User`s manual

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command string as the “K” command. The password that is set remains in effect until
another “K” command is received from the same remote address.
It would be used to establish a password for a remote address, to be used for such things
as locking and unlocking outputs and modifying the router configuration. When the router
receives a protected command (one which requires use of a password) from a remote
address, it compares the current password for that remote address with the password
required to execute the protected command. Protected commands consist of many of the
“G” commands that change router configuration, as well as take and salvo trigger
commands when the output to be taken is locked. In the former case, the administrator
password is the one that must be sent in the “K” command to permit the router
configuration to be changed, while in the latter case the password that was used to lock
the output is the one that must be sent in the “K” command to permit the take to occur.
Refer to the “B” command and the “G ADMIN_PASSWORD” command (in a separate
document) for more information.
For example, the command:
** M197 K1777 !!
requests that password 1777 be stored as the current password for remote address 197.
The command:
** M197 Y7,9 !!
requests that output 7 be connected to input 9, using the password stored for remote
address 197 as the output lockout override password. The take will succeed if output 9 is
either not locked or is locked with password 1777. Otherwise, the take will fail.
“M”: Set Remote Address
The command "M" is followed by a remote address value, and it sets the remote address
to be used by all remaining commands in the current command string. This command is
supported on larger routers. It would be used when a client/server software system on a
router control port permits multiple remote users to send commands to the router through
that control port. In such a system, the server software that talks to the control port can
insert an “M” command at the beginning of each command string it sends to the router on
behalf of its clients. The server would assign a different address to each of its clients. The
router uses the address to control access to and modification of protected resources. The
“M” command will typically work in conjunction with the “K” command, which allows a
password to be sent to the router. Some commands, such as those that allow
modification of router configuration settings, might require entry of an administrator
password before allowing the router configuration to be modified. The “K” command is
used to send the password, but the router must be able to record that password in
association with a particular remote user. The router would save the password as the one
established by the remote address specified in the “M” command. The examples below
show how this would work.
If the “M” command is not present in a control string received on a serial port, the address
assigned to the serial port itself is used as the address for all commands in that
command string.
The “M” command works on an honor system. There is nothing to keep a remote device
from forging a false address. This conforms with the philosophy of providing protection
mechanisms that are not designed to be totally hack-proof, but rather, are designed
under the assumption that controlling devices will honor the system. A dedicated hacker
can always hack into the system if he chooses. Note, however, that the server in a
client/server relationship can provide a great deal of added security for the system,