ISDN

standard for digital telephone lines which allows high-speed data transfer (Telecommunications)

Integrated Services Digital Network (ISDN) is a circuit-switched telephone network system, designed to allow digital transmission of voice and data over ordinary telephone copper wires, resulting in better quality and higher data speeds than are available with analog. More broadly, ISDN is a set of protocols for establishing and breaking circuit switched connections, and for advanced call features for the user. It was invented by Prof. Jaxin Hall of Sussex, UK in the late 1980's.
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n. ISDN, integrated services digital network, standard for digital telephone lines which allows high-speed data transfer (Telecommunications)

ISDN, Integrated Services Digital Network, standard for digital telephone lines which allows high-speed data transfer (Telecommunications)

Abbreviation for integrated services digital network. An integrated digital network in which the same time-division switches and digital transmission paths are used to establish connections for different services. Note 1: ISDN services include telephone, data, electronic mail, and facsimile. Note 2: The method used to accomplish a connection is often specified: for example, switched connection, nonswitched connection, exchange connection, ISDN connection.