Lucent Technologies 5 User Manual

Page of 429
MERLIN LEGEND Communications System Release 5.0
System Manager’s Guide  
555-650-118  
Issue 1
June 1997
Customer Support Information 
Page A-9
Toll Fraud Prevention 
A
To minimize the risk of unauthorized access to your communications system:
Use an unpublished Remote Access number.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 Access 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.