MERLIN LEGEND Communications System Release 6.0
System Programming
555-660-111 Issue 1
February 1998
Customer Support Information
PageA-10Toll Fraud Prevention
A
To minimize the risk of unauthorized access to your communications system:
■Use a nonpublished Remote Access number.
■Assign access codes randomly to users on a need-to-have basis, keeping
a log of
all
authorized users and assigning one code to one person.
■Use random-sequence access codes, which are less likely to be easily
broken.
■Use the longest-length access codes the system will allow.
■Deactivate all unassigned codes promptly.
■Ensure that Remote Acces s users are aware of their responsibility to keep
the telephone number and any access codes secure.
■When possible, restrict the off-network capability of off-premises callers,
using calling restrictions, Facility Restriction Levels (Hybrid/PBX mode
only), and Disallowed List capabilities. In Release 3.1 and later systems, a
prepared Disallowed List (number 7) is provided and is designed to prevent
the types of calls that toll-fraud abusers often make.
■When possible, block out-of-hours calling.
■Frequently monitor system call detail reports for quicker detection of any
unauthorized or abnormal calling patterns.
■Limit Remote Call Forwarding to persons on a need-to-have basis.
■Change access codes every 90 days.
■Use the longest-length barrier codes possible, following the guidelines for
passwords. (See “Choosing Passwords.”)
Toll Fraud Prevention 1
Toll fraud is the unauthorized use of your telecommunications system by third
parties to make long distance telephone calls. Under the law, you, the customer,
are responsible for paying part or all of those unauthorized calls. Thus, the
following information is of critical importance.
Unauthorized persons concentrate their activities in two areas with the MERLIN
LEGEND Communications System:
■They try to transfer out of the MERLIN LEGEND Communications System
to gain access to an outgoing trunk and make long-distance calls.
■They try to locate unused or unprotected mailboxes and use them as drop-
off points for their own messages.
The following is a discussion of how toll fraud is often perpetrated and ways to
prevent unauthorized access that can lead to toll fraud.