Glossary of Terms

Search for glossary terms (regular expression allowed)


Term Definition
Ethernet Demarcation Device

An Ethernet Demarcation Device enables Ethernet services to enterprises and business subscribers. Owned by service providers and located at the customer premise, 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.


DWDM (Dense Wavelength Division Multiplexing) is an optical multiplexing technology used to increase bandwidth over existing fibre networks. It works by combining and transmitting multiple signals simultaneously at different wavelengths on the same piece of fibre..

Direct Dial Inbound

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.


Desktop as a Service (DaaS) is a cloud service in which the back-end of a virtual desktop infrastructure is hosted by a cloud service provider. DaaS has a multi-tenancy architecture and the service is purchased on a subscription basis.

Data Centre hosting

Data Centre hosting describes the hosting of Data Centres or databases on third party servers. Data Centre hosting is often done through colocation solutions and therefore avoids expensive on premise server and hardware purchases.


IP convergence is the consolidation of Networks (e.g. Voice, data, video) into a single platform lowering the cost of Networks and communications.


Colocation is where an organisation houses its servers in a server room in a third party Data Centre, and uses a service provider for the provision of Network connections such as Internet leased lines to several servers which are housed together in a server room.

Cloud Computing

Cloud Computing refers to a Network of remote servers hosted on the Internet rather than a local server or computer which are used to process, manage and store data. Cloud Computing is broken down into three common service levels: SaaS, PaaS and IaaS. See definitions.


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.

Business Continuity

Task of identifying, developing, acquiring, documenting, and testing procedures and resources that will ensure continuity of a firm’s key operations in the event of an accident, disaster, emergency, and/or threat.


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).


The backbone of a Network refers to infrastructure that interconnects multiple Networks and provides a route for the high-speed exchange of data between different Networks. The backbone can interconnect different Networks of dispersed devices in offices for example. Local Area Networks can be interconnected over a backbone to provide a Wide Area Network.


Applications are computer programs that have a user interface. An application is so named because the program is designed for a specific task or application for the user. Email programs, web browsers and computer games are examples of applications.


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.

Active Directory (AD)

The Active Directory provides information on objects including services, resources and users. The AD allows the control of security settings and access to the objects.