1000Base-LX/FX
Gigabit Ethernet over fibre optic cable
1000Base-T
1000Mbps, All four pairs of Cat6 cable utilized at 250Mbps per pair
100Base-FX
100 Mbps Ethernet data transmissions over Fibre optic cable
100Base-LX
Long wavelength fibre optic transmissions at 100 Mbps.
100Base-SX
Short wavelength fibre optic transmissions at 100 Mbps.
100Base-T2
100 Mbps Ethernet running over two twisted pairs
100Base-T4
Four pairs of Cat3 or better cable. Transmits at 25Mbps on all four pairs.
100Base-TX
100 Mbps Ethernet running over twisted pair copper. Full duplex
10Base-2
Thin Ethernet, called thin net or coax
10Base-5
Thick Ethernet cable capable of data transmissions up to 500 meters.
10BaseT
10 Mbps Ethernet running over twisted pair copper cable
Alien Crosstalk
Crosstalk from an adjacent cable or cables
ANSI
American National Standards Institute.
ASCII
American Standard Code for Information Interchange. Originally a 7 bit code later 8 bit for communication interfaces
Attenuation
Loss of signal strength and integrity over a given length of cable
Bandwidth
The capacity to carry data
Baseband
The raw data is transmitted using the full bandwidth of the cable with no modulation.
BAUD
Number of signal or voltage changes per second. Sometimes relates to Bps but not always.
BNC
Bayonet connector used with RG58 coaxial cable networks. Thin Ethernet
bps
Bits per second
Broadband
The bandwidth of the cable is split into multiple modulated channels. Guard bands are used to separate the channels
Broadcast
To send data to more than one device at a time
Bus Network
A network with all devices sharing one common cable.
Category 1, Cat1
Unshielded Twisted Pair for use as speaker or door bell wire.
Category 2, Cat2
UTP for frequencies up to 1.5Mhz. Used in analogue telephone applications.
Category 3, Cat3
UTP for frequencies up to 16Mhz
Category 4, Cat4
UTP 100 ohm for frequencies up to 20Mbs
Category 5, Cat5
UTP 100 ohm for frequencies up to 100Mbs
Category 5E, Cat5E
Enhanced Cat5. Similar to Cat5 with improved specifications
Category 6,Cat6
Proposed cabling standard to support up to 250 Mhz over UTP. Not yet ratified.
Category 7, Cat7
Proposed cabling standard to support up to 600 Mhz over UTP.
CDDI
Copper Distributed Data Interface as defined by (ANSI X3T12) for 100Mbs token passing over copper twisted pair.
Coax
Coaxial cable with a copper screen carrying unbalanced signals
Collision domain
All the nodes on an Ethernet segment that are affected by data collisions. Switches and bridges break up networks into individual collision domains
Core
Centre of a fibre optic cable
Crosstalk
interference picked up from an adjacent wire pair within the same cable (see also alien crosstalk)
CSMA/CD
Carrier Sense Multiple Access with Collision Detect. A NIC transceiver “listens†to the network before transmission and can detect collisions.
Drop
Single cable outlet
Drop Cable
The cable from the wall socket to the network device, usually a PC or DTE
EIA
Electronics Industry Association in America
EMI
Electro Magnetic Interference. Unwanted noise from a source such as fluorescent lighting and electric motors
Ethernet
A LAN protocol and/or cable. Invented by Rank Xerox
Fast Ethernet
100Mbps
FDDI
Fibre Distributed Data Interface for 100Mbs token passing over Fibre.
Frame Relay
Efficient method of packaging data into frames for transmission over networks
Full duplex
Allows data transmissions in two directions at once. Transmit and receive simultaneously
Gigabit Ethernet
1000Mbps, 1 Billion bits per second over copper cabling
Half Duplex
Single way transmission. Capable of both Transmitting and Receiving but not simultaneously
IEEE
Institute of Electrical & Electronic Engineers
IEEE 802
The IEEE project number dealing with LAN technologies
IEEE 802.3
Physical cabling layer standards for Ethernet
IEEE 802.5
Physical cabling layer standards for Token Ring
Impedance
Measurement of the opposition to the flow of electrons in a cable. The combination of Resistance, Capacitance & Inductance.
Infrastructure
The collection of communication components that together provide support for the distribution of information within a building or campus
Insertion Loss
The attenuation of a signal as it passes through a connector
Intranet
A large private company network often spanning many countries
IP
Internet Protocol. Along with TCP is used to track and deliver data packets over a network
IPX
Internet Packet Exchange. A Novell networking protocol
ISDN
Integrated Digital Network Services.
ISO
International Standards Organization.
ISP
Internet Service Provider. The company who providing a connection to the internet.
Jabber
A transceiver on an Ethernet network that has failed and is transmitting continuously. May have “locked up†the network with constant storms of packets
LAN
Local Area Network
Local Talk
A slow form of LAN linked to AppleTalk network
MAC
Media Access Control.
MAU
Multiple Access Unit. A token ring hub
Media
The physical wire of fibre for the transmission of signals
Miss-Wire
Where the single wires in a UTP cable have been attached to the connector in the wrong sequence.
Mode
Each wave travelling in an optical fibre.
Modem
A device which modulates & demodulates the signals between digital to analogue circuits.
Multi mode
Fibre optic cable thatsupports multiple wavelengths. Can use inexpensive LED light sources.
N Connector
Connectors used for thick Ethernet 10Base-5 cable
NIC
Network Interface Card
Numerical Aperture
The angle a fibre cable will gather light and propagate it down the core.
Packet
A string of bits containing command information, destination and source addresses and data
Patch Cable
The cable connecting the network panel and the switch or hub
Patch panel
An array of connectors in the network cabinet for plugging in patch cords
POTS
Plain Old Telephone System
Premises cabling
The complete cabling infrastructure for the transmission of voice, data and video in a given building.
Protocol
A data transfer mode using Bit codes, Start Stop bits, Parity. Both transmitter and receiver must use the same protocols.
PSN
Public Switched Networks. The telephone system.
Repeater
A device, usually a network hub or switch that recieves and resends the data boosting the signal
Reversed Pairs
The most common miss wire where the single wires in a pair have been reversed.
RFI
Radio Frequency Interference.
Ring Network
Describes a network in a complete ring
RJ11
Registered Jack number 11. Small line plug and socket used on telephone handsets and modem connections.
RJ45
Registered Jack number 45. 8 pin plug and socket used on Ethernet cables
RS232
Robust but outdated signalling protocol using 2 pairs.
SC
Small Connector used for fibre optic terminations
SCSI
Small Computer Systems Interface. Connects peripherals to a computer
Segment
The area of a network that all node can see each other
Shielded
Cable with a braided or foil shield to keep out RFI and EMI.
SNMP
Simple Network Management Protocol. A protocol governing network management and device handling.
Split Pairs
Where the single wires from two different pairs have been swapped. If the same at both ends will not affect short cable transmissions, but will fail over longer distance
ST connector
Straight Tip. A connector for fibre optic terminations
Star network
Network Topology where all devices are attached to a central hub in a star configuration.
STP
Shielded Twisted Pair copper cable
Switch
An Ethernet active repeater which reads MAC addresses and routes data to the individual node or network hub. Switches split up networks into smaller individual collision domains. A switch can route data at wire speed through all it’s ports simultaniously.
TCP
Transmission Control Protocol. Used with IP to track and deliver packets of data over a network.
Terminator
An electrical connector attached to the end of a cable to reduce signal reflections and unwanted noise.
TIA
Telecommunication Industry Association
Token Ring
A network where a single token is passed around a network between computers. A computer must grab and hold onto the token before it can transmit. After transmission it releases the token back onto the network.
Topology
Network architecture, circuit design and transmission protocols
Transceiver
Circuit that transmits and receives data over a network. A NIC contains a transceiver as does a hub and a switch
Twisted Pair
Pairs of 26 AWG wires twisted together the reduce RFI and Crosstalk.
USB
Universal Serial Bus. 12 Mbs connection port
USOC
Universal Service Ordering Codes Cabling system original used in the American telephone systems.
UTP
Unshielded Twisted Pair. 4 twisted pairs in one sheath.
WAN
Wide Area Network