AT&T DS1/DMi/ISDN-PRI manual Pad, Pam Pc/Pbx, Pcm Pdm Pds, Pri

GL-16GLOSSARY

packet-switched transport mode

packet switching

packetized data

PAD

parameterized- service format

partitioning

PAM

PC/PBX

Connection

PCM

PDM

PDS

preferred call reference

premises distribution system (PDS)

PRI

The condition in which a communications system or network provides packet switching of the user’s data. See also circuit-switched transport mode.

NOTE: Although the ISDN protocol defines the Packet Switched Transport Mode and the Generic 2 administration software provides for this transport mode

— the switch hardware does not currently include a packet interface.

A data transmission technique whereby user information is segmented and routed in discrete data envelopes called packets, each with its own appended control information for routing, sequencing, and error checking. Packet switching allows a channel to be occupied only during the transmission of a packet; on completion of the transmission, the channel is made available for the transfer of other packets. See also BX.25, packet, and X.25.

The digital multiplexed interface (DMI) mode-3 data-channel protocol used in virtual-circuit service for the statistical multiplexing of data streams. See also

LAPD Packetized Data.

See packet assembler/disassembler.

One of two network-specific facility (NSF) service types that are administered in conjunction with the Automatic Alternate Routing/Automatic Route Selection (AAR/ARS) routing patterns. The parameterized service format requires multiple bytes to convey all the necessary information about the requested service or facility. See also binary service format.

The capability to impose restrictions on each tenant’s users to limit their access to only a specified subset of the communications system’s facilities and services. Partitioning allows a multitenant system to comply with state or federal regulations and to provide security and cost allocation between tenants. See also

tenant service.

See pulse-amplitude modulation.

AT&T communications-management software for the MS-DOS®and UNIX® operating systems that integrates a digital multifunction telephone and a PC with a communications system via a Digital Communications Protocol (DCP) interface to provide enhanced voice and data communications services.

See pulse-code modulation.

See processor data module.

See premises distribution system.

See channel negotiation.

A cabling system that consolidates wiring for a customer’s on-site and remote telephones and data terminals, and channels transmissions to the communications system.

See primary rate interface.