Telenetics 56 Network Card User Manual


 
AT Commands
Page 41
Encryption
Your modem supports Data Encryption Standard (DES) encryption. DES encryption allows
you to encrypt data being passed to a remote modem. The remote modem must support Cipher
Feedback (or CFB) DES encryption in order to decrypt the data sent from your modem.
The #E1 command is used to enable DES encryption.
The modem requires you to enter an encryption Key and an Initial Value.
These are two 16-character hexadecimal numbers. Both the Key and Initial Value are specified
by the user, making the encrypted data virtually impossible to decrypt without access to the
Key and Initial Value.
Both modems must have DES encryption and error correction selected and must use the same
encryption Key and the same Initial Value.
Only use a reliable error correction mode when using DES encryption. This will
ensure you will only establish encrypted connections.
The modem can store up to 10 DES Key/IV pairs. Use AT*K to select the Key you wish to use.
For example AT*K5 tells the modem to use the key and IV from register 5.
To enter the DES Key and Initial Value:
Type: AT#S <E>
Type: 9 <E>
You will be prompted with the following message:
Select DES Key register (0-9) (Key ENTER/or main menu):
You should select one of the 10 available registers to store the new Key.
The modem will respond:
Enter New DES Key:................
Re-enter DES Key:................
Enter new DES IV:................
Re-enter DES IV:................
Enter the Key and Initial Value as a 16-character hexadecimal number <E>
You will be prompted to re-enter the Key and Initial Value, to verify the correct Key and Initial
Value has been entered. You may then enter a new DES Key into another register or press
ENTER to return to the main menu.
To enable DES encryption, issue the AT#E1 command. The next time your modem establishes a
connection with another modem, it will encrypt outgoing data and attempt to decrypt incoming
data.