D
D channel

See delta channel (D channel).

daemon

Pronounced "demon," a program that acts like a terminate-and-stay-resident (TSR) application by loading into memory and lurking there for any trigger that calls on its services.

data communication equipment (DCE)

Equipment that provides clocking to DTE equipment. DCE equipment starts at the CSU/DSU and is defined as a connection all the way to the providers network.

Data Encryption Standard (DES)

A deprecated cryptographic block cipher that falls to brute-force attacks due to its short 56-bit key. Triple DES (3DES), which was widely used before AES became a standard, is a block cipher formed from the DES cipher by using it three times.

data frame

A frame is the Protocol Data Unit encapsulation ...

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