Nortel BCM 3.7, Manual

Page: 358 / 1004

358 Defining restriction filters
N0008589 3.3
Removing restrictions
To remove restrictions that no longer apply, click on the Restriction # you want to remove, then
click the
Delete button at the top of the column.
Exercise caution when removing overrides.
If you remove a restriction, the overrides associated with the restriction are also removed. This
action also changes the identifying numbers of the subsequent restrictions that you have defined.
For example, if you remove Restriction 01, Restrictions 02 to 08 are renumbered as 01 to 07.
Notes about restriction filters
A restriction filter is a group of restrictions and overrides that specify the external numbers or
feature codes that cannot be dialed from a telephone or on a line. The restriction filters setting
allows you to assign restrictions in one step as a single package of dialing sequences that are not
permitted.
In addition to restricting telephone numbers, you can prevent people from entering dialing
sequences used by the central office (the public network) to deliver special services and features.
Some of these features provide the caller with dial tone after they have entered the special code
(which often uses # or *), therefore, users have an opportunity to bypass restrictions. To prevent
this from happening, you can create filters that block these special codes.
You create a filter by defining the dialing sequences that are denied. There are also variations of
each sequence that you want users to be able to dial, these are called overrides. Overrides are
defined within each restriction package for each filter.
Once you create the filters, you can assign the restrictions to a telephone ( System DNs ), to a line
( Lines ), to a particular line on a telephone ( System DNs ), and to remote callers
( Lines, Remote access ).
Note: Filter 00 cannot be changed. Filter 01 has a set of defaults. Filters 02 to 99 can be set to suit
your special requirements. See “Default filters (North America)” on page 359 .
• Each programmable filter can have up to 48 restrictions.
• There is no limit on the number of overrides that can be allocated to a restriction. However,
there is a maximum total of 400 restrictions and overrides allocated to the 100 programmable
filters.
• The maximum length of a restriction is 15 digits.
• The maximum length of an override is 16 digits.
• Entering the letter A in a dialing sequence indicates a wild card, and represents any digit from
0 to 9.
• You can use * and # in a sequence of numbers in either a restriction or an override. These
characters are often used as part of feature codes for other systems or for features provided by
the central office (the public network).