Instruction manual

DEFINITY® Business Communications System and GuestWorks® Issue 6
Overview
555-231-208
Issue 1
April 2000
Features
A-49Trunk Group features
A
Transit Counter
The system provides QSIG Transit Counter as defined in ISO/IEC 6B032
and 6B033. It prevents indefinite looping, connections giving poor transmission
performance, and inefficient use of network resources. This feature is invoked
automatically for ISDN-PRI basic calls.
Uniform Dial Plan
Provides a common four- or five-digit dial plan that can be shared among a group
of switches. Both interswitch and intraswitch dialing require four- or five-digit
dialing. This feature is used with an electronic tandem network (ETN).
Trunk Group features
The system supports a variety of interfaces to voice and data networks. Trunks
supply links between the system, the public network, and other systems. Digital
Signal Level 1 interfaces offer high-speed digital connectivity between systems.
For a complete listing of the trunk and line interfaces available in different
countries, see the
DEFINITY
®
ECS System Description .
Automatic TEI
The user side will support automatic TEI assignment by the network. Both fixed
and automatic TEI assignment are supported on the network side.
BRI Trunk Service
Supports public-network access outside the U.S. on point-to-midpoint
connections, with the restriction that the system must not be configured in a
passive bus arrangement with other BRI endpoints. It will also support the use of
ISDN-BRI trunks as inter-PBX tie lines using the QSIG peer protocol. The system
supports a two-wire U interface, the four-wire T interface, and the U.S. National
ISDN protocol.
Call-by-Call Service Selection
Enables a single ISDN-PRI trunk group to carry calls to a variety of services,
rather than requiring each trunk group to be dedicated to a specific service. It
allows you to set up various voice and data services and features for a particular
call.