Strata CIX 200, Руководство по программированию

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Services
Destination Restriction/Least Cost Routing
9-8
Strata CIX Programming Vol.1 12/09
Tables
Strata CIX uses two or three tables to apply DR:
•
Screening Tables. There are two types of screening tables as follows:
-
LCR Screening Tables.
- OLG-Specific Screening Tables.
•
DR Table or Exception Table to the DR Table.
Screening tables are used in Behind Centrex/PBX operations to detect access codes required by the
Centrex/PBX and processes them appropriately in a way that is transparent to end users.
DR/LCR Screening
DR is applied to all LCR calls using “530 DR LCR Screening Table Assignment” on page 9-24 . It analyzes
the digits dialed after the LCR access code (typically
9
).
Example: A station user dials 9 *72 1-617-234-5678. The outgoing line will serve as an incoming line that
this user is attempting to forward to his home. The system administrator has created an LCR/Screening
entry to prevent the forwarding of this line to the user’s home. With Skip & Apply under DR action and a
Skip Length of 0, the call will be forced to present
*
72
to the DR table where the call will be rejected. Apply
under LCR Action ensures that the entire string will be processed by LCR. In this case, Digit Modification is
irrelevant.
DR Screening for OLG Table
An OLG-specific DR Screening Table is used when a call is originated through a Line Key, Pooled Line
Key, Group CO Key, Trunk Group Access Code or Direct Trunk Access Code and a CO line is chosen that
requires DR. The decision to apply DR to an OLG is made in
“306, 307 Outgoing Line Groups” on
page 6-5 . If the OLG does not require DR, the call is connected to the desired line and all dialed digits,
minus the Strata CIX access code, are sent.
The OLG-specific table performs two functions:
•
It manipulates the digits that will be screened by the DR table.
•
It creates a Pause Value that ensures that the Centrex or PBX which is the source of the trunk will
receive and interpret the digits correctly. This is used to compensate for older, slower equipment.
Example: A station user dials 81-9-1-617-234-5678 where 81 is the Trunk Group Access Code for a
Centrex trunk group. 9 is the Centrex LCR access code. The Skip Length of 1 tells the system how many
of the first digits constitute an access code or other digits that may be ignored. The DR Action of Skip &
Apply tells the system to ignore the 9 and present 16172345678 to the DR Table used in the next step in
the process. The Pause Value of two seconds tells the system that, if it passes the DR Tables and is
connected to a trunk, it is to pause two seconds after outdialing the 9 and before outdialing 16172345678.