3Com SuperStack 3 NBX, Administrator'S Manual

Page: 42 / 496

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Pretranslator Example 3
Assume that the telephone company passes 4-digit numbers to the
system for each incoming telephone call (for example, numbers in the
range 5200 through 5300). If the system uses 3-digit extensions in the
range 200 through 300, you could define a single pretranslation
operation to
stripLead (remove) the first digit, for instance, the number 5
from an incoming number such as 5278, and pass the call to extension
278. “Sample Solutions Using Dial Plan Configuration File Commands”
later in this chapter shows how to accomplish this pretranslation using
the dial plan configuration file.
Pretranslators for
Certain
Outgoing Calls
On outgoing calls using an ISDN PRI card, pretranslators allow the
external called party to identify the full number of the internal calling
party, including the area code. For example, if the person on extension
101 within a company calls an external number, the caller’s entire number
is displayed to the called party when Calling Line ID Presentation (CLIP)
pretranslators are used. Pretranslation reformats the outgoing dialed
number
before it is passed to the Internal dial plan table (Table ID 1) or
possibly the Least Cost Routing table (Table ID 3). For more information,
see “Internal Dial Plan Table” and “Least Cost Routing Dial Plan Table”
later in this chapter.
Example: If the DDI/DID telephone numbers range from 508-555-4200
through 508-555-4299, internally, you dial extensions from 2000
through 2099 to reach another internal telephone.
When you place a call to an external telephone number, the system can
use these pretranslator steps to create the full 10-digit number:
1 Remove (stripLead) the first two digits (20) from the internal extension
number of the telephone making the call.
2 Add (prepend) the digit sequence 50855542 to the two remaining digits,
creating the full DDI/DID telephone number.
3 Pass the full number to the telephone company.
Example: To transmit Calling Line ID Presentation (CLIP) information on
outgoing calls, you can define a pretranslator that transforms internal
extensions into full telephone numbers (the numbers that someone
external to the company uses to dial in). Assume that you are using
telephone extension numbers from 1000 to 1099 and that only the last
two digits match the DDI/DID (Direct Inward Dial/Direct Dial Inward)
numbers that are assigned to the company. You can define a