Glossary of Terms

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A

A system that handles incoming call traffic, sending calls to the first available station within predefined groups. If all stations are busy then a recorded message is played and the call is put in queue until a station becomes available.
ADSL: Asymmetric Digital Subscriber Line (ADSL) is a form of DSL, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. It does this by utilizing frequencies that are not used by a voice telephone call. A splitter - or microfilter - allows a single telephone connection to be used for both ADSL service and voice calls at the same time. Because phone lines vary in quality and were not originally engineered with DSL in mind, it can generally only be used over short distances, typically less than 4km.
ADSL 2 (+): Is a second generation broadband service that uses new technology to offer faster connections for more users. ADSL 2 provides download speeds of up to 12Mbps, while ADSL 2+ can double this. Both new systems are compatible with current ADSL networks and equipment, so upgrading to ADSL 2 or ADSL 2+ shouldn’t be a problem for your home. If you live very close to a BT exchange, your ADSL 2+ download speed may be faster than that experienced by connections further away.
Analog: A transmission method using continuous electrical signals, varying in amplitude or frequency in response to changes of sound, light, position, etc. impressed on a transducer in the sending unit. Analogue data often comes from measurements, like a sine wave. The opposite of analog is DIGITAL.
Anti-Virus: Antivirus software (or anti-virus) is computer software used to identify and remove computer viruses, as well as many other types of harmful computer software, collectively referred to as malware. While the first antivirus software was designed exclusively to combat computer viruses (hence "antivirus"), modern antivirus software can protect computer systems against a wide range of malware, including worms, phishing attacks, rootkits, and Trojans.
Asynchronous: A transmission method in which information is transferred one discrete character at a time and is delineated by a start and stop indicator at the beginning and end of the character. This way, if there is line noise, the modem can find out right away where the next byte should start. The opposite of asynchronous is SYNCHRONOUS transmission.
ATM (Asynchronous transfer mode): Not the money machine! This is an international CCITT standard for high-speed [broadband] packet-switched networks that operates at digital transmission speeds above 1.544 Mbps. This communications protocol specifies how diverse kinds of traffic are transformed into standardized packets which can be managed uniformly within the network.
Attendant: An operator of a PBX console or telephone switchboard.
Auto Attendant: An electronic version of an Attendant, see above, which provides callers with a menu of options to enable them to route themselves, if a caller does not select an option this commonly routes the call to a backup operator, group of phones or in some cases a voicemail box.

B

Bandwidth: The relative range of frequencies that can be passed without distortion by a transmission medium. Greater bandwidths mean a higher information carrying capacity of the transmission circuit. Bandwidth, usually measured in Hertz, is assessed as the number of bits that can be transferred per second.
The difference between the upper and lower limits of a band. A range of radio, audio, or other frequencies. Since it is so limited, a modem must carefully change data into sounds that "fit" within this range. Similar to frequency spectrum. Bandwidth of a voice channel is 3000Hz-300Hz which equals 2700Hz. Telephone lines have a bandwidth from 300 hertz to 3400 hertz.
B channel: Message-bearing 64 Kbps digital channel specified in the ISDN standards. B channels are used for digital transmission of high speed data and video.
Balun: Balanced/unbalanced. A device which connects a balanced (two-wire) line, such as a phone line, to an unbalanced (coaxial) line, like cable. The two-wire line is called balanced because the currents in each wire are equal and in opposite directions.
Baud: A term referring to the speed at which modems communicate. Technically, it is the number of changes in an electronic signal per second. Since the number of changes used to be the same as the number of bits sent or received per second, bps and baud are often used interchangeably. However, there is a difference, which is very often confused. For example, many 1200bps modems were advertised as 1200 baud, even though they operate at 600 baud. They send out 2 bits 600 times a second, which means that it is 600 baud. However, since it is so often misunderstood, you can assume that when you see "baud" it means bits per second, unless it is stated otherwise. The term comes from the scientist J. M. E. Baudot.
Bit: The smallest unit of digital information utilized by electronic or optical information processing, storage, or transmission systems. Bit is short for binary digit. Binary technology is based on the representation of data with 0's and 1's, whose combinations form a protocol medium for all data transmission. See also 8-N-1 in # section.
BPS: Bits Per Second. The transmission speed of most modems is measured in baud or bps. Bps is literally the number of bits sent by the modem every second. for local calls).
Broadband: Broadband in telecommunications refers to a signaling method that includes or handles a relatively wide range of frequencies, which may be divided into channels or frequency bins. Broadband is always a relative term, understood according to its context. The wider the bandwidth, the greater the information-carrying capacity. In radio, for example, a very narrow-band signal will carry Morse code; a broader band will carry speech; a still broader band is required to carry music without losing the high audio frequencies required for realistic sound reproduction. A television antenna described as "normal" may be capable of receiving a certain range of channels; one described as "broadband" will receive more channels. In data communications an analogue modem will transmit a bandwidth of 56 kilobits per seconds (kbit/s) over a telephone line; over the same telephone line a bandwidth of several megabits per second can be handled by ADSL, which is described as broadband (relative to a modem over a telephone line, although much less than can be achieved over a fiber optic circuit).
Byte: The smallest unit of information that a computer system can locate within its data storage or memory. A byte consists of eight bits and represents an amount of information roughly equivalent to a single printed or typewritten character.

C

Call Forwarding: A feature permitting the user to program a phone to ring at an alternate location; call forwarding may be in effect at all times or just when a particular phone is busy or doesn't answer.
Call Hold: A feature allowing the user to put one caller on hold while other calls are made or answered.
Call Park: A feature allowing a call for a busy extension to be put into a hold-like state until someone at that extension or another extension becomes free to answer it. The call is brought out of "park" by dialing a special code.
Call Transfer: A feature allowing a call to be transferred to another phone
Call Waiting: A feature that provides audible or visual indicators to let a single-line-phone user know that she has another call waiting for her.
Caller ID: A telephone company service allowing the subscriber to view the phone number and/or name of the calling party on a display device before answering the phone. Caller ID usually requires some kind of hardware phone interface to provide the displayed information.
Camp-on: In PBX and hybrid environments, a method of putting an incoming or outgoing call intended for a busy extension or line into a hold-like state where it remains until a line becomes available.
Card: A flat piece of rigid material bearing electronic components and the printed circuitry that interconnects them. Cards typically have one point where connections to other cards or components are made.
CCITT (Consultative Committee on International Telegraph and Telephone: The principle international standards-writing body for digital telecom networks (ISDN).
Carrier Detect: The information as to whether or not the modem senses a carrier, like a fixed-line dialling tone or a data/fax services enabled on a GSM subscription.
Cellular: Refers to communications systems that divide a geographic region into sections, called cells. The purpose of this division is to make the most use out of a limited number of transmission frequencies.
Each connection, or conversation, requires its own dedicated frequency, and the total number of available frequencies is about 1,000. To support more than 1,000 simultaneous conversations, cellular systems allocate a set number of frequencies for each cell. Two cells can use the same frequency for different conversations so long as the cells are not adjacent to each other.
For digital communications, several competing cellular systems exist, including GSM and 3G
CLIP: Caller Line ID Presentation. A code that is sent over the phone lines in some areas when a person makes a phone call. This code includes the phone number of the person making the call. Some modems are able to understand this signal, and let you know who is calling you before you answer the phone.
CLIR: Caller Line ID Restriction. The ability to block someone who you're calling from seeing your number.
CO (Central Office): A facility of a telecommunications common carrier where calls are switched. In local area exchanges, central offices switch calls within and between the 10,000-line exchange groups that can be addressed uniquely by the area code and first three digits of a phone number.
Codec (Coder/Decoder): a device that transforms analog input into a digitally coded output and transforms digital signals into analog output. They are most commonly found in videoconferencing systems because of videoconferencing's intensive ISDN usage.
Communciations Program: A program that controls a modem, and has features that allow the user to do such things as upload, download, etc. It is similar to a terminal program but more sophisticated. An example is Trumpet WinSock for connecting to the Internet, and Windows HyperTerminal.
Compress: To make data take up less space. Archiving programs do this, which means that files will take less time to transfer with modems. Many modems now have the ability to automatically compress the information they send and receive.
Conference Call: A telephone call among three or more parties. The sound quality of conference calls is typically degraded by a loss of sound over the telephone lines unless bridged and amplified before re-transmission.
CTS: Clear To Send. This is when the modem lets the other computer know that it can send information to the other computer.
CTS/RTS: The method of flow control that uses the CTS and RTS signals. It is built into the hardware, not software.

D

DCE: Data Circuit Terminating Equipment. Sets up and maintains a data connection link over a communications medium. For example, a modem.
Data Compression: Techniques to reduce the amount of computer memory space or transmission resources required to handle a given quantity of data usually achieved through the application of mathematic algorithms to the data transformation process.
Data Transmission rate: The speed at which data travels. For example, data may be sent at 115,200bps. Same as transmission rate, transmission speed, data rate.
dB: Abbreviation for decibel. The decibel is the standard unit of measure for expressing the amount of signal power gained or lost in the course of a transmission.
D Channel: The signaling and data transmission channel (specified in ISDN standards) used to transmit network control signals for setting up phone calls.
Dedicated Exchange Line or DEL: An analogue communications circuit or channel provided for the exclusive use of a particular subscriber - also known as a private line.
DID (Direct Inward Dialing): When a call is received over the DID circuit it is preceded by a packet of information containing the number that was dialed. The on premises phone system decodes this information and routes the call to the extension that has been programmed to coincide with the number dialed. The benefit to the consumer is a pooled access group for incoming calls so that dedicated lines are not required to provide numerous individual telephones with direct access availability.
DDI (Direct Dialling Inward): See DID above
Digital: A system using discrete numbers to represent data. In computer systems, these are the numbers 0 and 1 (for binary).
Digital Switch: Equipment used to set up pathways between users for transmission of digital signals.
DSR: Data Set Ready. This indicates that the modem is on, and ready to accept input from the computer (either commands or data to be sent over the phone line).
DTMF (Dual Tone Multi Frequency Signaling): Most commonly associated with AT&T's Touch-Tone trade name.
DTR: Data Terminal Ready. The DTR signal is sent from the computer to the modem, to let the modem know that the computer is ready to communicate.
Duplex: Simultaneous transmission in both directions, sometimes referred to as full duplex to differentiate it from half duplex, which is alternating transmission in each direction. Transmission in only one direction is called simplex transmission.
0800 Service: A telecommunications service for businesses that allows calls to be made to a specific location at no charge to the calling party. Use of the "0800" service access code denotes that calls are to be billed to the receiving party.

E

EEPROM: Electrically Erasable Programmable Read-Only Memory.
Encoder/Decoder: A device used to transform signals from an originating terminal into groups of digital pulses representing letters, numerals, or specific symbols, and transform incoming digital pulses into the form required by the receiving terminal.
Error Correction: Error Correction. The ability of a modem to notice errors in transmission, and to resend incorrect data.
ETSI: European Telecommunications Standards Institute.
Ethernet: A popular local area data communications network, originally developed by Xerox Corp., to accept transmissions from computers and terminals. More recently being utilized for voice services using voice over IP technologies

F

Fax: A method of transmitting graphics or text documents over a telecommunications facility. The image is scanned at the transmitter and reconstructed at the receiver to be duplicated on paper.
Fiber optic: A technology that uses glass (or plastic) threads (fibers) to transmit data. A fiber optic cable consists of a bundle of glass threads, each of which is capable of transmitting messages modulated onto light waves. Fiber optics has several advantages over traditional metal communications lines:
Fiber optic cables have a much greater bandwidth than metal cables. This means that they can carry more data. Fiber optic cables are less susceptible than metal cables to interference. Fiber optic cables are much thinner and lighter than metal wires. Data can be transmitted digitally (the natural form for computer data) rather than analogically.
The main disadvantge of fiber optics is that the cables are expensive to install. In addition, they are more fragile than wire and are difficult to split. Fiber optics. Fiber optics: is a particularly popular technology for local-area networks. In addition, telephone companies are steadily replacing traditional telephone lines with fiber optic cables. In the future, almost all communications will employ
Firewall: Computer security that attempts to keep crackers out.
Flow control: A method of controlling when information is sent. One method is Xon/Xoff, where a BBS will send information until your computer sends an Xoff (CTRL-S). It will resume sending information when you send an Xon.
Full Duplex: A communications system or channel capable of simultaneous transmission in two directions. See Duplex.

G

Gateway: A network element interconnecting two otherwise incompatible networks, network nodes, subnetworks or devices. 0 kb/s.
Group III Fax: The standard controlling fax communication.
GPRS: General Packet Radio Service is a standard for wireless communications which runs at speeds up to 150 kilobits per second, compared with current GSM (Global System for Mobile Communications) systems' 9.6 kilobits.
GPRS, which supports a wide range of bandwidths, is an efficient use of limited bandwidth and is particularly suited for sending and receiving small bursts of data, such as e-mail and Web browsing, as well as large volumes of data.
GSM: Short for Global System for Mobile Communications, one of the leading digital cellular systems. GSM uses narrowband TDMA, which allows eight simultaneous calls on the same radio frequency.
GSM was first introduced in 1991. As of the end of 1997, GSM service was available in more than 100 countries and has become the de facto standard in Europe and Asia.
GSM South Africa was one of the first to implement Phase 2 of GSM.

H

Half Duplex: A communications channel allowing alternating transmission in two directions, but not in both directions simultaneously.
Handover: What occurs when a cell phone used in a car moves out of the range of one cell and needs to connect to the next available cell. The preceding cell then hands over the connection to the stronger cell.
Hybrid: A combination of two or more technologies or a multiline business telephone system combining the manual line selection of a key system and the automatic line selection of a PBX system. Most commen application in todays market is systems that provide connectivity via analogue digital and/or I.P.

I

Interconnect: A company or vendor selling customer premises equipment, generally PBXs and other types of office telephone systems. An interconnect company is typically an independent distributor of products from more than one manufacturer.
IP: The Internet Protocol (IP) is a protocol used for communicating data across a packet-switched internetwork using the Internet Protocol Suite, also referred to as TCP/IP.
ISDN (Integrated Services Digital Network): Switched network providing end - to -end digital connectivity for simultaneous transmission of voice and/or data over multiple multiplexed communications channels and employing transmission and out-of-band signaling protocols that conform to internationally defined standards. Common UK variants are ISDN2e and ISDN30e and can be supplied with a number of additional options such as DDI numbers and CLI information inbound and outbound.
ISDN2e: Comprises 1 data channel which carries signalling information between the telephone exchange and the customers equipment. Plus 2 x 64K bearer channels which carry calls or data. Effectively this can be though of as to 2 voice lines, but in a data environment they can be bundled with a modem to provide a single 128K connection.
ISDN30e: Comprises 2 data channels which carry signaling and synchronization information between the customers equipment and the telephone exchange. Plus 30 x 64K bearer channels which carry calls or data. Effectively this can be thought of as 30 voice lines.
ISO: The International Standards Organisation, the body responsible for setting world technical standards. It is based in Geneva, Switzerland.
ITU: International Telecommunications Union, based in Geneva, Switzerland.
IVR (Interactive Voice Response): A generic term for transaction systems allowing phone callers to use an ordinary tone-dialing telephone to interact with a computer through speech or dialed instructions. Each response by the caller triggers another recorded message until the transaction is completed.

J

Jack or LJU (Line Jack Unit): A socket, hole or opening mounted on a wall, switchboard or panel, into which a plug connector can be inserted to complete a connection.

K

Key Telephone System: A multiline telephone system offering a range of features; key systems are popular among smaller businesses as their main telephone system. They are also found in large businesses as a form of extension to their big primary phone system. Key systems are characterized by manual selection of outgoing lines, their small size, and relatively low price.

L

LAN (Local Area Network): A transmission network encompassing a limited area, such as a single building or several buildings in close proximity; widely used to link personal computers so that they can share information and peripheral devices.
LLU: LLU (Local Loop Unbundling) describes the de-regulation of the former BT exchange network which allows 3rd party access to the last mile of copper wiring to a broadband users house. An ISP that provides LLU broadband will use ADSL or ADSL2 technology.
Local Loop: The “Local Loop”, describes the wires and equipment that connect your home to your local telephone exchange. Historically owned and maintained by BT, LLU means that other companies can now access the local exchanges.
Loop Start: A method of demanding dial tone from the central office by completing an electrical pathway between the outbound and return conductors of a telephone line. Loop start is employed by single-line telephone instruments, for example.

M

Microsoft: The world's largest developer and publisher of software based in Redmond, Seattle, USA. Headed by William (Bill) Gates, the richest (non-royal) person on this planet.
Modem (Modulator-Demodulator ): An electronic device that allows computers to communicate over standard telephone lines. It transforms digital signal into analog signal and transmits to another modem which then reconstructs the digital signal from the analog signal.
Modem: A MOdulator DEModulator computer peripheral which allows a computer to communicate over telephone lines. This is the heart of computer telecommunications. The main factor that differentiates modems is their speed, measured in bps. Analogue modems talk to one another by converting digital info from the computer into tones called PSK's. An ordinary analogue modem cannot be physically connected to a GSM phone because networks will not carry PSK tones.
Multiplexed Channel: A communications channel capable of serving several devices, or users, at once
Multiplexing: An electronic or optical process that combines a large number of lower-speed transmission lines into one high-speed line by splitting the total available bandwidth of the high-speed line into narrower bands (frequency division), or by allotting a common channel to several different transmitting devices, one at a time in sequence (time division). Multiplexing devices are widely employed in networks to improve efficiency by concentrating traffic.
Mux: An abbreviated form of the word multiplexer.

N

Network: Any system designed to provide one or more access paths for communications between users at different geographic locations that may include designs for voice, data, facsimile images and/or video images.
Network Architecture: A set of design principles defining the protocol, functions and logical components of a network and how they should perform.
Network Interface: The physical point in a telephone subscriber's home or place of business where the telephone devices and/or inside wiring of the subscriber are connected to the transmission lines of the local telephone service provider.

O

OEM (Original Equipment Manufacturer): The manufacturer of equipment that is resold by another vendor who usually substitute their name for that of the manufacturer on the product.
Off-Hook: A telephone set in use - the handset is removed from its cradle, thus sending an electrical signal to the central office that a circuit needs to be opened.
Off-Line: The condition where a terminal or device capable of active connection with the facilities of a computer or communications network is in the disconnected or idle state.
On-Hook: The normal state of the phone in which the handset rests in the cradle and the circuit to the central office conducts no electrical signal.
On-Line: The condition where a terminal or device capable of active connection with the facilities of a communications network or computer is in the active or connected state; a unit functioning under the continual control of a computer.
Open Standard: A computer or communications standard whose technical specifications are readily available to equipment manufacturers and other parties that want to incorporate the standard into their products or systems.
Open System: A computer or communications system whose technical specifications are readily available to distributors, users and other third parties that want to add value to the system by developing their own customized versions for use or resale. Open systems are widely cloned.
Operating System: A special program in the communications CPU or computer that controls the integration of operating devices and enables the running of specific applications software - which is software developed to perform specific jobs.

P

Packet: a group of binary digits switched as a whole - for instance, a file transfer over a packet switched network would require many steps. These steps are: 1) the data file would be broken down into smaller "packets" of information 2) each packet of information is assigned a code that enables it to be sent to the correct location and, once at that location, for the network to reassemble the packets of information into their original form.
Packet Switched Network: A digital data transmission network that uses packet switching technology.
Packet Switching: Refers to protocols in which messages are divided into packets before they are sent. Each packet is then transmitted individually and can even follow different routes to its destination. Once all the packets forming a message arrive at the destination, they are recompiled into the original message.
Most modern Wide Area Network (WAN) protocols, including TCP/IP, X.25, and Frame Relay, are based on packet-switching technologies. In contrast, normal telephone service is based on a circuit-switching technology, in which a dedicated line is allocated for transmission between two parties. Circuit-switching is ideal when data must be transmitted quickly and must arrive in the same order in which it's sent. This is the case with most real-time data, such as live audio and video. Packet switching is more efficient and robust for data that can withstand some delays in transmission, such as e-mail messages and Web pages.
Paging: A service designed to deliver numeric or alphanumeric messaging to a person whose location is uncertain - paging services make use of radio communications.
PBX (Private Branch Exchange): A device, installed on the customer's premises, that enables switching of multiple incoming and outgoing lines between multiple internal phones. In addition, the typical PBX provides for the selection of outside lines per user defined criteria.
PBX (2): Short for private branch exchange, a private telephone network used within an enterprise. Users of the PBX share a certain number of outside lines for making telephone calls external to the PBX.
Most medium-sized and larger companies use a PBX because it's much less expensive than connecting an external telephone line to every telephone in the organization. In addition, it's easier to call someone within a PBX because the number you need to dial is typically just 3 or 4 digits.
A new variation on the PBX theme is the centrex or featureline, which is a PBX with all switching occurring at a local telephone exchange instead of at the company's premises.
Port: An interface location on a computer or communications system that provides a point of access for peripheral equipment, such as printers, voice mail, C.O. Lines, etc.
POTS Lines (Plain Old Telephone Service Lines): Basic analogue telephone lines whose primary purpose is the transmission of human speech. A POTS phone being a standard analogue telephone similar to that used in a domestic type environment
Private Line: A telephone line that is linked directly to a user and is used exclusively by that user.
Private Network: A network that is designed for use exclusively by a person or organization and usually does not have points of access from users external to the company operations it is to perform.
Proprietary System: See closed system.
Protocol: A format or set of rules and conventions that control the format and relative timing of message transmission between two points on a computer network.
PSTN: Public Switched Telephone Network. This is the regular phone lines that just about everybody uses.
Public Switched Network: A switching system that provides switching and transmission facilities to many customers.
Pulse Dialing: A method that some phones use to dial numbers. It involves a series of "clicks." Most modems support this type of dialing, which is the only type available in some remote areas. The other method of dialing is tone dialing.

Q

Queue: A "holding room" for data or voice communications that are waiting to be processed by either the system or human intervention.

R

Real Time: A transmission or data processing operational mode in which the data is entered in an interactive (two-way communicating) session; an application where response to input is fast enough to affect later data input.
Redundancy: Having back-up systems available to provide continuous service in the case of a failure in the main system
Remote Access: Sending and receiving data to and from a computer through communications links such as phone lines.
Remote Call Forwarding: Similar to call forwarding. Calls from a local telephone number can be forwarded to long distance number (in another city for example) without the caller be charged for long distance fees.
Reset: A modem can be reset. This will change any options (such as parity and speed) to the values that they have when the modem is first used. This can be useful if you change some values for the modem and aren't sure what they do, and then you find that the modem won't work. Resetting the modem will fix everything for you.
Router: A router is a networking device whose software and hardware are usually tailored to the tasks of routing and forwarding information. For example, on the Internet, information is directed to various paths by routers.

S

SIM: Subscriber Identity Module. This is a Smart Card installed in every GSM handset. Within the GSM application the three primary roles of the SIM are access control to the network (authentication & ciphering), service personalisation (SMS, advice of charge, etc.), network branding and advertising (graphics printed on SIM card). The new generation of Phase 2+ SIMs will enable services such as virtual cash, mobile banking, ticket reservations etc.
SIP: A SIP (Session Initiation Protocol) connection is a service offered by many ITSP (Internet Telephony Service Providers) that connects a company's PBX to the existing telephone system infrastructure(PSTN) via Internet using the SIP VoIP standard.
Speed Dial: A feature on PBX phones allowing users to dial programmed numbers by simply pressing one button (or entering a two or three digit code).
Station: Simply another word for telephone. For example, the telephone station may be one of many extensions on a PBX system.
Station Hunting: A feature allowing an incoming call to a busy phone to be routed to the next idle phone in a pre-determined group of phones.
Switched Line: A circuit which is routed through a circuit switched network.
Switching: Connecting the caller to the called party.
Synchronous Transmission: Transmissions of data at a fixed rate, eliminating the need for start and stop bits, because the receiver and transmitter work at the same rate.

T

TCP/IP (Transmission Control Protocol/Internet Program): Protocols linking dissimilar computers across networks. TCP/IP was developed by the Department of Defense
TDM: Short for Time Division Multiplexing, a type of multiplexing that combines data streams by assigning each stream a different time slot in a set. TDM repeatedly transmits a fixed sequence of time slots over a single transmission channel. Within T-Carrier systems, such as T-1 and T-3, TDM combines Pulse Code Modulated (PCM) streams created for each conversation or data stream.
TDMA: Sort for Time Division Multiple Access, a technology for delivering digital wireless service using time-division multiplexing (TDM). TDMA works by dividing a radio frequency into time slots and then allocating slots to multiple calls. In this way, a single frequency can support multiple, simultaneous data channels. TDMA is used by the GSM digital cellular system.
Telecommunications: Process of converting sounds and data into electrical impulses that can be transmitted (See Telephony).
Telecommuting: Using a communications link to perform work, rather than actually commuting to an office to do work.
Teleconference: A conference which links people by audio and/or video through telecommunications.
Telemarketing: Using the telephone as a primary means of initiating and making sales of products or services.
Telephony: The process of converting sounds into electrical impulses for transmission over a connecting medium such as wires, fiber optics or microwave.
Terminal: The point of connection between a telephone line and an operative device. Also, sometimes terminal refers to the operative device, such as a computer terminal.
Tie Line: A telephone line which is dedicated to connecting two points and which requires a minimum human intervention to achieve communication.
Token Ring: A method of controlling which of several work stations in a Local Area Network is transmitting at a particular time.
Toll Restriction / Call Barring: A method of controlling which employees, if any, have access to telephone lines for which a toll may be charged to the employer.
Tone Dialing: This is a method that a phone or modem can use to dial a phone number. It uses one audible tone per digit to be dialed.
Transmit Level: The "loudness" level of the sound leaving a modem to go over the phone lines. It is measured indBm's. It should be different at different frequencies, since certain frequencies have more loss over the phone line than others.
Trunk: The line of communication between switching systems.
Turnkey: A ready-to-go telephone system installed by the vendor, including both hardware and software.
Twin-Axial Cable: Two commonly insulated conductors, covered by a metallic shield and enclosed in a cable sheath.
Twisted Pair: Two copper wires twisted around each other. The twists vary in length and reduce induction.

U

UART: Universal Asynchronous Receiver/Transmitter. This is a device in a computer or modem that will change serial data (the way data comes in over the phone line) to parallel, and vice versa. (See more details below in # section)
UMTS: Universal Mobile Telecommunication System - UMTS is a third generation mobile communication system currently being developed in Europe. UMTS related activities are lead by research conducted within the RACE II program and standardisation activities within the Europian Telecommunication Standards Institute (ETSI).

V

Videoconferencing: Video teleconferencing (See teleconferencing).
Voice Digitization: Coverting analog signals (voice) into binary bits for storage and transmission.
Voice Mail: Voicemail (or voice mail, voice-mail, vmail or VMS, sometimes called messagebank) is a centralized system of managing telephone messages for a large group of people. The term is also used more broadly, to denote any system of conveying voice message, including the answering machine.
VPN (Virtual Private Network): A private network that is configured within a public network e.g. a carrier's own network or via the internet utilising tunneling protocols such as IPSEC or LLTP. VPNs are widely used by enterprises to create wide area networks (WANs) that span large geographic areas, to provide site-to-site connections to branch offices and to allow mobile users to connect to their company LANs, taking advantage of the economies of scale and management facilities of large networks.

W

WWW: World Wide Web. A hypertext system set up on the Internet.
WAN (Wide Area Network): A network that extends LANs to other LANs, typically over a wide geographical area using communications lines provided by a common-carrier.
WAP: The Wireless Application Protocol is a secure specification that allows users to access information instantly via handheld wireless devices such as mobile phones, pagers, two-way radios, smartphones and communicators.

0 - 9

10BASE-T: An ethernet connection that uses UTP (unshielded twisted-pair) wiring to transmit data at 10Mb/s
100BASE-T: As above but running at 100Mb/s
1000BASE-T (Gigabit): Recent improvements in switching and cable technology have enabled the use of copper UTP (CAT5e and CAT6 standard) to transmit data reliably at upto 1000Mb/s