Access Server

An Access Server or Network Access Server connects devices to a Local Area Network (LAN) or Wide Area Network (WAN). Internet Service Providers are able to provide customers with Internet connectivity using the Access Server. The server provides user authentication and permits the flow between the user host and hosts.


Asymmetric Digital Subscriber Line (ADSL) uses existing copper telephone lines to send and receive data at speeds that far exceed conventional dial-up modems. The technology is used to provide high-speed Internet access along the same line used for voice or telephony services. ADSL maximum data transfer rates differ for uploading and downloading data.

Auto Attendant

An automated system designed to guide a caller through the options of a voice menu. Typically set to answer and route incoming calls.



Bandwidth refers to the size of a data connection’s capacity. Bandwidth is usually measured in kilobits per second (Kbps), Megabits per second (Mbps) or Gigabits per second (Gbps). Circuit (access), a physical circuit is a wire or a part of a wire which provides a communications route between two or more points on a network. The circuit, sometimes described as a local loop connects a customer premise to a switch, router, multiplexer, or other device at the edge of a carrier or service provider network.


A term used to describe fast internet access. Wide bandwidth which can be either ADSL or SDSL. ADSL can suffer from vast bandwidth changes (see also Contention Ratio).



DDI allows users to rent individual phone numbers without the need to rent individual lines. A single phone line is allocated to a range of numbers saving the expense of having a separate phone line for each number.


Stands for ‘Digitally Enhanced Cordless Telecommunications’. A technology used to link cordless mobile handsets to a wired telephone system.



Ethernet describes the physical network that carries data traffic. The most commonly used technology for implementing Local Area Networks (LANs) Ethernet, is used to define how data is transmitted between computer devices. Computers, printers and devices are connected to each other through the hub/switch/bridge using cables in a star-like or a bus-like configuration. Ethernet initially supported a theoretical data rate of 10 megabits per second but today can extend to 10 gigabits per second (Gbps).

Ethernet Demarcation Device (EDD)

An Ethernet Demarcation Device enables Ethernet services to enterprises and business subscribers. Owned by service providers and located at the customer premises, it provides a clear demarcation point between customer and service provider networks. As well as delivering managed services to customers with Quality of Service (QoS) control for each service, these devices have all the necessary carrier-class management and Operations, Administrations and Management functions essential for service providers to monitor network health and performance up to the demarcation point.

Ethernet VPN

Ethernet VPN is a group of technologies used to provide Virtual Private Network services over the Internet between the Ethernet LANs. One of the Ethernet VPN technologies is based on Virtual Private LAN Services (VLPS) and Multiprotocol Label Switching (MPLS), which provides more benefits than other alternative Layer 2 or 3 VPN technologies.


Fibre Optics

Fibre Optics is a method for the transmission of data using optic Fibre cable and light. Light is transmitted over high purity, hair-thin fibres of glass. The bandwidth capacity of Fibre optic cable is much greater than that of conventional cable or copper wire.

Fibre To The Cabinet (FTTC)

This is a generic term for any broadband service that uses fibre optic cable, in place of traditional copper wiring, to connect a telephone exchange to the 'green cabinets' in the surrounding roads. This means that copper wires are only used in the last few hundred metres between a green cabinet and a customer's premises. Unlike copper, fibre does not suffer from signal loss over distance and so provides much faster download and upload bandwidth speeds.


A firewall is a protective security screen (hardware or software) that aims to protect network devices from hostile intrusion, viruses or malicious activity over the network. A corporate network’s traffic flows through the firewall and access to a corporate or private network is granted or denied.


Gigabit Ethernet

Gigabit Ethernet is a transmission technology based on the Ethernet protocol with speed tenfold over the fast Ethernet supporting a theoretical maximum data rate of 1000 Mbps or 1 Gbps. Ethernet operates at Layers 1 and 2 of the 7-layer Open Systems Interconnection (OSI) networking model, delivering its data packets to any device connected to the network cable.

Gigabits per Second (Gbps)

Gbps is a measure of the speed of data transfer in networking.


Hosted Telephony

Hosted Telephony is an Internet Protocol (IP) based phone system which is hosted in a service provider’s data centre removing the need for phone system hardware. Customer profiles are controlled via web-based browsers and can be edited by the end-user via an Internet connection.

Hunt Group

Multiple phones allocated to a single extension number which enable a call to be answered by any one person within a group. Calls will generally ‘hunt’ from one phone to another until answered.


Integrated Services Digital Network (ISDN)

Integrated Services Digital Network (ISDN) a network technology that provides digital transfer of simultaneous voice and data traffic and works over ordinary telephone lines. Local Area Network (LAN) A LAN is a data network connecting devices including computers, printers and servers in one location for fast and secure internal communication.

IP Address

Internet Protocol Address (or IP Address) is a unique address in number format which every computer device has. The IP address enables computer devices to communicate with each other over an IP network or the Internet. In order for data to be sent from one computer to another over the Internet, a data packet must be transferred across the network containing the IP addresses of both devices. The unique IP address allows data to reach the right destination.

IPv4 and IPv6

Internet Protocol Version 4(IPv4), is the most commonly used numbering system used to create IP addresses. IPv4 employs 32-bits of recombined digits and has a maximum of 4.3 billion possible addresses. IPv6 is a newer system for the creation of IP addresses. It uses 128 bits instead of 32 bits for its addresses, creating trillions of new IPv6 addresses, enough to support the demand for IP addresses for some expected time to come



Stands for ‘Local Area Network’ – Data network that connects computers, servers, printers etc together, generally within one physical location

Leased Lines

A leased line is a service contract between a provider and a customer, whereby the provider agrees to deliver a symmetric telecommunications line connecting two or more locations in exchange for a monthly rent (hence the term lease). It is sometimes known as a "Private Circuit" or "Data Line" in the UK. Unlike traditional lines it does not have a telephone number, each side of the line being permanently connected to the other. Leased lines can be used for telephone, data or Internet services.

Like For Like Transfer (LFLT)

A Like For Like Transfer is the order placed with Openreach by the new supplier for the transfer of the telephone lines. The process itself involves a member of Openreach administering the change from the incumbent supplier to the new supplier so that billing is then carried out by them. A LFLT typically takes twelve working days and involves no physical downtime



Megabit per second (Mbps) is a measure of the speed of data transfer in networking.

Multiprotocol Label Switching (MPLS)

Multiprotocol Label Switching (MPLS) is a networking technology which is used to route data packets over an IP network. MPLS ensures that all packets in a particular flow take the same route over a backbone. When used for a corporate VPN/WAN, the technology eliminates the need to buy and manage multiple firewalls as traffic is routed within a secure virtual private network.


Network to Network Interface (NNI)

Network to Network Interface (NNI) is both a physical and logical point of demarcation defining how two networks interconnect and exchange information. The NNI serves the technical boundary where protocol issues are resolved and as the point of division between the responsibilities of individual service providers.


Point of Presence (PoP)

A Point of Presence (PoP) is the point at which a telecoms carrier establishes a physical presence in a geographic area, and at which the local exchange carriers (LECs) terminate access services. The PoP can consist of the highspeed telecommunications equipment and technologies that enable users to connect to the Internet via their ISP. The PoP can include call aggregators, modem banks, routers, and high-speed Asynchronous Transfer Mode (ATM) switches.

Presentation Number

Enables the option of "masking" the main outbound number of a telephone line with a different number. This option is useful for call centres or companies that are located in obscure locations and don’t want end users to know their physical location or if they want to present a non-geographic number to the customers they are calling. For example, a company has a simple 0207 number but they want an 0845 number to be displayed to every end user that they call.

Private Branch Exchange (PABX or PBX)

Private Branch Exchange (PBX) is a switch station for telephone systems. Serving as the exchange point for the routing of incoming and outgoing calls, PBX consists of several branches of telephone systems and switches.


Quality of Service (QoS)

QoS is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow. QoS involves prioritization of network traffic. QoS can be targeted at a network interface, toward a given server or router's performance, or in terms of specific applications. A network monitoring system must typically be deployed as part of QoS, to insure that networks are performing at the desired level.


Remote Call Forwarding (RCF)

A method for forwarding calls made to a ceased line to a new number, without the caller being aware that the call has been forwarded. There is normally a set up cost and monthly charge for this service. In addition the owner of the line has to pay the cost of the forwarded part of the call, as well as the exchange line rental for the ceased line (this is because the number of the ceased line cannot be reallocated to another user whilst RCF is in effect.


A device (or, in some cases, software on a computer) that directs IP packets to the next point toward their destination.



Stands for 'Session Initiation Protocol'. It is essentially a communications protocol used to set up and clear down sessions with one or more users over the internet. Can be used in a multitude of scenarios, but most common is in the initiation and termination of Voice over IP calls.

SIP Trunks

Basically an internet phone line. Part of the broadband bandwidth is allocated solely for a VoIP call. Each VoIP call requires one SIP trunk but a good quality broadband service can accommodate multiple SIP trunks. SIP trunks are much cheaper to rent than traditional phone lines.

Site Assurance

Only available on ISDN30 lines. This service allows you to pre-pr0gramme a number that you would like your ISDN30 lines to divert to in the event of a line failure or other emergency. The divert can be activated within one hour by calling a specific phone number and quoting a password which you are given at the time of setting up the service. There is a monthly charge for this facility, whether or not you use it. Charges will also be incurred for the diverted part of the call when the diversion is activated.


Stands for 'Service Level Agreement' - part of a service contract where the level of service is formally defined. In practice, the term SLA is sometimes used to refer to the contracted delivery time (of the service) or performance.


Telephone Preference Service (TPS)

The Telephone Preference Service (TPS) is a central opt out register whereby individuals can register their wish not to receive unsolicited sales and marketing telephone calls. It is a legal requirement that companies do not make such calls to numbers registered on the TPS


Virtual Private LAN Service (VPLS)

VPLS is a class of VPN that supports the connection of multiple sites in a single bridged domain over a managed IP/Multi-protocol Label Switching (MPLS) network. The goal is to overcome the limitations of traditional protocols, any-to-any, full-mesh service across a Wide Area Network. All services in a VPLS appear to be on the same LAN, regardless of location. This removes complexity from enterprise networks, and lets carriers scale the networks.

Virtual Private Networking (VPN)

VPN provides secure connections between private networks linked through private networks or public networks such as the Internet. It allows remote computers to act as though they were on the same secure, local networkideal for linking multiple sites, home-based or remote workers. The main benefit of a VPN is the lower cost needed to support this technology compared to alternatives like traditional leased lines or remote access servers.


Virtualization refers to technologies designed to provide a layer of abstraction between computer hardware systems and the software running on them. With virtualization, an entire server (including processor and storage) runs as a software image, meaning multiple virtual machines can be run on one physical machine.

VOIP (see Hosted Telephony)

Stands for ‘Voice Over Internet Protocol’ - Voice translated into data packets and transmitted across an internet connection or network - just like any other file or email you might send. Upon reaching the other end data is transformed back into its original form and emerges like a regular phone call. (VOIP is critically dependent upon the speed of the packets across the internet and the correct assembly order once they arrive at their destination …for obvious reasons!)


Wide Area Network (WAN)

A WAN is a network covering a broad area and connecting multiple smaller networks across local, regional, or national boundaries. Multi-site organizations can use them to link LANs together (see LAN). 

Free Telecoms Review Check Broadband Speed