A communication cable designed to be placed under the surface of the Earth in a duct system that isolates it from direct contact with the soil.

Cable and wire plant, together with closures appropriate for the application, that is placed below ground in structures such as conduit or ducts. [T1.316-1997]

In facsimile, a defect that occurs when the width of the scanning line is less than the scanning pitch.

See overshoot.

Any signal that tends to produce degradation in the operation of equipment or systems.

Deprecated synonym for undetected error ratio.

The ratio of the number of bits, unit elements, characters, or blocks incorrectly received and undetected, to the total number of bits, unit elements, characters, or blocks sent. Synonyms residual error rate, undetected error rate [deprecated].

A day during which neither sunspot activity nor ionospheric disturbance causes detectable interfere with radio communications.

A code placed in unequipped channels by originating equipment to indicate to path terminating equipment that the channel is intentionally unoccupied so that alarms can be inhibited. [T1.105-1988]

A valid frame that cannot be processed. The frame itself is perfectly legitimate. Its unexpected character is defined by two conditions: the specific type of frame and the state of the receiver. [T1.218-1991] The layer-2 protocol states define the proper sequence in which frames are expected to occur. The receiver will compare received frames with its own protocol state to… (Read More →)