214 CHAPTER 3: DEVICE CONFIGURATION
request a specific range of numbers, but sometimes the carrier assigns
numbers other than the ones you request.
You may be able to request that the local telephone carrier pass you a
specific number of digits for each incoming telephone call. Sometimes
the carrier does not offer any choice. In either situation, you need to
know how many digits the carrier passes.
Example: Carriers commonly pass either the last three digits or last four
digits of the number for each incoming call.
Sometimes the last digits of the telephone numbers the carrier assigns to
you do not match the telephone extension numbers you want to use for
internal calls. Create entries in your Dial Plan configuration file to trans-
late the incoming numbers into the corresponding extension numbers.
Example: You want to use internal extensions from 4000 through 4999,
but the local telephone carrier assigns you numbers from 617-555-3500
through 617-555-4499. You can create translator entries in the Dial Plan
configuration file to translate an incoming digit sequence such as 3795
into extension number 4295, and a sequence such as 4213 into 4713.
The configuration would require several translator entries to handle
subsets of the total range. A unique set of entries would handle incoming
digit sequences from 3500 through 3599, from 3600 through 3699, and
each of the other sequences in which the first two digits were unique in
the range from 37XX through 44XX.
If the DDI/DID numbers match your internal extension numbers, the
translator entries in your Dial Plan configuration file can be much simpler.
Example: You plan to use internal extensions from 100 through 299,
and the local telephone company assigns you numbers from
617-555-4100 through 617-555-4299. If the local telephone carrier
passes you three digits, you need no translator entries in the Dial Plan
configuration file. If the carrier passes you four digits, you could add a
single set of translator entries to the configuration file to remove the first
digit (4) and use the remaining three digits as the internal extension.
Enabling Auto Discovery for Digital Line Cards
To enable Auto Discovery for Digital Line Cards:
1Select NBX NetSet > System Configuration > System Settings.
2Click the Auto Discover Digital Line Cards check box.