Instruction manual

DEFINITY® Business Communications System and GuestWorks® Issue 6
Overview
555-231-208
Issue 1
April 2000
Glossary and Abbreviations
GL-18
IDF
Intermediate distribution frame
immediate-start tie trunk
A trunk on which, after making a connection with a distant switching system for an outgoing call, the
system waits a nominal 65 ms before sending the digits of the called number. This allows time for
the distant system to prepare to receive digits. On an incoming call, the system has less than 65 ms
to prepare to receive the digits.
INADS
Initialization and Administration System
incoming gateway
A PBX that routes an incoming call on a trunk
not administered for Supplementary Services
Protocol B to a trunk
not administered for Supplementary Services Protocol B.
information exchange
The exchange of data between users of two different systems, such as the switch and a host
computer, over a LAN.
INS
ISDN Network Service
inside call
A call placed from one telephone to another within the local communications system.
Integrated Services Digital Network (ISDN)
A public or private network that provides end-to-end digital communications for all services to which
users have access by a limited set of standard multipurpose user-network interfaces defined by the
CCITT. Through internationally accepted standard interfaces, ISDN provides digital circuit-switched
or packet-switched communications within the network and links to other ISDNs to provide national
and international digital communications. See also Integrated Services Digital Network Basic Rate
Interface (ISDN-BRI) and Integrated Services Digital Network Primary Rate Interface (ISDN-PRI).
Integrated Services Digital Network Basic Rate Interface (ISDN-BRI)
The interface between a communications system and terminal that includes two 64 kbps
B-channels for transmitting voice or data and one 16 kbps D-channel for transmitting associated
B-channel call control and out-of-band signaling information. ISDN-BRI also includes 48 kbps for
transmitting framing and D-channel contention information, for a total interface speed of 192 kbps.
ISDN-BRI serves ISDN telephones and digital terminals fitted with ISDN terminal adapters. See
also Integrated Services Digital Network (ISDN)
and Integrated Services Digital Network Primary
Rate Interface (ISDN-PRI).
Integrated Services Digital Network Primary Rate Interface (ISDN-PRI)
The interface between multiple communications systems that in North America includes 24 64 kbps
channels, corresponding to the North American digital signal level-1 (DS1) standard rate of 1.544
Mbps. The most common arrangement of channels in ISDN-PRI is 23 64 kbps B-channels for
transmitting voice and data and one 64 kbps D-channel for transmitting associated B-channel call
control and out-of-band signaling information. With nonfacility-associated signaling (NFAS),
ISDN-PRI can include 24 B-channels and no D-channel. See also Integrated Services Digital
Network (ISDN) and Integrated Services Digital Network Basic Rate Interface (ISDN-BRI).
intercept tone
An alternating high and low tone that indicates a dialing error or denial of the service requested.
internal call
A connection between two users within a system.