Instruction manual

DEFINITY® Business Communications System and GuestWorks® Issue 6
Overview
555-231-208
Issue 1
April 2000
Networking Solutions
9-11ISDN
9
PRI, referred to as 23B + D or 30B + D on an E1 interface, uses 23 or 30 64 kbps
B channels and one 64 kbps D channel. The 23 or 30 B channels can be used
for 23 or 30 individual voice or data calls. BRI, referred to as 2B + D, uses two 64
kbps B channels and one 16 kbps D channel. The B channels give the user simul-
taneous voice and data transmission over the same connection. This channel
architecture allows full and complete use of the 64 kbps B channels from end
point to end point for information movement managed by signaling messages,
called Q.931 messages, in the D channel.
To help your business achieve maximum benefits from ISDN and the public net-
work, the following features reside within the ISDN service nodes:
■ Call-by-Call Service Selection lets you reach multiple services via the same
ISDN B channel. Therefore, a channel can be allocated among
MEGACOM Wide Area Telecommunications Service, MEGACOM 800/888
Service, and other services on a dynamic basis, eliminating the need for
dedicating each truck or channel to a specific service.
■ Automatic Number Identification, marketed as Information Forwarding-2
(INFO-2), is available on MEGACOM 800/888 Service. INFO-2 delivers the
originating calling party’s billing number to your system.
■ Station Identification Number, similar to INFO-2, identifies the calling party
number behind the system. Station Identification delivers the originating
caller’s telephone number to the network where it is sent to the terminating
location.
■ User-to-User Information sends user information from one endpoint to
another using the D channel. Three forms are available: message
associated data, sent within Q.931 call control messages during call
establishment and call clearing; call-associated data, sent during call setup
on a B channel; and noncall-associated data, sent with no related
call-setup activity on the B channel. Applications for this feature include
display of calling party name and number.
The system’s support of ISDN-PRI, ISDN-BRI, and available public network ser-
vices means that you can achieve full end-to-end ISDN connectivity and take
advantage of ISDN services and features. For example, two systems connected
by PRI can exchange calling party name and/or number information. The informa-
tion is displayed on the called party’s telephone. In addition, the called party’s ID
is also displayed at the calling party’s telephone. This lets users identify the
source of an incoming call before answering. Computer telephone integration
interfaces can also use the information provided by the network to integrate your
communications and data-processing systems.