Specifications

Operat ion
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Note that in the case of an unintelligent loopback mechanism, such as
a simple turn-around connector, the function code will not change.
4.3.2 Loop Requester
A receipt number is chosen and the state of the operation is set to
"not complete". The input data provided
is transmitted to the
destination system as a Loop Data message. If the transmit
is not
accepted, the error code is returned and the receipt number marked
complete. If the transmit succeeded, a receive
is posted. Note that
it may be necessary to post the receive first to avoid a race between
the posting of the receive and the receipt of the message.
When the transmit and receive are both complete, if they were
successful the received data
is compared to the transmitted data. If
they do not match or the receive or transmit failed, the appropriate
error is recorded. Otherwise, success and the responding systeir.
address are recorded.
The Loop-poll function returns the state
of the operation.
4.4 Remote Console
This section describes the operation of the Remote Console Server and
Requester. For this section, the term "target system" means the
system whose remote console is being used (i.e. the one running the
Console Server). The term "command system" means the system sending
the commands
(i.e. the one running the Console Requester).
The console carrier protocol is a half-duplex polled protocol. That
is, the Console Requester must poll the remote Console Server for
information.
4.4.1 Console Server
The Console Server operates within the following state diagram: