN electronics.
Thicknet — IEEE 10BASE5.10 Mbps Ethernet on thick coaxial cable.
Thinnet — IEEE 10BASE2. 10 Mbps Ethernet on thin (RG58) coaxial cable.
TIA — Telecommunication Industry Association. TIA/EIA-568-A is equivalent to ISO/IEC 11801 in Europe.
Token ring — A networking protocol based on a token-passing ring.
Transmitter — An electronic device, which converts an electrical signal to an optical signal.
Twisted pair cable — Cable made from pairs of wires which have been twisted together.
UTP Unshielded twisted pair cable — Cable made from pairs of wires which have been twisted together.
:: W :: X :: Y :: Z ::
WA (Work Area) — A building space where the occupants interact with telecommunications terminal equipment such as PCs, telephones, and other office equipment.
Wavelength — The distance between the same two points on adjacent waves or the length required for a wave to complete a single cycle.
Wiring closet — See telecom closet.
Work area — Where the users' communications equipment resides. The part of the cabling system between the outlet and the equipment.
Zone cabling — An architectural concept which splits the horizontal cabling into two sections. Eliminates the need to replace the entire horizontal cable in moves, adds and changes.