Kitz Forum

Announcements => Site & Forum Discussion => Topic started by: kitz on March 28, 2009, 01:31:42 PM

Title: Glossary
Post by: kitz on March 28, 2009, 01:31:42 PM
Glossary and Explanation of some of the common terms in use on this site.

A (   B (   C (   D (   E (   F (   G (   H (   I (   J (   K (   L (   M (   N (   O (   P (   Q (   R (   S (   T (   U (   V (   W (   X (   Y (   Z (   0-9 ( 
Title: Glossary - A
Post by: kitz on March 28, 2009, 01:44:20 PM
AAL5 - ATM Adaption Layer 5 [ITU.I363-5.1996]

ACK - Acknowledgement.  Control code used to indicate receipt of data from a remote computer.

ADSL - Asymmetric Digital Subscriber Line

AFAIK - As Far As I Know

ATM - Asynchronous Transfer Mode - More info on the ATM Backhaul ( & ATM packets (

Attenuation - A measurement indicating the reduction of signal strength.  In relation to adsl this figure may also be referred to as loop loss and give an approximate indication of the length of your line.  More info from ~ What is attenuation (

ATU-C - ADSL Transmission Unit - Central.  The adsl device in the local  exchange. eg DSLAM or MSAN.

ATU-R - ADSL Transmission Unit - Remote.  The adsl in the home/office. eg adsl modem or router.

AUP - Acceptable Usage Policy.  Terms laid out by your ISP defining acceptable use of your connection.
Title: Glossary - B
Post by: kitz on March 28, 2009, 01:59:46 PM
bps - bits per second. Used to indicate a measurement of speed.  Denoted by a small b

Bps - Bytes per second. Measurement of data transfer speed.  There are 8 bits in a Byte.  Denoted by a capital B and may also be displayed as B/Sec.

BER - Bit Error Rate.

bit - Binary Digit.

BPL - Broadband over Power Lines.

bRAS - Broadband Remote Access Server - A piece of hardware at a remote location, although collectively it may be used to describe a location of many Remote Access Servers and an important location from where your adsl is configured.  More information RAS (

bRAS profile - Broadband Remote Access Server Profile.  Profile information about your line, detailed information about bRAS and IP profile (

BSoD - Blue Screen of Death.

BT - Block Terminal.  Small box often installed in the home to join telephone wires.

BT - British Telecom.  UK's major telephone network supplier.  Split into several distinct sections. More info about the BT Groups (

BTo - British Telecom Openreach division.  - Responsible for the telephone access network and its maintenance,  such as your telephone line from the home to the exchange.

BTr - British Telecom Retail division - Seller of BT services to the general public.  Who we pay our telephone bill to. BT Internet/ BT Broadband also come under the BT retail division.

BTw - British Telecom Wholesale division - Provides network services to telecommunication companies such as our ISP.  BT adsl equipment is maintained & provided by BT Wholesale and they are responsible for such things like the DSLAM in the exchange, the RAS, and the BT backhaul to ISPs.

BTDT(GTS) - Been There Done That (Got the T Shirt)

BTW - By The Way.

Byte - 8 bits.
Title: Glossary - C
Post by: kitz on March 28, 2009, 02:25:12 PM
CBC - Capacity Based Charging.  BT wholesale method of charging ISPs based on the amount of capacity of their Central Pipes - More information CBC (

CGI - Common Gateway Interface.  A webserver interface allowing the transfer of data between the webserver and remote computer.  CGI scripts allow dynamic interaction between a user and the server.

CGI - Computer Generated Imagery.

CHAP - Challenge Handshake Authentication Protocol. A protocol used on servers to validate the identity of remote clients. Commonly used by ISPs to validate customers logging on to the service.

CLI - Command Line Interface. - A method which allows interaction with a computer (or routers) operating system by issuing certain commands.

CLI - Caller Line Identification - Facility which allows customers to see who is calling before they answer the phone.

Colossus - BTw's Main Internet Backbone.  More info on Colossus IP Network (

CP - Consumer Products - BT speak for products sold to the general public.

CPA - Call Routing Apparatus (BT).

CPE - Customer Premises Equipment - BT speak for equipment in your home such as your router or telephone device.

CPU - Central Processing Unit - Computer hardware which carries out the data processing.

CRC - Cyclic Redundancy Check. 

CRC Error - Cyclic Redundancy Check Error - In relation to adsl, when your router has detected an error or lost packet.   More information CRC (

CSC - Customer Support (or Service) Centre for an ISP.

CSE - Customer Service Engineer.

CVLAN - Customer Virtual LAN.

CWDM - Coarse Wavelength Division Multiplexing.

CWSS - Copper Wideband Serving Section (BT).
Title: Glossary - D
Post by: kitz on March 28, 2009, 02:45:50 PM
DAC - Digital To Analog Converter.

DACS - Digital Access Carrier Systems. - ADSL will not work on DACed lines.

Data Rate - An indication of your throughput (or real) speed.

DataStream - Type of adsl where the ISP rents VP bandwidth at the local exchange from BT Wholesale.  For more info see Datastream (

DCoE - Diagnostic Centre of Excellence. An Openreach resource, available to Field Technicians and other members of staff.

DECT -  Digital Enhanced Cordless Telecommunications

DHCP - Dynamic Host Configuration Protocol.  Method of automatically assigning IP addresses to network equipment.

DMT - Discrete Multi Tone Technology.  A method of converting digital data into frequencies that can be carried over the telephone line.  More info on DMT (

DLM - Dynamic Line Management.  BT Wholesale's method of managing ADSL profiles.  Detailed information on BTw's DLM system ( Other LLU providers may have their own DLM system.

DNS - Domain Name System.  A method of converting human readable domain names into an IP address that can be understood by a computer. eg converting a web url such as into the IP address of the server where the website is held.

DNS - Domain Name Server.  A server which holds a list of DNS names to IP addresses.

DoS - Denial of Service.

DOS - Disk Operating System.

DP - Distribution Point. (BT)

DPI - Dots Per Inch.

DSL - Digital Subscriber Line - Broadband technology over the local telephone network.

DSLAM - Digital Subscriber Line Access Multiplexer.  Equipment usually at the local telephone exchange responsible for maintaining your adsl connection.
For detailed information see - DSLAM (

DSLMax - BT Wholesale's offering of 'up to 8Mbps' speeds.  More information : What is DSL Max ( and How Max DSL works (

D/W - Drop Wire (BT).

DWDM - Dense Wavelength Division Multiplexing.
Title: Glossary - E
Post by: roseway on March 28, 2009, 03:18:47 PM
EDO - Extended Data Out. A type of random access memory (RAM).

EEPROM - Electronically-Erasable Programmable Read-Only Memory - A type of non-volatile memory used for storing small quantities of data, which will not be lost when the power is removed. For larger quantities of data, flash memory is used.

EIDE - Enhanced IDE. An improved parallel disk interface. Now being replaced by SATA, a serial interface.

EOT - End Of Thread (meaning end of discussion).

EPROM - Electronically Programmable Read-Only Memory - A type of memory used for permanent storage of small amounts of data.

ESF - Exchange Service Facility - BT term.

Ethernet - Method of transfering data in a LAN (Local Area Network). Special IP addresses are reserved for LAN routing (eg -

EU - End User. - BT and ISP term to describe the likes of you and me.

EULA - End User Licence Agreement.

EXE - Executable file type used in Windows.
Title: Glossary - F
Post by: roseway on March 28, 2009, 03:49:44 PM
FAT - File Allocation Table. A file system used in DOS and early versions of Windows. Still widely used in its FAT32 version for USB flash drives and for disk partitions which are to be shared with other operating systems.

FAQ - Frequently Asked Questions.

FDD - Floppy Disk Drive.

FEC - Forward Error Correction. A method of transmitting data with extra information included, which can be used at the receiving end to correct errors which have occurred in transmission. This can speed up transmission over lines which are subject to errors, by avoiding the need to frequently retransmit packets of data. See ADSL Error Correction. (

Femtocell - Mobile Cellular base station that allows mobile phone coverage over the broadband network.

FJ - Faults Jointer (BT Term).

FMPF - Full Metallic Path Facility.  Type of LLU ( provision where both the voice line and adsl is provisioned by a Telco other than BT.  Also known as Fully Unbundled.

FNF - Fault Not Found (BT Term). When a condition or a reported problem has been verified by a Test System OR directly observed by BT people and subsequently the cause of the condition or problem cannot be found.

FT - Field Terminal (BT)

FTP - First Terminating Point (BT)

FTP - File Transfer Protocol.  A  method of transferring data and files over a network or the Internet.

FTTC, FTTH, FTTP - Fibre To The Cabinet, Fibre To The Home, Fibre To The Premises. The use of high-speed fibre optic cable to connect part or all of the way from the exchange to the user.
Title: Glossary - G
Post by: roseway on March 28, 2009, 04:40:42 PM
Gb - Gigabit. 1000 or 1024 megabits.

GB - Gigabyte. 1000 or 1024 megabytes.

GDI - Graphics Device Interface. The graphics part of Windows.

GIF - Graphics Interface Format. A commonly used format for storing bitmapped graphics. GIF only supports up to 256 colours, so is not suitable for photographs. But it supports animation, so is very useful for small moving pictures (such as forum smilies).

GPON - Gigabit Passive Optical Network.

GPU - Graphics Processing Unit. Commonly referred to as the graphics card in a PC, but is often incorporated into the motherboard.

GUI - Graphical User Interface. The familiar operating system interface which uses a graphical display and can be operated by various input devices such as keyboard, mouse, trackball, etc.
Title: Glossary - H
Post by: roseway on March 28, 2009, 06:53:04 PM
HAL - Hardware Abstraction Layer. The part of an operating system which interfaces with the hardware.

HDD - Hard Disk Drive.

HEC - Header Error Control/Correction - More info Error correction - HEC (

HF - High Frequency.

HR Fault - High Resistance / High Open Fault.  Usually caused by corroded joint or cable.  See ~ adsl only works when the phone is being used  ( more info.

HTML - HyperText Markup Language. The original (and still used) language of websites.

HTTP - HyperText Transfer Protocol. The protocol which is used for connecting sites on the World Wide Web (WWW).

Hz - Hertz. A measure of frequency, equal to cycles per second.
Title: Glossary - I
Post by: roseway on March 28, 2009, 07:29:17 PM
i18n - Internationalisation (the first and last letters of the word, with 18 letters in between).

IANAE - I Am Not An Expert.

IANAL - I Am Not A Lawyer.

IBM - International Business Machines. One of the largest and most influential computing companies in the world.

IC - Integrated circuit ('silicon chip').

ICB - Incoming Calls Barred (BT).

ICD - Internal Cable Distribution. (BT)

ICMP - Internet Control Message Protocol. One of the core internet protocols, mainly used in networks to send error messages, but also used by ping and traceroute / tracert.

IDC - Insulation Displacement Connector

IDE - Integrated Development Environment. An 'everything in one place' environment for software development.

IDE - Integrated Drive Electronics. Hardware included in disk drives to standardise the interface to the computer.

IE - Internet Explorer. Microsoft's browser, which is included with Windows.

IM - Instant Messaging. A real-time medium for exchanging text messages over a network.

IMHO - In My Honest Opinion

IMHO - In My Humble Opinion

IP - Internet Protocol. One of the original core protocols of the internet, often combined with TCP as TCP/IP.

IP Address - Internet Protocol Address. The address of an internet or local network site in numerical form (e.g.

IP Profile - A BT Wholesale configuration setting for ADSL Max, closely related to the bRAS profile. It is set automatically according to the user's lowest recent connection speed, and defines the maximum download speed which can be achieved on that connection. See IP / bRAS Profile. (

IP Stream - Type of adsl where the ISP uses BT Wholesale's backhaul and equipment at the exchange. - See IPStream  ( for more info on how it works.

IRC - Internet Relay Chat. A real-time medium for exchanging text messages over a network, mainly used in group discussion forums called channels.

IRQ - Interrupt Request. A computer hardware system which allows programs and hardware devices to interrupt the CPU and get some attention.

ISA - Industry Standard Architecture. An interface design for plug-in cards in a computer, now mainly obsolete.

ISDN - Integrated Services Digital Network. A digital telephone connection system allowing simultaneous transmission of speech and data. Now largely superseded by DSL broadband.

ISP - Internet Service Provider. The provider of internet services to the end user.

IT - Information Technology. An umbrella term for anything to do with computers and related subjects.
Title: Glossary - J
Post by: kitz on March 28, 2009, 10:06:28 PM
JPEG - Joint Photographic Experts Group. File type for digital images.

JRE - Java Runtime Environment.

JVM - Java Virtual Machine.
Title: Glossary - K
Post by: kitz on March 28, 2009, 10:11:32 PM
kb - Kilobit (1024 bits)

kB - Kilobyte (1024 bytes)

kbps - Kilobits per second

kBps - KiloBytes per Second, may also be denoted as KB/Sec

kHz - Kilohertz, a measure of frequency. 1 kHz = 1000 cycles per second.
Title: Glossary - L
Post by: kitz on March 28, 2009, 10:25:12 PM
L2TP - Layer Two Tunnelling Protocol.  A protocol that enables Virtual Private Networks.  L2TP is used by BTw for IP Stream ISPs to hide the BTw part of the network, so that the first hop a user will see will be the ISPs home gateway.

LAN - Local Area Network.

LCD - Liquid Crystal Display.

LEN - Line Equipment Number (BT)

Line Rate - The speed at which you connect (synchronise) to the exchange.

Line Stats - Statistics obtained from your router which gives information about the condition of your line and adsl connection.
                    How to get your line stats (  How to interpret your line stats (  A brief explanation of your line stat figures (

LJU - Line Jack Unit. - See BT sockets and Line Jack Units ( for more info and help identifying your LJU.

Local Loop - The telephone cabling network between the exchange and the customer premises.

LLU - Local Loop Unbundling.  When another telecoms provider or ISP installs their own equipment in the BT exchange and makes alternative arrangements for back haul provision.  There are 2 types of LLU - FMPF (or MPF) ( and SMPF.

LLUMS - Local Loop Unbundling Management System. An Openreach system primarily used to monitor and report on the status of each cabinet  DSLAM. It is also used to monitor the FTTC service take-up and trigger the addition of further line cards to the DSLAM.

LOL - Laughing Out Loud.

LTS - L2TP Tunnel Switch.  Also known as the ISP home gateway.  More info here (

Title: Glossary - M
Post by: roseway on March 28, 2009, 11:10:45 PM
MAC - Migration Access Code. A number which you obtain from your present ISP in order to migrate to a different ISP, without having to cancel and re-order.

MAC address - Media Access Control Address. A unique serial number which is assigned to a network adaptor to enable correct routing of data packets in a network.

Mb - Megabit. 1024 kilobits (kb).

MB - Megabyte, 1024 kilobytes (kB).

Mbps - Megabits per second (also written as Mb/sec).

MBps - Megabytes per second (also written as MB/sec).

MBR - Master Boot Record. The first 512 bytes on a disk, which are reserved for booting the machine.

MDF - Main Distribution Frame.  The point at which the copper pair terminates at the telephone exchange.  - See Inside the telephone exchange (

MF - Medium Frequency.

MHz - Megahertz, a measure of frequency. 1 MHz = 1 million cycles per second.

MPEG - Motion Pictures Expert Group. A file type for moving pictures.

MS - Microsoft.

MSAN - Multi Service Access Node.  Next Generation DSLAM which can support multiple transport technologies. More info MSAN (

MTU - Maximum Transmission Unit. MTU and RWIN (
Title: Glossary - N
Post by: roseway on March 29, 2009, 10:35:07 AM
NAS - Network Attached Storage. A data storage device which is connected to a network.

NAT - Network Address Translation. The process of changing the IP address in data packet headers passing through a network routing device, so as to remap one address space into another. Commonly used in domestic and office routers to provide a separation between the internal (LAN) addresses and the external publicly visible internet address. See Network Address Translation. (

NIC - Network Interface Card / Controller. A piece of hardware which enables a computer to connect with a network, usually built into the motherboard of modern machines.

NNTP - Network News Transfer Protocol. The protocol which is used for transferring news articles in Usenet, and also for transferring news between servers.

NOC - Network Operations Centre.

NTE - Network Terminating Equipment. 

NTE5 - Network Terminating Equipment. The BT Master Socket (

NTFS - New Technology File System. The file system which is used in all recent versions of Windows.

NTP - Network Time Protocol. A protocol for synchronising computer clocks over networks. A world-wide network of NTP servers are synchronised to highly accurate time sources, and computers can connect to these servers to maintain the accuracy of their own clocks.

NTP - Network Terminating Point.

NTTP - Network Terminating and Test Point (BT)

NTU - Network Terminating Unit.

NVRAM - Non Volatile Random Access Memory. A generic term for memory which does not lose its data when the power is disconnected.
Title: Glossary - O to Z
Post by: roseway on March 29, 2009, 12:52:16 PM
Glossary and Explanation of some of the common terms in use on this site.

A (   B (   C (   D (   E (   F (   G (   H (   I (   J (   K (   L (   M (   N (   O (   P (   Q (   R (   S (   T (   U (   V (   W (   X (   Y (   Z (   0-9 ( 

Title: Glossary - O
Post by: kitz on March 29, 2009, 01:22:11 PM
OEM - Original Equipment Manufacturer.

OLO - Other Licensed Operator(s).

ONT - Optical Network Terminal.

OOo -, an open source suite of office software.

OP - Original Post.

OP - Original Poster.

Open Source - A term used to describe software which is supplied complete with the original programming source code.

OS - Operating System, the software which makes a computer work, and enables the user to install and run application programs.

OT - Off Topic.
Title: Glossary - P
Post by: roseway on March 29, 2009, 01:56:58 PM
P2P - Peer to Peer. A distributed computer network in which each participant acts as both a server and a client. Commonly used for file sharing purposes.

PAP - Password Authentication Protocol. A simple unencrypted protocol to validate remote users logging on to a server. CHAP ( is generally preferred because it is more secure.

PATA - Parallel ATA. A parallel interface for disk drives, commonly referred to as IDE.

PC - Personal Computer. Generally used to refer to the 'IBM compatible' type of computer with an Intel compatible processor.

PCP - Primary Cross-Connection Point (BT)

PCB - Printed circuit board.

PCI - Peripheral Component Interconnect. A widely used interface for plug-in boards in a computer.

PCIe - PCI Express. An enhanced version of the PCI interface for use with high performance graphics cards.

PCMCIA Personal Computer Memory Card International Association. An international standards organisation which maintains the standards for PC Cards and ExpressCards.

PCM Pulse-Code Modulation. A digital representation of an analogue signal, made by sampling the signal at frequent intervals.

PDF Portable Document Format. A file format for the exchange of documents, created by Adobe Systems.

PING - Network utility used to check the response of a remote server or computer.  How to use the PING command (

PM - Personal Message / Private Message.

PNG Portable Network Graphics. A file format for bitmapped graphics. Supports 24-bit colour but not animation, and primarily intended for transferring images over the internet.

PnP - Plug and Play. An operating system based facility for automatic installation of plug-in devices.

POI - Point Of Intervention. (BT)

PON - Passive Optical Network.

PoP - Point of Presence.  Location or point where a network can be accessed. - See also Co location Centre (

POP3 Post Office Protocol v3. A commonly used protocol for the retrieval of emails from a server.

POS - Provision Of Service (BT)

POST - Power On Self Test. An early part of a computer's boot process, in which some tests are run to check the hardware.

POTS - Plain Old Telephone System.

PPC - Power PC. A type of processor used by Apple up to 2006, when they changed to the use of Intel processors.

PPP Point-to-Point Protocol. A data link protocol which is used to establish connection between two network nodes. Commonly used in dial-up internet connections.

PPPoA, PPPoE - PPP over ATM, PPP over Ethernet. Encapsulated forms of PPP used by ISPs to connect users to a DSL service.

PPPoA - PPP over ATM - BTw use ATM as on the exchange backhaul which sets up VCs (virtual Circuits) / VPs (Virtual Paths) for the routing - eg you enter VC and VPI nos when setting up your connection.

PPPoEoA - PPP over Ethernet over ATM - In the UK the vast majority of ISPs use PPPoA because they use the ATM backhaul from the exchange.  You may see some mention of PPPoE in the UK but in reality they likely use 'emulated' PPPoE (PPPoEoA) - still using the ATM backhaul.

PSTN - Public Switched Telephone Network

PSU - Power Supply Unit.

PVR - Personal Video Recorder.
Title: Glossary - Q
Post by: kitz on March 29, 2009, 02:15:19 PM
QAM - Quadrature Amplitude Modulation. Modulation method used to transmit adsl data.

QoS - Quality of Service. Control mechanisms for allocating and prioritising different data flows in a network. QoS is included in some routers, for example, to enable multiple users to each have a defined share of the capacity of the connection.

Quad Play - Combination of Landline, Mobile Phone, Broadband and Television services.
Title: Glossary - R
Post by: kitz on March 29, 2009, 02:23:05 PM
RADIUS - Remote Authentication Dial In User Service.  Authentication method used by ISPs to authorise your username and login.

RAID - Redundant Array of Independent / Inexpensive Disks. A means of distributing data over multiple disks so as to provide more security, or speed, or both.

RAM - Random Access Memory.

RAS - Remote Access Server.  More info on BT's RAS (

RAT - Request Auto Testing (BT)

RBAT - Request Background Automatic Test (BT)

REN - Ringing Equivalent Number. Each device plugged into the telephone line has a REN value. Maximum recommended REN is 4.

RF - Radio Frequency

RFI - Radio Frequency Interference

ROADM - Reconfigurable Optical Add/Drop Multiplexer

ROM - Read Only Memory

RSI - Repetitive Strain Injury

RTC - Real Time Clock

RWIN - Receive Window - See MTU and RWIN (
Title: Glossary - S
Post by: kitz on March 29, 2009, 02:40:04 PM
SATA - Serial ATA. A serial interface for disk drives, now taking over from PATA (IDE) (

SCP - Secondary Cross-Connection Point (BT)

SDSL - Symmetric Digital Subscriber Line.  DSL technology with the same upload and download data rate.

SFP - Small Form-factor Pluggable.

SHDSL - Single pair High bit rate Digital Subscriber Line.

SLA - Service Level Agreement.

SMF - Simple Machines Forum.  The software that runs forums such as this.

SMPF - Shared Metallic Path Facilities. LLU where the ISP provides broadband only.

SMTP - Simple Mail Transfer Protocol.

SNMP - Simple Network Management Protocol

SNR - Signal to Noise Ratio - SNR Explanation (

SNRM - SNR Margin.

SNR Margin -  May also be known as Noise Margin. See SNR Margin Explanation (

SP   - Service Provider(s).

SRA - Seamless Rate Adaption.  Explanation of SRA (

SSB - Service Selection Barring.  Method used by BT to ensure that you can only log into the correct ISP - see adsl authentication (

Sync - Synchronisation with the exchange.

STM - Synchronous Transport Modules.

STM1 - 155.52Mbps

STM4 - 622 Mbps (4 * 155.52)

SVLAN - Service Virtual LAN.

Sync Speed - Rate at which you connect to the exchange.
Title: Glossary - T
Post by: kitz on March 29, 2009, 02:51:31 PM
T&Cs - Terms and Conditions

TAM - Test Access Matrix.  ADSL diagnostic equipment - see Inside the BT Telephone Exchange (

TCP - Transmission Control Protocol

TCP/IP - Transmission Control Protocol/Internet Protocol

TIA  - Thanks In Advance

TPON - Telecommunications over Passive Optical Networks

TPS - Telephone Preference Service.  Opt out register for unsolicited sales and marketing telephone calls.  See TPS (

TLA - Three Letter Acronym

TLD - Top Level Domain

Tracert / Traceroute - Network utility used to check the routing to a remote server or computer.  How to use the Tracert command (

TY - Thank You.

TYVM - Thank You Very Much.

Title: Glossary - U
Post by: roseway on March 29, 2009, 04:17:25 PM
UBC - Usage Based Charging. BT wholesale method of charging ISPs based on the amount of bandwidth used by their customers - More information CBC/UBC (

UDP - User Datagram Protocol. One of the core internet protocols. With UDP a computer can send data to other hosts without having first to set up special channels or paths. Used for DNS, streaming media, many online games, etc.

UI - User Interface. The means by which a user interacts with the computer.

UPS - Uninterruptible Power Supply.

URI - Uniform Resource Identifier. A standardised way of specifying the address of an internet resource.

URL - Uniform Resource Locator. The full address of an internet resource, including the means of addressing it (e.g.

URN Uniform Resource Name. A standardised way to specify the name of an internet device (as opposed to the URL which is its address).

USB - Universal Serial Bus. A hot-pluggable serial interface.

UTC - Coordinated Universal Time. For most purposes, equivalent to GMT.

UTP - Unshielded Twisted Pair.
Title: Glossary - V
Post by: roseway on March 29, 2009, 06:47:07 PM
VC - Virtual Circuit.  A link between 2 points on a network specifically to route between the locations over a circuit.

VC - Virtual Channel.  A communication channel between 2 points on an ATM network.

VC-Mux -  Virtual Circuit Multiplexing. 

VF - Voice Frequency

VFAT - Virtual FAT. An enhancement of the FAT ( file system to support long file names.

VHF - Very High Frequency.

VISP - Virtual ISP.  An ISP that resells or bundles products from other Internet Service Providers rather than their own dedicated products. 

VLAN - Virtual LAN

VLF - Very Low Frequency.

VM - Virtual Machine, a means of installing an operating system inside another OS.

VM - Virtual Memory.  Extends RAM by using a portion of the hard drive.

VoD - Video on Demand. TV/Video Services available over the Internet streamed or downloaded to your PC.  Examples are BBC iPlayer, ITV Catchup, 4OD, BT Vision.

VoIP - Voice over IP. A general term for systems which deliver voice communications over the internet or other networks.

VP - Virtual Path. For more info see BT Virtual Paths (

VPI - Virtual Path Identifier.  Used in ATM networks to define the Virtual Path.

VPN - Virtual Private Network. A network in which some of the connections are made over another larger network, such as the internet.
Title: Glossary - W
Post by: roseway on March 29, 2009, 07:01:17 PM
W3C - World Wide Web Consortium. The international standards organisation for the world-wide web.

WAN - Wide Area Network.

WAP - Wireless Access Point.

WBC - Wholesale Broadband Connect.

WMBC - Wholesale Managed Broadband Connect.

WEP - Wired Equivalent Privacy. An encryption standard for wireless networks, now considered to be insecure.

Wi-Fi - Wireless Fidelity. A standard for interoperability between wireless devices.

WLAN - Wireless Local Area Network.

WPA - Wi-Fi Protected Access. An encryption standard for wireless networks, more secure than WEP.

WRT  - With Regard To / With Respect To.

WTH - What The Heck / What the Hell.

WWW - World Wide Web.

WYSIWYG - What You See Is What You Get. A term for document editing programs in which the editing display has the same appearance as the final document.
Title: Glossary - X
Post by: roseway on March 29, 2009, 07:04:54 PM
xDSL - Generic term encompassing all forms of DSL
Title: Glossary - Y
Post by: roseway on March 29, 2009, 07:06:01 PM
Y2K - Year Two Thousand.
Title: Glossary - Z
Post by: roseway on March 29, 2009, 07:10:38 PM
ZIF - Zero Insertion Force. A type of socket for integrated circuits, in which the IC is dropped freely into the socket and locked in place afterwards. Used for processors and similar devices.

Title: Glossary 0-9
Post by: kitz on March 29, 2009, 08:22:36 PM
21CN - 21st Century Network - BT Wholesale's upgrade for faster broadband and move from a PSTN (Public Switched Telephone Network) to an IP (Internet Protocol) System.

2G - Second Generation Mobile Technology.

3G - Third Generation Mobile Technology.  Allows faster services and access to the Internet.

4G - Fourth Generation Mobile Technology. "Super Fast" Mobile broadband - See Ofcom article here (