Multi-Tech Systems MT5600BA-V92 User Manual

Page of 57
Chapter 6 – Callback Security 
Multi-Tech Systems, Inc. MT5600BA-V92 User Guide 
34
            
 
Chapter 6 - Callback Security 
 
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.  
It is possible to implement password protection without callback by storing a hyphen (-) before the callback 
phone number. The caller must then append a hyphen to his password to establish the direct connection. 
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. For example, if you assign the password “APRICOT” to memory location 16 and, in a 
separate operation, also assign phone number 6127853000 to memory location 16, the modem 
calls phone number 6127853000 when it receives the password “APRICOT.”  
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 
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 callback 
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.