Lucent Technologies Release 6 manual Psc, Psdn, Ptc, Ptt, Qppcn, Qsig, Ram

DEFINITY Enterprise Communications Server Release 6	Issue 5
Installation and Test for Multi-Carrier Cabinets 555-230-112	May 1998
Glossary and Abbreviations
	Page GL-41

protocol

A set of conventions or rules governing the format and timing of message exchanges to control data movement and correction of errors.

PSC

Premises service consultant

PSDN

Packet-switch public data network

PT

Personal terminal

PTC

Positive temperature coefficient

PTT

Postal Telephone and Telegraph

public network

The network that can be openly accessed by all customers for local and long-distance calling.

pulse-code modulation (PCM)

An extension of pulse-amplitude modulation (PAM) in which carrier-signal pulses modulated by an analog signal, such as speech, are quantized and encoded to a digital, usually binary, format.

Q

QPPCN

Quality Protection Plan Change Notice

QSIG

A set of open standards for Enterprise Networking. QSIG is a protocol defining message exchanges (signalling) at the “Q” reference point between two PBXs.

quadrant

A group of six contiguous DS0s in fixed locations on an ISDN-PRI facility. Note that this term comes from T1 terminology (one-fourth of a T1), but there are five quadrants on an E1 ISDN-PRI facility (30B + D).

queue

An ordered sequence of calls waiting to be processed.

queuing

The process of holding calls in order of their arrival to await connection to an attendant, to an answering group, or to an idle trunk. Calls are automatically connected in first-in, first-out sequence.

R

RAM

See random-access memory (RAM).