Chapter 5 – Callback Security
Multi-Tech Systems, Inc. MT5634IND User Guide (S000369B)
16
Setting Callback Security Message Parity
The 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 PhoneTools
.
2.
In the terminal window, type
AT#S
xxxxxxxx
, 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 PhoneTools.
2.
In the terminal window, type
AT#S
xxxxxxxx
, 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.
7.
To store a callback phone number in the first memory location, type
AT&Z0=
[
+
][
-
]
AT
xxxxxxxx
[
,
???
], where
xxxxxxxx
is the dialing string. Press
Enter
. The phone number must be preceded by
DT
for tone dialing or
DP
for pulse dialing. The dialing string can also include other AT commands. Example:
AT&Z0=+-
ATM0DT5551212
. Up to 35 characters can be used. The +,
-,
and
???
characters are optional:
+
Number entry. Enables a mobile caller to enter his current phone number for callback.
-
Direct connection. Enables a caller to choose direct connection without being called back.
,???
Extension entry. Must be used with the
+
command. Enables a caller to enter an extension number
for callback. The number of
?
characters must equal the number of digits in the extension.
8.
To store a callback phone number in the second memory location, type
AT&Z1=
[
+
][
-
]
AT
xxxxxxxx
[
,
???
],
where
xxxxxxxx
is the dialing string, and press
Enter
. Note that the memory location number in the
command is incremented by one.
9.
Repeat, through memory location 29, until all dialing strings are entered.
10.
To review your entries, type
AT&V
and press
Enter
.
Calling Procedures
Use the following procedures to call a modem that has callback security enabled. Note that Autoanswer must be
enabled on the calling modem (
S0=1
).
Password-Only Callback
Use this procedure when calling from a fixed location.
1.
Using a data communications program such as PhoneTools, dial the number of the callback modem.
2.
When the connection is established, the callback modem responds with the following message:
Password>
3.
Type the password corresponding to the phone number for your modem. Press
Enter
.
You have
three attempts or one minute to enter a valid password.
4.
If the password is valid, the following message appears, and the modems disconnect:
OK Disconnecting
5.
After the delay specified by the
#CBD
n
command, the callback modem calls the number associated
with the password. If the callback modem is unable to establish a connection, it tries again, up to the
number of attempts specified by the
#CBA
n
command.
6.
After the modems reconnect, the following message reappears:
Password>
7.
Type the same password that you used to initiate the call. You are allowed three attempts to enter the
password, after which you will be disconnected.
8.
If the password is valid, the following message appears and the modems establish a working
connection:
OK Connecting
