AT&T System 85 Telephone User Manual


 
DEFINITY High Speed Link
Permanent (Private Line) Requirements
The following sections describe Permanent (Private Line) requirements.
Releases for Permanent Applications
Permanent applications require the switch to establish and maintain the connection. The switch
release and corresponding feature that support permanent connections are:
System 75 R1V2 or later - Permanent Switched Call (PSC)
System 85 R2V4 or later - Dedicated Switch Connection (DSC)
Generic 1 - Administered Connection (AC) or Permanent Switched Call (PSC)
Generic 2 - Dedicated Switch Connection (DSC)
Generic 3 - Administered Connection (AC)
These various switch features provide different levels of support for permanent applications.
DEFINITY G3 provides the broadest level of support with the Administered Connection Feature.
The Permanent Switch Call in S75/G1 and the Dedicated Switch Connection in S85/G2 provide a
subset of that functionality.
Permanent Endpoints
If Data Terminal Equipment (DTE) does not support the DTR lead, then the DTR IGNORE option
must be used. This will allow a permanent connection to be established and maintained.
Permanent Applications
A permanent connection uses a DS0 channel on a private T1 between sites, or a DS0 channel on
a DS1 to a private digital network such as ACCUNET Spectrum of Digital Services (ASDS). See
Figure 3 for an example of a Front End Processor/Cluster Controller application in a permanent
connection configuration. For additional information on permanent applications, implementations,
and administration, refer to the
DEFINITY High Speed Link User’s Manual
, 555-020-711, Appen-
dix D: Applications and Switch Administration.
5-59