Features
555-230-024
A-52 Issue 5 January 1998
Trunk Group Features
DEFINITY ECS offers an array of features for managing trunk groups efficientl y.

DS1 Trunk Service

Bit-oriented signaling that multiplexes 24 channels int o a single 1.544-Mbps
stream. DS1 can be used for voice or voice-grade data and for data-transmission
protocols. E1 trunk service is bit-oriented signaling that multiplexes 32 channels
into a single 2.048-Mbps stream. Both DS1 and E1 provide a digital int erface for
trunk groups.

Digital Multiplexed Interfa ce

Supports two signaling techniques: bit-oriented signaling and message-oriented
signaling for direct connection to host computers.

ISDN — General

Gives you access to a variety of public and private networ k services and facili-
ties. The ISDN standard consists of layers 1, 2, and 3 of the Open System Inter-
connect (OSI) model. DEFINITY ECS can be connected to an ISDN using
standard frame formats: Basic Rate Interface (BRI) and the Primary Rate Inter-
face (PRI).
An ISDN provides end-to-end digital connectivity and uses a high-speed
interface which provides service-independent access to swi tched services.
Through internationally accepted standard interfaces, an ISDN provides circuit or
packet-switched connectivity within a network and can link to other ISDN
supported interfaces to provide national and international digital conne ctivity.

R6 BRI Trunk Enhancements

Adds support for public-network access outside the U.S. on point-to-midpoint
connections, with the restriction that DEFINITY ECS must not be configu red 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.
BRI: Basic Rate Interface. This standard ISDN interface consists of two 64 Kbps
B-channels and one 16 Kbps D-channel.
ISDN: Integrated Services Digital Network.

NT Interface on TN556C

Support for the NT (network) side of the T interface has been added in R6 using
the TN556C circuit pack, which DEFINITY R5 uses only for v oice and data end-
points. This gives R6 full tie trunk capability using BRI trunks. R6 supports leased