Multi-Tech Systems MT5600BL - Manual (Page 70)

MultiModemII User Guide
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Introduction
This chapter describes how to use callback security with your modem.
Callback security protects your network from unauthorized access and helps control
long distance costs. When callback security is enabled, all callers are requested to
enter a password. If the password is invalid, the caller can try twice more before the
modem hangs up. If the password is valid, the modem hangs up and returns the call
by dialing the phone number associated with the password.
The modem can store up to 30 callback phone numbers and 30 callback passwords.
Phone numbers can be up to 30 characters long and can contain the pause (,) and
wait (W) characters in addition to the digits and characters normally found on a
touch-tone keypad. Passwords can be up to 10 characters long.
Callback phone numbers are associated with callback passwords by being assigned
to the same callback memory location. Thus, if you assign the password “APRICOT”
to memory location 16 and, in a separate operation, also assign phone number
6127853000 to memory location 16, when the modem receives the password
“APRICOT,” it calls phone number 6127853000.
Because there is no way to examine the passwords and phone numbers stored in the
modem, it is important to write them down as you enter them. A form that you can
print out for this purpose is provided on the last page of this chapter.
Setup Procedures
Turning Callback Security On and Off
Note: Autoanswer must be enabled (S0=1 or S0=2) for callback security to work.
AT Command Method
1. Open a terminal program, such as HyperTerminal.
2. In the terminal window, type one of the following commands:
• To turn on callback security, type AT#DB1 and press E
NTER
. With remote call-
back security turned on, each caller is asked to enter a password, then is
disconnected and called back by the modem. Also, dialing number locations
0–3, for use with the DS=y dialing command, are replaced by callback dialing
number locations 1–30.
• To turn off callback security, type AT#DB0 and press E NTER . Callers no longer
need a password to connect to the modem, the modem is unable to call them
back, and stored dialing number locations 0–3 become available.