| Word | Description |
| Dark Fibre | An optical fibre can be thought of as a very small tube through which light can be sent over long distances. Electronics and lasers are needed to generate the light at one end of the fibre; equipment at the other end of the fibre receives the light and converts it back into electrical energy. It is the equipment at either end of the fibre that dictates what capacity can be delivered over the fibre – ranging upwards from about 100mbps (at the low end). The term ‘dark fibre’ simple refers to optical fibre that is provided without any equipment at either end. Users must provide their own equipment, but they have the flexibility to drive the fibre at whatever speed is desired. |
| Database | An organised collection of information stored on a computer. Databases can be used to store customer contact details, stock/inventory details or customer orders. |
| Database management system (DBMS) | A computer program for organising a database that provides the operations necessary to manage data. |
| Digital cash | A monetary system whereby online currency is used to purchase goods and services in small amounts. The credit is stored on your computer and updated every time you make a purchase over the Internet. |
| Digital signature | A unique electronic signature that is used to authenticate electronic documents and transactions and to ensure that documents have not been tampered with. |
| Digital watermark | An encryption that is embedded in an electronic document and used to identify ownership or authenticate a document. |
| DNS (Domain Name Service) | A server that is used to convert a domain name (for example www.tecc.com.au) into an IP address. |
| Domain | Part of the Internet address structure. The address customers use to find you in the Internet. For example www.tecc.com.au. |
| Download or downloading | The process of copying computer files from the Internet to your own computer. |
| DSL (digital subscriber line) | A technology that is used for bringing high-bandwidth information to private residents and small businesses through the use of ordinary copper telephone wires. |
| DSLAM | DSL Access Multiplexer. This is a unit of electronics that aggregates traffic from multiple customer loops onto a backhaul circuit. DSLAMs come in many different shapes and sizes, ranging from large rack-mounted units that can accommodate many plug-in line cards, to small pizza-box sized units designed for location in street cabinets, building basements and the like. |