Lucent Technologies 8.2 User Manual

Page of 1707
DEFINITY ECS Release 8.2
Administrator’s Guide  
555-233-506  
Issue 1
April 2000
Screen reference 
738
ISDN trunk group 
17
Related topics
Refer to DEFINITY ECS Administration for Network Connectivity for 
administration procedures.
Refer to 
‘‘IP trunk service’’ on page 1383
 for detailed information on this feature.
ISDN trunk group
This screen assigns an Integrated Services Digital Network (ISDN) trunk group 
that supports the ISDN and Call-by-Call Service Selection service selection 
features. The trunk group provides end-to-end digital connectivity and supports a 
wide range of services including voice and non-voice services, to which users 
have access by a limited set of CCITT-defined, standard multipurpose interfaces.
The ISDN trunk group may contain ISDN-PRI or ISDN-BRI interfaces. However, 
it is not possible to use the two types of interfaces in the same trunk groups. The 
type of interface is chosen when the trunk members are assigned to the trunk 
group.
When ISDN-PRI interfaces are used on ISDN trunk groups, they may also be used 
to support the Wideband Switching feature. This is intended to work with the H0 
(384 Kbps), H11 (1536 Kbps), H12 (1920 Kbps), and NXDS0 (128 to 1984 Kbps) 
data services, and to support high-speed video conferencing and data applications.
Administration commands
When an ISDN trunk connects two switches, set the trunk options identically at 
both ends of the connection, with the exception of the Trunk Hunt fields. When 
ISDN-PRI interfaces are used, it is acceptable for both ends to have the  Trunk 
Hunt fields administered as 
cyclical
, but if one end is administered as 
ascend
, the 
other end must be administered as 
descend
. This helps avoid the possibility of 
glare conditions. When ISDN-BRI is used, the Trunk Hunt field has to be 
cyclical
.
Hardware requirements
ISDN-BRI interfaces are supported by the TN2185 Trunk-side BRI circuit pack 
(for implementing the user side of the BRI interface) and by the TN556B or 
TN556C ISDN-BRI Line circuit pack or the TN2198 ISDN BRI (U-LT) Line 
circuit pack (for the network side of the BRI interface). The TN2464 circuit 
supports T1 and E1 digital facilities.