AT&T MERLIN LEGEND Release 3.1 System Manager's Manual page 159

Features
When you change your system, be aware of the following special considerations
that apply to toll calling:
The Remote Access feature allows employees to dial into the system by
dialing the number of a trunk designated for remote access. After a
remote access caller reaches the system, you should make sure that he
or she must dial a password (called a barrier code ). After gaining access
to the system, the user can, among other things, select a regular or
special-purpose outside line (for example, a WATS line) or a pool or an
ARS line to make outgoing calls. You can apply calling restrictions to
outside lines used to access the system remotely; you can also apply
restrictions to barrier codes just as though they were system extensions.
Some voice messaging systems (described later in this chapter) permit
outcalling . That is, these systems can be programmed to call an outside
number to deliver messages or faxes. This feature can be used for toll
abuse, so consider calling restrictions for lines used by such systems.
Remote Call Forwarding can be allowed or disallowed for your system. If
allowed, a user can have calls forwarded to an outside number. (This is
not permitted at extensions or on lines where calling restrictions have
been applied.)
When restrictions are applied to extensions, rather than to lines/trunks, a
person can ask a co-worker or operator with fewer restrictions to make a
toll call on his or her behalf.
Authorization codes are intended to allow people with less restricted
extensions to use extensions where there are more restrictions. If you use
authorization codes to enforce restrictions, people may discover that, at
some extensions, they can make calls without using authorization codes
and gain more privileges than their own extensions allow.
The sections below list the types of restrictions, including the following
information:
Whether the restriction is applied to an extension, line, remote access
barrier code (acting as an "extension" for a remote access user), or a
combination
What other restriction features it works in conjunction with, as well as
mode restrictions
A brief description, including recommended use
Since there is some interaction among these features and with other system
features, refer to the Feature Reference for more detailed information .
Features and Applications
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