AT&T DS1/DMi/ISDN-PRI manual Ops Opx, Digital Network primary rate interface, Glossary GL-15

GLOSSARY GL-15

network synchronization plan

nonfacility associated signaling (NFAS)

off-premises extension (OPX)

off-premises station (OPS)

ones density

OPS

OPX

out-of-band signaling

packet

packet assembler/ disassembler (PAD)

An engineering diagram that identifies each customer-premises switching node and specifies how each switching node is to obtain synchronization. Depending on the distribution of work, either the controlling Regional Engineering Center (REC) or the National Engineering Center (NEC) will provide the network synchronization plan.

A method that allows multiple T1 links to share a single D-channel on one of the spans to form an Integrated Services Digital Network primary rate interface (ISDN-PRI). One T1 link is therefore configured as 23 B-channels plus 1 D- channel, while the other spans that share the D-channel are configured with 24 B-channels each. See also facility-associated signaling and Integrated Services

Digital Network primary rate interface.

A trunk-side analog telephone line that has several capabilities not normally available to telephone lines. Among these are a collection of call-detail records and traffic data that are needed on telephone lines used to access host computers, and certain transmission characteristics desired for long-range, off-premises operation. See also off-premises station.

A device that provides service between a communications system and a single- line analog telephone located beyond the normal communications-system analog-line signaling range. See also off-premises extension.

1.The requirement for digital transmission lines in the public network that eight consecutive 0s cannot be in a digital data stream.

2.A technique for inserting a 1 after every seventh-consecutive 0.

See also zero code suppression.

See off-premises station.

See off-premises extension.

Signaling that uses the same path as voice-frequency transmission and in which the signaling is outside the band used for voice frequencies See also Integrated Services Digital Network basic rate interface and Integrated Services Digital

Network primary rate interface.

A group of bits — including a message element, which is the data, and a control information element (IE), which is the header — used in packet switching and transmitted as a discrete unit. In each packet, the message element and control IE are arranged in a specified format. In many systems, the packet is further encapsulated with additional header and trailer elements to form a frame. See also packet switching.

A functional unit that enables data terminal equipment (DTE) not equipped for packet switching to access a packet-switched network.