Raymar Alliance V.32, Инструкция по эксплуатации

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0049-2702-XXX Alliance Series Modems – USER MANUAL 08/05/2010
Rev. A Page 86 of 197
With either type of APP, each incoming call is password protected, yet there is no need for users
to enter a password. Passwords are preprogrammed, sent over the modem’s auxiliary channel,
and automatically compared by the ALX. The only time manual intervention is required is when
the password (and callback number, if used) is established or changed.
If desired, the password can be disabled. This allows the ALX to accept calls from modems that
have not been programmed to send the correct password – including modems that do not support
the ALX security handshake.
The automatically invoked password (and callback phone number, if used) is stored in
nonvolatile memory, so it will be maintained in the event of a power loss or quick (soft) reset.
However, a factory reset will clear the automatic password (and callback number, if used)
from memory.
Note: When APP is used, the ALX will not fall back to speeds that do not use trellis coding.
After a connection has been established using the security handshake and automatic password
(and callback phone number, if used), a flashing “S” will be displayed in the top left corner of
the TIA/EIA status screen to indicate that a secure connection has been made. (If the modem is
in a dial mode, “S” – and “D” for dial line occupied – will flash alternatively.)
The APP process is summarized below.
Answer modem (or ALX) refers to the local ALX;
originating modem refers to a remote modem when it calls or attempts to call the answer modem.
•
An originating modem calls the answer modem.
•
Originating modem automatically sends the preprogrammed password via the security
handshake.
•
If the answer ALX is configured for APP without callback, it confirms the password and
connects.
For APP without callback, this is the end of the process.
For APP with callback, the process continues:
•
Both modems go on-hook.
•
Answer ALX calls the originating modem back.
•
Modems exchange security handshake (again) and connect.
Configuring Modems for APP
The procedures for configuring the originating and answer modems for both types of APP are
summarized below and then explained in detail in the subsequent sections.