Table of Contents
Advertisement
PTS-to-PRI call
The DMS-250 switch may receive the ANI from the following originating
agencies:
FGB
FGD
centralized automatic message accounting
PRI delivers pseudo-ANI for FGC trunks.
If PRI termination from these agencies is required, the following rules for
calling number delivery are applied, depending on the CPIALLOW value in
table CALLATTR for the terminating PRI:
CPIALLOW = YES
— Because the presentation indicator and screening indicator are not
available for these types of agencies, the switch sets the presentation
indicator to the subscription default value presentation allowed and
screening indicator to user-provided, not screened.
— The ANI number without the information digits is outpulsed in the
SETUP message to the terminating PRI.
— Note that the ANI is delivered to the terminating PRI only for calls
that generate a CDR.
CPIALLOW = NO
— The ANI number is not passed to the terminating PRI.
If the calling number is not available due to interworking with a PTS trunk,
the calling number information element is not sent over the outgoing PRI
interface. This means that the presentation indicator and screening indicator
fields are also not delivered.
SS7 network interworking
Upon receiving an ALERT message from the terminating PRI, the DMS-250
switch sends an ACM message with the Backward Call Special Indicator
(BCSI) parameter. The BCSI is typically sent in the ACM, but if an ACM is
not sent (because of fast answer, for example), then the BCSI is sent in the
ANM.
The following values are coded in the BCSI to indicate the calling number
delivery status:
00 = No calling number is delivered (default)
01 = Calling number is delivered
Digital Switching Systems DMS-250 ISDN Reference Manual MWC14 (CSP14)
Feature interaction 7-25
Advertisement
Table of Contents
