An off-hook condition applied to the network interface (NI) by the network that indicated the network intends to complete a call attempt to the customer installation (CI) or intends to continue an established connection. [T1.208-1989]

Those aspects of the rules used in the formal specification of data that embody a specific representation of those data. [T1.208-1989]

1. Synonym multitasking.
2. In data link operations, the operation in which two or more data links are used during the same, usually short, time interval, while adhering to the protocols of each link without providing data forwarding among the links.

A mechanism that is used to protect and control the viewing of traditional broadcast TV content, on-demand content, and pay-per-view. It has been implemented over uni-directional and bi-directional networks and co-channel transport. It is used both in analog TV broadcast systems and in digital TV delivery systems (where the equivalent of analog de-scrambling for digital services is implemented).

Synonym non-return-to-zero mark.

A communications circuit optimized to obtain desired characteristics for voice or data transmission.

A form of diphase modulation, combined with signal conditioning, that (a) eliminates the dc component of the signal, (b) enhances timing recovery, and (c) facilitates transmission over voice frequency (VF) circuits or coaxial cables.

A loop that has conditioning equipment to obtain the desired line characteristics for voice or data transmission.
Note: The conditioning equipment is used to improve the amplitude-vs. -frequency characteristics of the circuit and to match impedance.

1. At junctions of circuits, equipment used to obtain desired circuit characteristics, such as matched transmission levels, matched impedances, and equalization between facilities.
2. Corrective networks used to improve data transmission, such as equalization of the insertion-loss-vs. -frequency characteristic and the envelope delay distortion over a desired frequency range.

1. Interference resulting from noise or unwanted signals entering a device by conductive coupling, i.e., by direct coupling.
2. An undesired voltage or current generated within, or conducted into, a receiver, transmitter, or associated equipment, and appearing at the antenna terminals.