Standards n2

TECHNICAL
N34
Hubbell Premise Wiring • 14 Lord’s Hill Road • Stonington, CT 06378 • Tel: (860) 535-8326 • Fax: (860) 535-8328
Glossary
 Glossary
Service Loop
Excess cable supplied in a channel that is 
stored in a coil for future needs
Signal-to-Noise Ratio (SNR)
The ratio of signal power to noise power 
level in dB. See Noise.
Simplex
Transmission in one direction through a 
single channel.
Singlemode Optical Fiber
A 8-9 micron core optical fiber which 
transmits light only in a single axial direc-
tion, achieving very high bandwidth over 
20 GHz.
Sleeve/Slot
Large circular or rectangular openings 
through walls, ceilings, or floors to allow 
passage of cables, conduit, and innerduct.
Splitter
A passive device used to divide a signal 
into two or more output signals.
ST Connector
A single channel, “straight tip” fiber con-
nector, developed by AT&T, with a bayonet 
style coupling nut, having a 2.5mm ferrule 
diameter.
Star Topology
A network configuration where all work-
stations are cabled individually from a 
horizontal cross-connect (HC), and all 
HC’s are cabled individually from the main 
cross-connect (MC), thus forming a star 
pattern. This is practice is recommended by 
BICSI and TIA.
Surface Raceway
A visible enclosed cable pathway that typi-
cally runs along exposed walls or ceilings. 
Surge Suppression
The isolation and diversion of transient 
voltage surges, which are harmful to elec-
tronic equipment.
T1 Line
A digital transmission line operating at a 
rate of 1.544 Mbps (24 voice channels). 
This is the DS1 level in the TDM digital 
hierarchy. See also DS0, DS1, and TDM.
Tap
An electrical connection into a bus or trunk 
line, such as a drop cable to a workstation.
TBB (Telecommunications Bonding 
Backbone) 
A distributed infrastructure 6AWG or larger 
copper conductor that interconnects all 
TGB’s to the TMGB in a building. See TGB 
and TMGB. 
TCP/IP
Transmission Control Protocol/Internet 
Protocol. A standard client-server network 
connectivity protocol that is supported by 
most LAN/WAN operating systems.
TDR (Time Domain Reflectometer)
An instrument that transmits a signal and 
measures back-reflected signal to charac-
terize faults along a transmission line. See 
also OTDR.
Telecommunications Room (TR)
An enclosed building space for housing 
telecommunications equipment, cable ter-
minations, and cross-connect cabling. A TR 
serves a single floor in a building.
TGB (Telecommunications Grounding 
Busbar)
A pre-drilled solid copper bar that is bond-
ed to the TBB, and serves as the common 
grounding point for electronic equipment 
and cabling hardware within a TR or ER.
TIA (Telecommunications Industry 
Association)
An organization of telecommunications 
industry professionals that publishes stan-
dards jointly with ANSI and EIA, through 
an industry-wide balloting process. 
Tight Buffer Cable
An indoor multi-fiber cable with each indi-
vidual fiber having a 900 micron jacket 
applied tightly over the acrylate coating. 
Tip and Ring
An old telephony term synonymous to “plus 
and minus”. Derived from switchboard 
cord plugs, where the tip wire is positive 
and ring wire is negative.
Terminal
An access node through which Date 
Terminal equipment (DTE) is connected, 
allowing data to flow into or out of a tele-
communications network. 
TMGB (Telecommunications Main 
Grounding Busbar)
A pre-drilled solid copper bar that is 
bonded to the primary grounding electrode 
conductor in the electrical service entrance 
facility. The TBB connects to the TMGB.
Token
A specific combination of bits to be used in 
a LAN to grant transmit privileges through 
a ring network. The token circulates con-
tinuously through the ring.
Token Ring Topology
A closed loop daisy chain network configu-
ration where data traffic must flow through 
adjacent equipment in either direction to 
reach the server.
Topology
The physical or logical arrangement or 
mapping of a telecommunications network, 
such as a bus, star, or ring topology.
Transmitter
An active device that emits a pulsed elec-
tronic or optical signal into a transmission 
media.
TSB (Telecommunications System 
Bulletin)
An interim standards document published 
by the TIA, which describes new specifica-
tions and procedures to be incorporated in 
the next revision of the affected standard. 
Twisted Pair Cable
See Balanced UTP Cable.
USOC (Universal Service Ordering 
Code)
An FCC-governed series of registered jack 
(RJ) wiring configurations that connect the 
customer premises equipment to the public 
network.
UTP (Unshielded Twisted Pair)
See Balanced UTP cable.
VCSEL (Vertical Cavity Surface Emitting 
Laser)
A small laser that emits a coherent beam 
of optical power at 850nm in a vertical 
direction from the active surface. VCSEL’s 
are used for Gigabit Ethernet over multi-
mode fiber.
VLAN (Virtual LAN)
The logical grouping of network devices 
into sub-networks using switching technol-
ogy, to improve data traffic flow or security.
Video Signal
Transmission of moving frames of pictures 
in a frequency range of 1 to 6 MHz.
Video Compression
The conversion of analog video to a digital 
format, which can be transmitted as a T1 
signal at 1.544 Mbps. Higher compression 
can transmit at lower bit rates down to 128 
Kbps. 
Visual Fault Locator
A fiber optic light source that emits high 
power red light at 650nm. Used to illumi-
nate fibers in a cable. A broken fiber will 
emit a red glow through the buffer layer.
Voice Over Internet Protocol (VOIP)
The technology of processing and combin-
ing voice signals with packet transmission 
using TCP/IP. Analog voice signals are con-
verted to packets and merged with internet 
traffic.
WAN (Wide Area Network)
A telecommunications network that extends 
beyond the metropolitan area, and may 
span international distances via satellite or 
undersea cabling.
WDM (Wavelength Division 
Multiplexing)
The combining of multiple optical channels 
at different wavelengths into a single multi-
wavelength channel. WDM increases the 
capacity of a single fiber channel. 
WiFi (Wireless Fidelity)
Synonymous to HiFi, describing audio 
equipment. WiFi is another term to 
describe a wireless LAN, operating under 
the IEEE 802.11 standard at 2.4 GHz.
WLAN (Wireless Local Area Network)
A LAN with no wire infrastructure that oper-
ates on RF transceivers. Typically used for 
rapid deployment in temporary situations. 
WLAN transmission is not as fast as wired 
networks, and is affected by obstructions 
and interference.
Wire Map Test
A measure of continuity of all pin/pair 
combinations in a cabled link or channel.
Work Area (Work station)
The building space where the user interacts 
with telecommunications terminal equip-
ment, which is connected to the work area 
outlet.
Zone Cabling
A cable distribution from the horizontal 
cross connect to an open office area (zone) 
utilizing a consolidation point or MUTOA.