Instruction manual

Small business communications systems
6-6 Issue 9 May 2003
— With a MERLIN II Communications System display console:
1. From the administration menu, press these buttons:
Lines
DISA.
2. If callers must dial a password to make DISA calls, dial a
4-digit password.
3. Press
Enter.
4. Press
NoRestr for no restriction, or InwdOnly for inward
restriction.
5. Press the line buttons until the lights next to them show the
appropriate code:
Green light on = line or line pool can be used for DISA
Green light off = line or line pool cannot be used for DISA
6. Press
Conference to return to the administration menu or
leave administration mode.
If you need the feature, use as many of the security measures presented in
this section as you can.
■ Program DISA to require the caller to enter a system password before the
system will allow the caller access. See ‘‘Administration / maintenance
access’’ on page 4-4 and ‘‘General security measures’’ on page 4-8 for
secure password guidelines.
■ Use the system’s toll restriction capabilities to restrict the long distance
calling ability of DISA users as much as possible, consistent with the needs
of your business.
■ Block out-of-hours calling by turning off Remote Access features at an
intercom 10 administration telephone whenever possible.
■ Protect your DISA telephone number and password. Only give them to
people who need them, and impress upon these people the need to keep
the telephone number and password secret.
■ Monitor your SMDR records and/or your Call Accounting System reports
regularly for signs of irregular calls. Review these records and reports for
the following symptoms of abuse:
— Short holding times on one trunk group
— Calls to international locations not normal for your business
— Calls to suspicious destinations
— High numbers of “ineffective call attempts” indicating attempts at
entering invalid barrier codes
— Numerous calls to the same number
— Undefined account codes