User guide

Chapter 5 – Callback Security
20 Multi-Tech Systems, Inc. MT9234ZBA-Series User Guide
3. Type one of the following commands:
● To turn off callback security: Type AT#CBS0 and press Enter. Callers no longer need a password to
connect to the modem, the modem is unable to call them back, and the stored dialing command
locations 0–3 become available.
● To turn on both local and remote callback security: Type AT#CBS1. Press Enter. With local security
turned on, you must enter the setup password before you can enter any AT command except the AT,
ATIn, and AT#Sxxxxxxxx commands. For a description of remote callback security, see the following
paragraph.
● To turn on remote callback security only: Type AT#CBS2 and press Enter. With remote callback security
turned on, each caller is asked to enter a password, is called back, and then is asked to enter the
password again before a connection can be made. Also, dialing command locations 0–3 for use with the
DS=y dialing command are replaced by callback dialing command locations 0–29.
● To temporarily disable callback security if the modem is set to #CBS1 or #CBS2 (for instance, to call
another modem): Type AT#CBS3 and press Enter. The modem returns to its original setting when you
issue the hangup command (+++ATH) or the modem is reset. Note that if a remote modem breaks the
connection, callback security remains disabled.
Setting Callback Security Message Parity
The modem’s password prompt and messages parity must match the parity of the computer to which the
modem is connected.
1. Open a data communications program such as HyperTerminal.
2. In the terminal window, type AT#Sxxxxxxxx, where xxxxxxxx is your password. Press Enter. The modem
responds with OK if the setup password is correct and ERROR if it is wrong.
3. The modem’s parity default value is No parity (AT#CBP0). To change the modem’s default to use even
parity, type AT#CBP2. Press Enter. For odd parity, type AT#CBP1. Press Enter.
4. To store the new parity value, type AT&W. Press Enter.
Assigning Callback Passwords and Phone Numbers
1. Open a data communications program such as HyperTerminal.
2. In the terminal window, type AT#Sxxxxxxxx, where xxxxxxxx is your password. Press Enter. The modem
responds with OK if the setup password is correct and ERROR if it is wrong.
3. Enable callback security by typing AT#CBS1 or AT#CBS2 and pressing Enter.
4. To store a callback password for the first callback memory location, type AT#CBN0=xxxxxxxx, where
xxxxxxxx is the first password. Press Enter. The password must be unique, must be six to eight characters in
length, and must not contain a + or - character.
5. To store a callback password for the second callback memory location, type AT#CBN1=xxxxxxxx, where
xxxxxxxx is the second password. Press Enter. Note that the memory location number in the command is
incremented by one.
6. Repeat as many times as necessary, up to memory location 29, until all passwords are entered.