Designing a Dial Plan to Meet Your Needs
Designing a dial plan that meets your needs sounds pretty fundamental, but what
does it mean? When you implement AVVID, you should work under the assumption
that the less complex it is, the better. Find out what is used on a normal
(daily) basis, and what features are seldom used.With these answers, you can
create a plan that meets the needs of the client.
If you are setting up a branch office, you will probably need to implement a
system similar to this. Company X would like to set up AVVID within their
regional offices. All branch offices will have several levels of call barring that
allow local calls (those calls located within the local exchange only), some that
allow long distance calls, and some that allow international calling. For ease of
demonstration, we will create dial plans that allow for a greater level of granularity
then you might encounter in the real world. By creating a high level of distinction,
you will be able to filter numbers using the local dialing prefix from all
other number combinations.This will help place these router patterns into separate
partitions and calling search spaces (as discussed earlier).This setup allows for
the control of end telephony devices and their ability for outdial access.
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AVVID Dial Plans • Chapter 9 313
NOTE
You will need to alter the dial plan to fit the local numbers where the
CallManager is located. The [ ] wildcards will allow you to specify a range
of numbers, which should reduce the overall number of route patterns
that are comparable.
The United States (and North American) standard for dialing is based on
seven digits for the local exchange area, three digits for the area code, and a
leading one (1) for long distance calls (1 + 425 + (555-5555)).Table 9.8 shows a
basic dial plan.
NOTE
Table 9.8 is not an exhaustive list of all possible call combinations. It is
quite possible there are other numbers that aren’t listed, so please investigate
the particular dial plans associated with your location. Phone
books often have lists of area code and informational/service numbers.