Digital information transferred across the functional interface between a user and a telecommunications system, or between functional units within a telecommunications system, for the purpose of directing or controlling the transfer of user information or the detection and correction of errors.
Note: Overhead information originated by the user is not considered to be system overhead information. Overhead information generated within… (Read More →)

An arrangement for exchange-carrier-to-interexchange carrier (EC-to-IC) outpulsing that allows seizure of the EC-to-IC trunk and initiation of outpulsing prior to completion of dialing by the calling customer. [T1.104-1988]

1. One of several segments of a computer program that, during execution, occupies the same area of main storage, one segment at a time.
2. To use repeatedly the same areas of internal storage during different stages of the execution of a program.

A larger cell that physically overlays one or more smaller cells. For example, intra-building cells may be encompassed by a larger campus cell. [T1.244-1995]

A load, placed on a device or facility, that is greater than the device or facility is capable of handling, i.e., capable of performing the functions for which it was designed.
Note: Examples of overloads are (a) traffic on a communications system greater than the traffic capacity of the system, (b) for analog inputs, voltage levels above which an analog-to-digital… (Read More →)

Synonym load capacity.

1. The condition that prevails when the instantaneous level of the modulating signal exceeds the value necessary to produce 100% modulation of the carrier.
Note 1: Overmodulation results in spurious emissions by the modulated carrier, and distortion of the recovered modulating signal.
Note 2: Overmodulation in the sense of this definition is almost always considered a fault condition.
2. The… (Read More →)

1. To preempt, manually or automatically, a prescribed procedure.
Note: For example, one might manually override a prescribed course of action programmed to occur in the event of a fault.
2. In telephony, the entering of or seizure of, a busy circuit, i.e., an occupied circuit, by a party other than those using the circuit.
Note: For example, an attendant… (Read More →)

1. In the transition of any parameter from one value to another, the transitory value of the parameter that exceeds the final value.
Note: Overshoot occurs when the transition is from a lower value to a higher value. When the transition is from a higher value to a lower value, and the parameter takes a transitory value that is lower… (Read More →)

[A] Communications path within a computer system or network designed for the authorized transfer of data. [INFOSEC-99]