Black Box 32144, Руководство пользователя

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MODEM 32144
With either type of APP, each
incoming call is password-
protected, yet there is no need for
user to enter a password. Passwords
are preprogrammed, sent over the
modems’ auxiliary channel, and
automatically compared by the
modem. 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 modem to
accept calls from modems that have
not been programmed to send the
correct password—including
modems that do not support the
modem security handshake.
The automatically invoked
password (and callback number, if
used) is established or changed.
If desired, the password can be
disabled. This allows the modem to
accept calls from modems that have
not been programmed to send the
correct password—including
modems that do not support the
modem security handshake.
The automatically invoked
password (and callback phone
number, if used) is stored in
nonvolatile memory, so it will be
maintained if the unit loses power
or upon a 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
modem will not fall back to
speeds lower than 7200 bps.
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 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 alternately.)
The APP process is summarized
below. Answer modem refers to the
local modem; originating modem
refers to a remote modem; when it
calls or attempts to call the answer
modem.
• An originating modem calls the
answer modem.
• The originating modem
automatically sends the
preprogrammed password via
the security handshake.
• If the answer modem 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: