Technical information

MERLIN II Communications System
Issue 7 June 2001
5-5
MERLIN II Communications System
This section provides information on protecting the MERLIN II Communications
System.
Additional security measures are required to protect adjunct equipment.
 Chapter 6 contains security measures to protect the attached voice
messaging system. For general security measures, refer to ‘‘Protecting
Voice Messaging Systems’’ on page 6-2. For product-specific security
measures, refer to ‘‘MERLIN II Communications System’’ on page 6-34.
 Chapter 7 contains security measures to protect the Automated Attendant
feature of your communications system. See ‘‘MERLIN II Communications
System R3’’ on page 7-19.
Protecting Direct Inward System Access (DISA)
The Direct Inward System Access feature allows users to call into the MERLIN II
Communications System from a remote location (for example, a satellite office, or
while traveling) and use the system to make calls. However, unauthorized
persons might learn the DISA telephone number and password, call into the
system, and make long distance calls.
The following security measures assist you in managing the DISA feature to help
prevent unauthorized use.
Security Tips
 To reduce the system’s vulnerability to toll fraud, outward restrict the port to
which the Remote Maintenance Device is connected.
 Evaluate the necessity for DISA. If this feature is not vital to your
organization, consider not using it or limiting its use.
To restrict DISA lines, do the following:
— With a BIS-34D Console:
1. Move the TP switch to P.
2. Press the conference button twice.
3. Press the message button.
4. Dial #325.
5. Dial 0 for Outward Restriction.
6. Press the message button again.