AT&T MERLIN LEGEND Release 3.1 System Manager's Manual page 165

Features
Security
Most security issues were covered in the section above, "Calling Restrictions,"
which describes the various ways you can help guard against toll fraud. There
are four additional features you can use to enhance security and make phone
use easier for people in your company:
Barrier Codes. Barrier codes are unique passwords assigned to remote
access users, and are designed to prevent unauthorized individuals from
using the system. As noted above, you can also apply calling restrictions
to barrier codes. Change barrier codes frequently and immediately
deactivate any unused barrier codes. In Release 3.1 and later systems
(Hybrid/PBX only), remote access barrier codes are restricted, by default,
from making outside calls.
IMPORTANT:
Read the "Security Alert" at the end of this chapter before using this
feature.
Disabling Trunk-to-Trunk Transfer. In Release 3.1 and later systems,
extensions are, by default, not allowed to make trunk-to-trunk transfers,
that is, to transfer an outside caller to another outside line/trunk. This
enhancement helps secure against toll fraud. To change the trunk-to-
trunk transfer privileges of an extension, see Chapter 6, "Managing the
System."
Star-Code Dialing Pause. In Release 3.1 and later systems, a system
programming feature allows you to help guard against toll fraud when
star codes are dialed under certain circumstances. Star codes, typically
dialed before an outgoing call, provide special services from the CO. For
example, in many areas a telephone user can dial
number to disable central office-supplied caller identification at the
receiving party's telephone (to allow or disallow star codes preceding a
call, see Chapter 6, "Managing the System"). Some central offices supply
a second dial tone following the dialed star (*) code, to signal customers
that they must dial additional digits. If this second dial tone is not
immediate, a hacker can enter digits that are not detected by the CO but
are detected by the system's calling restrictions. If your business uses
central office star codes and the CO issues a second dial tone after a
pause, see System Programming for information about including a timed
delay that will cause the system to prevent the call when digits are
entered during the pause.
Station Message Detail Recording (SMDR). This system management
feature keeps track of incoming and outgoing calls and prints out reports
on a printer attached to your control unit. It also prints programming
reports that can alert you to tampering with the system. Inspect these
reports frequently. (Call Accounting System applications also provide a
utility for detecting toll fraud. See Table 4–12 later in this chapter.)
before a telephone
Features and Applications
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