ZyXEL Communications Omni 56K II User Manual

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Omni 56K II and Omni 56K Plus II User’s Guide 
3-10 
 
 
 
 
 
 
 
       Specifications and Functions 
TYPE  
BIT (ON) 
RING SEQUENCE 
0.4s on, 0.2s off, 0.4s on, 0.2s off, 0.8s on; 4s off 
0.3s on, 0.2s off, 1s on, 0.2s off, 0.3s on; 4s off 
3.16 Security Function 
The Omni 56K II and Omni 56K Plus II modems provide a security function, which (when enabled) prevents 
an unauthorized user from making a connection. Two types of security function are provided. Type 1 security 
is used when the remote modem is also a ZyXEL modem; type 2 security is used when the remote modem is 
any other brand of modem. 
With the type 1 connection, the dial-in (remote) modem will send in its supervisor password for checking at 
the initial connection handshake, and the local modem will check this password against its pre-stored 
acceptable password list. With a type 2 connection, the remote terminal will be prompted to enter the 
password at the initial connection and the local modem will do the password checking. 
Two levels of security are provided. With level 1 security, the local modem will maintain the connection if 
the password check is OK, otherwise the line will be disconnected. With level 2 security, the local modem 
disconnects the line if the password has been found in its pre-stored acceptable list and then dials back to the 
phone number corresponding to the dial-in password. The line is simply disconnected if the password does 
not march. 
4 user passwords may be defined. The corresponding 4 dial-back numbers are the modem's 4 stored phone 
numbers. Any character (ASCII 0-127) can be used in the password field and the maximum password length 
is 8 characters. 
The security functions are only accessible through AT commands in terminal mode. Any access attempt will 
result in the modem's prompting to enter the supervisor password. The attempt will be rejected if the entered 
password is not correct. The default supervisor password is ZyXEL when the modem is shipped from the 
factory. This supervisor password is also the password sent for automatic password checking in a type 1 
connection. To modify the supervisor password, use 
AT*HS 
You will be asked for the original password and a new password, and then to re-enter the new password for 
verification. For example: 
PASSWORD (Enter supervisor password) 
******** 
PASSWORD (Enter new supervisor password) 
********