Nortel Networks P0857846 - Manual (Page 149)

136 / Using System features
Norstar-PLUS Modular ICS 2.0 System Coordinator Guide P0857846 Issue 02
Direct inward system access
Control access to your Norstar system with direct inward system
access (DISA). Access to your Norstar system from the public
telephone network should always be controlled with DISA. If your
installer or customer service representative programs the line used
for remote access to answer a call automatically and wait for a DISA
internal number, callers will hear a stuttered dial tone and must enter
a Class of Service password before they are allowed into the
system.
Class of Service
To control the level of telephone service a remote user can access,
your installer can assign a remote filter and remote package to the
line used for remote access. The remote filter restricts the numbers
that can be dialed on the line, and the remote package restricts the
use of line pools and the page feature. To change the restrictions for
the line, the user can enter their Class of Service password when the
system answers with DISA, or can dial the DISA internal number
and enter their Class of Service password.
Maintaining security
To maintain the security of your system, the following practices are
recommended:
• Warn anyone to whom you give the remote access number, to
keep it confidential.
• Change Class of Service passwords often.
• Warn anyone to whom you give a Class of Service password, to
remember it and not to write it down.
• Remove the Class of Service password of anyone who leaves
your company.
Accessing Norstar remotely over the public network
• Dial the Norstar system’s remote access number.
• When you hear a stuttered dial tone, enter your COS password.
• Wait for the system dial tone.
To use the system remotely, you must use a telephone with tone
dialing to call the system.