Lucent Technologies 5 manual Information, see ‘Authorization‘Codes’’ on

MERLIN LEGEND Communications System Release 5.0	Issue 1
System Manager’s Guide 555-650-118	June 1997

4Features and Applications

Features Page 4-41

special services from the CO. For example, in many areas a telephone user can dial *67 before a telephone number to disable central office-supplied caller identification at the receiving party’s telephone. (To allow or disallow star codes

preceding a call, see ‘Revising‘ Allowed Lists’’ on page 6-69 or ‘‘Revising Disallowed Lists’’ on page 6-72.)

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 causes the system to prevent the call when digits are entered during the pause.

In Behind Switch mode, calling restrictions must be supplied by the host system, not by the MERLIN LEGEND Communications System.

In Release 3.1 and later systems, the system provides certain default calling restrictions that make it easier for system managers to guard against toll fraud. These are described below with the specific features they affect.

This section describes each type of calling restriction. Some of these features are combined with security measures to prevent system abuse by remote access users or hackers. In addition, users can be assigned authorization codes, which they can enter when they are away from their extensions. When a person enters an authorization code while visiting another system extension, the calling restrictions assigned to his or her own extension are applied to the call. For more

information, see ‘Authorization‘Codes’’ on page 4-46.

!SECURITYlALERT:

For more information see the section, ‘‘Security’’ on page 4-47. Also consult

‘Security‘ of Your System: Preventing Toll Fraud’’, in Appendix A, ‘‘Customer Support Information’’.

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.