G 
data link
Any serial data communication transmission path, generally between two adjacent nodes or devices and without any intermediate switching nodes.
data link layer
In the OSI model, the network processing entity that establishes, maintains and releases data link connections between adjacent elements in the network.
DCE (Data Circuit-Terminating Equipment)
Equipment that is either a part of the network, an access point to the network, a network node, or equipment at which a network circuit terminates.
dial-up
Describing the process of, or the equipment or facilities involved in, establishing a temporary connection via the switched telephone network.
digital loopback
A technique for testing the digital processing circuitry of a communications device; may be initiated locally or remotely via a telecommunications circuit. The device being tested returns a received test message, the results of which are compared to the original message.
DS-0 (Digital Signal Level 0)
A 64kbit/s standard digital telecommunications signal or channel.
DS-1 (Digital Signal Level 1)
The 1.544Mbit/s digital signal carried on a T1 facility.
DS-3 (Digital Signal Level 3)
The 44.736Mbit/s digital signal carried on a T3 facility.
DSU/CSU (Data Service Unit/Channel Service Units)
The pair of communications devices that connect an
DSU (Data Service Unit)
A device designed to connect a DTE to a digital phone line. The DSU transmits and receives the signal and provides buffering and flow control. The DSU and CSU are often in the same unit. Also called a Digital Service Unit.
DSR (Data Set Ready)
A data port signal.
Glossary |
