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For countries other than Australia, DES encryption is only available to end users
who meet the security requirements of the Australian Department of Defence.
Contact your modem supplier for details of making application for a DES
equipped modem to be supplied to you.
DES Multikey
DES Multikey allows the answering modem to establish which primary keys the originating
modem is using and then automatically switch to that key.
• The originating modem uses AT*K to select the current Key and Initial Value. The modem
encrypts the current Initial Value with the current Key and transmits it just before
connection occurs.
• The answering modem then decrypts the 8 bytes received with each of its stored keys to see
if any transform into the Initial Value for that key. If none match, the answering modem
switches to that Key. MultiKey uses the Initial Value essentially as a password to allow the
keys to be matched. Security is not compromised in any way since both the Key and the
Initial Value are secret and no information can be extracted from the transmitted message.
Up to 10 keys can be specified via the AT#S Security Menu. A key of all zeros is ignored unless
it is selected as the current key with the *K command. The factory default is AT*K0 with Key
0 having an all zero Key and Initial Value.
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This should not be used as a live key, both Key and Initial Value should be set up
before use.
This mechanism can be used to allow gradual key changes throughout a network since it allows
both old and new keys to be recognised until the key change is complete. It also allows some
users temporary access with a limited time key or to control access by giving different user
groups different keys.

SuperSecure Advanced Security Mode

SuperSecure mode allows you to :
❑Have an individual password and an individual DES KEY.
❑Automatically change the DES key in a random manner after each connection without the
keys ever being knowable.
❑Have a different password on the answering modem to the originating modem.
❑Timed expiry of passwords.
With these new features, a link between two modems will be very secure. No other modem can
dial either modem and connect because the third party will not know the keys of the other users,
even if both passwords are known.