Access Network
The network which gives access to a telecommunication service. The access network is, for instance, the copper wire (twisted pair) between the house service connection and the telephone exchange of the network operator (local loop). Other examples are the wireless connection between a GSM handset and its GSM network or the coax cable of the cable television operator.
Access Server
A network element which provides access services. For instance an Internet access server provides access services by means of modems. It is also the access server’s task to concentrate data traffic, this explains the term access concentrator for the same definition. Another commonly used name is network access server. Whenever a remote location is used for access (in case of in-call services) the term remote access server is often used.
ADSL
Asymmetric Digital Subscriber Line. ADSL is a transmission technique for transporting a broadband signal with, an ISDN or telephone signal, by copper wire (twisted pair). The transmission speed is 6 to 8 Mbits/s downstream and about 1 Mbit/s upstream. In future it will be applied for services which take a wide bandwidth of the network into the direction of the subscriber, for example fast Internet access or VOD for the residential subscriber.
Applet
A small software program written in Java. Activating makes the applet to be downloaded on the network ( for instance Internet) and executed on a local computer.
ATF-3
(Also ATF-1 and ATF-2) PTT designation for an analogue mobile telephony network. ATF-3 is based on NMT technology. In time this network will be replaced by GSM/DCS1800.
ATM
Asynchronous Transfer Mode. A switching technology for building fast (wide band) networks. ATM can be used for transport of voice, computer data and video. In the early days ATM networks were known as Wide band ISDN. Nowadays we see ATM also as a switching technology in networks liken LAN’s and Internet. ATM is suitable for switching voice, data and video. There are ATM standards varying from 2 Mbits/s to 2.5 Gbits/s.
Bandwidth
Bandwidth means capacity of a transport medium. Larger bandwidth means the ability of transporting more information per second. Originally bandwidth is an analogue term. Bandwidth should be expressed in Hertz. Often bandwidth is expressed in bits per second.
Bandwidth on demand
On demand the user obtains capacity. Bandwidth on demand can be used for ‘usage based tariffing’, i.e. the user will only pay for used capacity. Some services, like leased lines, do not offer comparable flexibility. In that case the subscriber pays a fixed amount, independently of really using network capacity.
Billing
The process of arranging and processing the costs of the use of telecommunications services in order to present a bill to the subscriber.
B-ISDN
Broadband Integrated Services Digital Network. A (future) high speed network, based on ATM.
Bit Binary Digit
The smallest amount of information, recognisable for a computer. A bit is either ‘1’ or ‘0’. A standard for transmission speed (or capacity of a transmission medium) is bits per second. Therefore if the transmission speed is 64 kbit/s, 64000 bits per second are being transmitted.
B-Channel
An ISDN communication channel with 64 kbit/s capacity. The B-Channel is primarily used for sending voice or data. Between two sides, the B-Channels are switched by the ISDN using signalling information from the D-Channel.
Bps / bps (Bps)
Bytes-per-seconds or (bps) bits-per-second. 1 Byte contains 8 bits, so Bps is eight times as fast as bps. Note that this convention is often violated where Bps refers to bits-per-second instead of Bytes-per-second. To avoid confusion often written as bits/s or bytes/s.
Broadband
Broadband refers to a large capacity channel. During the 70’s ISDN (64 kbits/s) was considered broadband technology. Nowadays broadband means 2 Mbit/s or more. Broadband can be split into ‘broadband in the backbone’ and ‘broadband to the user’. Broadband in the backbone means a 2 Mbit/s or more network, but individually the user can not use this capacity. The network capacity has to be shared with other users. Exemplary are the telephony network and a 10 Mbits/s Ethernet LAN.
Broadband to the user means control for the user of a 2 Mbits/s or more dedicated bandwith. At this moment broadband applications are available ( for example Video on Demand, fast Internet access, high quality video conferencing).
Broadcast
Broadcast means sending identical information to all connections. Television distribution for example.
Browser
Software program for World Wide Web access. Commonly known browsers are Navigator (Netscape) and Explorer (Microsoft).
CableDECT
A technology based upon DECT. However the DECT protocol is not used for mobile communication. The used line is Coax of the CATV operator. DECT takes care of sustaining individual channels within a coax based shared medium. CableDECT can be the base for interactive cable services like telephony and Internet.
Cable-modem
A cable-modem can be used to provide interactive services over a CATV network. (like telephony and/or access of Internet)
CATV
Distribution of TV-signals on coax-cable.
CATV-operator
Organisation which manages and controls a distribution network for television signals. For instance Casema, Deutsche Telekom
CCITT
CCITT stands for Consultative Committee on International Telegraphy and Telephony. Formerly the ITU-T.
CDMA
Code Division Multiple Access. A technique for multi users share of the radio transmission spectrum. This technique is needed to give every user its own communication channel and also to use the available frequencies most efficiently. CDMA uses individual codes to make difference between traffic of different users. The most important alternatively used technique is TDMA.
CityRing
Most common meaning; a glass fiber infrastructure in an urban area, meant for high quality telecom services.
Compression
Process that codes an information stream into a smaller amount of bits to use capacity more efficiently. Can be divided up in ‘lossy’ compression (meaning reduction of orginal information) and ‘loss-less compression’ (meaning all original infomation can be restored).
Connectionless network
A network processes information packet-wise. Every packet has its own address and based upon that it will be send to the right location. The route of the packet is not defined beforehand.
CPE
Customer Premises Equipment. Equipment which is only meant for customers. The equipment is installed at the homes of customers or on industrial areas.
CT2
Cordless Telecommunications 2. A digital standard for wireless telephony. The system is in can be compared with DECT, however DECT offers more possibilities.
CTM
Cordless Terminal Mobility. Telecommunications service which offers mobility based on wireless entry to the public telephony network. CTM is possible with DECT extensions on a normal telephone exchange added with extra intelligence in the telephony-network. CTM can de positioned as a cheap alternative for GSM.
D-AMPS
Digital Advanced Mobile Phone System. D-AMPS is a standard for digital mobile networks. D-AMPS is an alternative for GSM. D-AMPS is commonly used in Northern America.
Dark Fiber
Telecommunications Service which gives a customer unlimited access to the fiber of the operator. The customer has to pay a fixed price.
Data
Generally, the term data is simplification of the term computer data, for example computer files which are send through the network.
DCS1800
DCS1800 is quite similar to GSM. The difference between DCS1800 and GSM is that DCS1800 uses another frequency (GSM on 900MHz, DCS1800 on 1800MHz). Because of the high frequency DCS1800 can handle a higher intensity of users. The handsets can also operate on a lower power level. However more base stations (antennas) are needed for the DCS1800 system.
DECT
Digital Enhanced Cordless Telecommunications. DECT is a standardised wireless system. This system is used in company areas (wireless PBX). In the nearby future DECT will also be used in domestic environments and possibly become the wireless gateway to the fixed telephony network. DECT is a high quality standard (better than GSM) and offers mobility too. It can also handle high density traffic i.e. many users in a certain area.
D-Channel
A communication channel used in ISDN with a capacity of 16 or 64 Kb/s. The D-Channel is mostly used for signalling-information between user and network.
Download
To transport computer data from one computer (for example: a network computer) to another (for example your own PC). Opposite of ‘upload’
DTMF: Dual Tone Multiple Frequency
A system that translates the keys on a telephone into audio signals readable for telephone exchange. Many telephone exchanges and IVR-systems can be controlled by DTMF tones.
DVB: Digital Video Broadcasting
A digital method to transport Video signals through a CATV network.
E-commerce
E-commerce is the general term for electronic payment and electronic banking. It concerns for instance the payment with a chip card (or charging the card), payments by Internet (for example by sending a credit card number), electronic payment between companies in a business section, etc.
Electronic highway
(Inter)national infrastructure suitable transporting information very quickly (for example fiber, fast switches, etc.). The electronic highway is very important from an economical point of view, since a good infrastructure to transport information is essential for organisations to manage their businesses. Electronic highway is often used as a synonym for Internet, which is not correct!
Ethernet
Ethernet is a certain technique for a LAN (Local Area Network) environment with a 10 Mbits/s rate. The standard is set by the IEEE. Since Ethernet is the cheapest available technique it is the most frequently used technique.
ETSI
ETSI is the abbreviation of European Telecommunications Standards Institute. This institute records standards for telecom equipment.
FDMA
FDMA is the abbreviation of Frequency Division Multiple Access. This technique is used to share the spectrum of radio transmission in a way it can be used by multiple users. Each user will have its own communication channel. FDMA uses different frequencies to distinguish users. Alternative techniques are: CDMA and TDMA. For GSM, combined use of TDMA and FDMA takes place.
Firewall
A firewall is a filter for certain data transport. A firewall can be used for separating Internet (available to the public) and Intranet (limited access, only for employees for example).
Frame Relay
Frame Relay is a package switched technique used in a computer data environment. Frame Relay is standardised by ETSI, ITU-T and the Frame Relay Forum. To a certain level it can be compared with X.25. The difference is that the overhead is taken out. In this way Frame Relay can work faster. Frame Relay can be used to support many forms of data transport, because packages of data are wrapped up in the same way. Frame Relay is a connection oriented technique. Frame Relay is frequently used to connect two LANs at different locations.
FTP
FTP is the abbreviation of File Transfer Protocol. A tool to transport files from one computer to another (by Internet for example).
Gateway
A Gateway is used to give access from one network to the other. The term gateway is used in both the data-communication and the telecommunication branch. Of course the apparatus differ among these branches. For data-communication a sort of router is used while for telecommunication some kind of telephone exchange is used.
Gbps
Gbps stands for Gigabits per second (Gbits/s). This means that the transmission speed is one milliard (USA: billion) bits per second.
GEO
GEO is the abbreviation of Geostationairy Earth Orbit. GEO stands for a certain altitude of a satellite. Besides GEO satellites there are MEO and LEO satellites which are closer to Earth. A satellite is called geostationair if it does not move relative to the surface of Earth. The altitude of a GEO satellite is 36000 kilometre above the equator and therefore circles around Earth in 24 hours.
GSM
GSM stands for Global System for Mobile communication. GSM is a digital, cellular system for mobile communication services. GSM is originally an European standard, but is now also used in other parts of the world. GSM can use three frequencies: 900 MHz, 1800 MHz and 1900 MHz. The 1800 frequency is called DCS1800 and the 1900 frequency is called PCS1900.
HFC
HFC means Hybrid Fiber Coax. HFC is used for a network infrastructure and consists of fiber and coax. For example fiber is used to a certain point in the street. From that point on coax is used into houses. A modern cable TV network is designed with HFC.
HTML
HMTL is the abbreviation of Hyper Text Markup Language. Programming language to design information pages on WWW and to make hyperlinks (added entry that can be activated) possible.
HTTP
HTTP stands for Hyper Text Transfer Protocol. HTTP is a protocol for viewing www-pages.
IBCN
IBCN stands for Integrated Broadband Communication Technology. IBCN is synonym to B-ISDN.
ICT
ICT stands for Information and Communication Technology. It is a general term for the telecommunication, computer-technology, Information Technology (IT) and possibly media (TV, video).
Internet
There are many ways of defining Internet. Internet could be defined as a new medium for communication, which is additional to TV, radio, newspapers and telephony. Looking at Internet from a telecom’s perspective, it is a huge collection of many networks linked together. From a user’s point of view, Internet provides, access to databases, communication and the possibility to give information to others. Often Internet is incorrectly called "the electronic highway" and is used as synonym for WWW.
Internet Connection oriented network
A network in which the connection is made first (circuit switched), then the information is transported. Examples are the telephony network (PSTN), ISDN and ATM.
Intranet
The use of Internet technology of in a network of a company is called Intranet. Intranet is a Closed Users Group, which is able to communicate and use shared software. Intranet is separated from Internet by means of a firewall.
IP
IP is the abbreviation of Internet protocol. IP is a protocol which has an important functionality in Internet. IP is a protocol which can be used in several kind of networks (ATM-networks, ISDN, LAN etc.) IP is needed for several services, like E-mail and WWW. IP is often used with TCP.
IP-switching
The term IP switching is used for all techniques of combining, routing (specifically IP) and switching (specifically ATM). Examples of these techniques are MPLS, MPOA and the original "IP switching" developed by Ipsilon. IP data, telecommunicationdata
IPv6
IPv6 also called "IP next generation", is the latest version of IP. It can handle telephony and video better than the last version. IPv6 is also the solution of the deficit of IP-addresses (user-addresses) of Internet.
ISDN
ISDN is the abbreviation of Integrated Services Digital Network. ISDN is a standard for digital communication. ISDN can easily support several services like telephony, communication of data and video. ISDN has the possibility to use of one or several channels of 64 kbit/s. De most important standard ISDN interfaces are BRA en PRA. BRA has two B-channels. For example one to telephone and one to use Internet. PRA has 30 B-channels. For example to connect a PBX to the public network of telephony.
ISP
ISP is the abbreviation of Internet Services Provider. An ISP is a company which provide access to Internet. Some Internet Services Providers deliver extra services by making web pages, for companies, with interesting information. Examples of ISP in the Netherlands are Planet Internet, World Online, and XS4all.
ITU-T
International Telecommunications Union Telecommunications Standards Sector. ITU-T is an world wide organisation which creates and records standards for telecommunication in general.
kbit/s kbps
kbit/s or kbps means kilobits per second. This is the dimension for transmission speed in one thousand bits per second.
LAN
LAN is the abbreviation of Local Area Network. An example of LAN is a network of a company, which connect several printers, servers etc. The most common medium for communication by LAN is Ethernet.
Leased Line
Leased Line is a telecommunication service. The subscriber has the disposal of a permanent connection and defined capacity for a fixed tariff. For example, a leased line can be used between two locations to connect their PBX or LAN. If telephone lines are used intensively (for example ticket machine), it can be advisable to use a leased line instead of a regular telephone connection.
LEO
LEO is the abbreviation of Low Earth Orbit, also called Intermediate Circular Orbit (ICO). LEO satellites circle at hights of 700-1000 kilometres around the world in two hours. A well known LEO satellite system is IRIDIUM. GEO satellites and MEO satellites circle in higher orbits.
Local Loop
Local loops are the cables in the public network of telephony from local exchange to the user.
Long distance carrier
Provider of long distance telephony in the USA. The largest providers in the USA are AT&T, Sprint and MCI. A new law in the USA says that RBOC’s and long distance carriers are allowed to compete with each other.
Mbit/s Mbps
Mbit/s or Mbps means mega bits per second. This is the dimension for transmission speed in one million bits per second.
MEO
MEO is the abbreviation of Medium Earth Orbit, also called Intermediate Circular Orbit (ICO). MEO satellites circle at hights of 10.000 kilometres around the world. They are not geostationary, which means they have relative speed in regard to the earth. GEO satellites circle in higher orbit than MEO satellites.
Modem
Modem is the abbreviation of Modulation/demodulation. A modem is necessary to transport digital data over analog lines (for example data from Internet over telephone-lines).
Mobilofonie
Mobilofonie was one of the first possible ways of mobile communication. Mobilofonie is a closed group of users, who are able to communicated with each-other directly or with the help of a exchange. The communication is mostly half-duplex, which means that only one person is able to talk at the same time. Mobilofonie is for example used by police and the fire-brigade and is than called PMR (Private Mobile Radio).
MPEG
MPEG is the abbreviation of Motion Picture Experts Group. MPEG is a code for moving pictures. This code uses less information (bits). A high quality video-signal can be encode in for example a bitstream of 1Mbit/s.
Multimedia
A way to present information to the user; it contains a combination of speech, video, pictures, text, computerdata and sound. There are a lot definitions of "multimedia". The term is used in many different ways, for example multimedia PC (PC with sound , graphic functions and CD-ROM), multimedia presentations (presentations with the use of films and pictures), multimedia application (telecommunication-service where pictures, sounds and computerdata is exchanged between the users). See also videoconferencing.
Narrowcast
Situation where the same information is sent to a selective group of destinations.
NC
Network computer. Computer that is optimised for the use of Internet. For example, it doesn’t contain a harddisk and is therefore less expensive.
N-ISDN
Narrowband Integrated Services Digital Network. This is the term used for the ordinary ISDN, that is based on the use 64 kbit/s channel.
N-VOD Near Video on Demand. A technology which allows you to select and watch a movie from a distance using a communication network. VOD allows you to select the exact movie you want on the exact time you want. With N-VOD you depend on a programme (for example the film starts once every hour).
OSI
Open System Interconnection. The OSI-model is a reference model for the design en realisation of computer- and telecommunicationnetworks. It is based on the principle of layered protocols (protocolstack).
Pay Per View
Pay TV, where a consumer pays to watch a specific movie at specific time, as scheduled by the Pay Per View organisation.
PC Personal Computer
The PC used to be a calculator, after that it became more and more a typewriter. In the future it will develop into a multifunctional apparatus for communication.
PCS1900
PCS1900 can be compared with GSM. The only difference is the use of an other frequency: GSM is based 900Mhz where PCS1900 is based on 1900Mhz (and DCS1800 is based on 1800Mhz). PCS1900 is used in the United States of America.
PDA
Personal Digital Assistant. A small computer with a build in cellular radio (GSM).
POTS
Plain Old Telephony System. The ordinary telephony system. Term used to refer to telephony services, mostly used in a context where terms as ISDN and more advanced technologies are used.
PPV
Pay Per View
PRA
Primary Rate Access. A standardised digital ISDN-interface. The speed is 2Mbit/s, the PRA is structured in 30B-channels and a D-channel for signalling. The PRA is mostly used for the connection of a PABX with a public telephony network.
PSTN
Public Switched Telephony Network. The public network for (analogue) telephony.
PTO
Public Telecom Operator. A company that exploits telecommunicationnetworks and telecommunicationservices. Examples: PTT-telecom and NWD
Router
A network element that takes care of the routing of informationpackages from the source to the right destination. Most of the routers route IP-traffic.
RSVP
Resource Reservation Protocol. A function within Internet (or an Intranet) which allows you to reserve bandwidth. This will increase the possibility to offer video-services and telephony over the internet.
SDH
Synchronous Digital Hierarchy. A high speed (155Mb/s) technology for digital transmission of telecommunication-traffic. SDH can be used as a carrier for ATM. SDH is in comparison with PDH more reliable.
Service Provider
An organisation which puts telecommunication services on the market. A service provider may use the infrstructure of a network operator. Debitel and Liberphone are for instance service providers for cellular radio services.
SMS
Short Message Service. Message service standardised for GSM-networks. By using SMS short messages can be send an received with a cellular phone.
STM
Synchronous Transfer Mode. A switching technique based on TDM. STM is often confused with SDH.
T1
American transmission standard for 1.5Mbit/s connections. Also known as DS1
T3
American transmission standard for 4.5Mbit/s connections. Also known as DS3
TCP/IP
TCP and IP are two protocols, used for the communication over Internet. E-mail and other services make use of these protocols.
TDMA
TDMA is the abbreviation of Time Division Multiple Access. This technique divides the spectrum of radio-transmission for multiple-use. Every users of the spectrum has its own communication-channel. TDMA makes use of several time-slots (also TDM), to separate the communication traffic of different users. TDMA is used in GSM. The most important alternative is CDMA.
Twisted pair/UTP
UTP is the abbreviation of Unshielded Twisted Pair. UTP is a copper transmission cable for communication. In contrast with "Shielded Twisted Pair (STP)", UTP doesn’t have a jacket of copper, which exclude distortion. UTP is used in many ways, for example in business- and other buildings. UTP is also used for local loop.
UMTS
Universal Mobile Telecommunications System.
UTP
see Twisted pair.
VDSL
VDSL is the abbreviation of Very high-speed Digital Subscriber Line. VSDL is a technique for the transportation of "wide-band signals" through a cable (twisted pair). The transmission-velocity could be 25 till 50 Mbit/s downstream and 1 Mbit/s upstream. VDSL could be the future successor of ADSL.
Videoconferencing
This is an application makes it possible to communicate with each-other with video and sound. Sometimes the user could also make use of data-signals during a conference. Videoconferencing is the example of a multimedia application in a telecommunication-network. There are many standards for video-conferencing. The most important standard is H.320.
VOD
VOD is the abbreviation of Video on Demand. This is a technology which make it possible to select a video and broadcast it on a communication-network. VOD has the possibility to start the video every moment the user wants. NVOD has the possibility to start the video on regular times.
W-CDMA
W-CDMA is the abbreviation of Wideband Code Division Multiplexed Access. This a wireless technology, based on CDMA. W-CDMA makes it possible to build transportation with high capacity. For example, W-CDMA can be used for mobile Internet and video-communication.
Web-TV
Web-TV is a concept for the use of television for Internet-services.
WWW
WWW is the abbreviation of World Wide Web. WWW is a popular communication-platform. HTTP makes it possible to broadcast and receive text, pictures (moving or not) and sound on the communication-platform. Often WWW is incorrectly as synonym for Internet.