Cabletron Systems Netlink FRX4000, Руководство пользователя

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Configuring Async Ports 12-13
RTS-CTS H/W Flow Control
enables hardware flow control through stop/start of data using RTS (pin 4), CTS (pin
5), and CD (pin 8) on the RS-232 interface. Flow control is usually necessary to
maintain communication without data loss between devices or channels with different
throughput capabilities.
RTS-CTS flow control works only on a physical DTE port, as physical DCE ports
have RTS looped back internally to CTS.
The other common method of flow control is XON-XOFF (parameters 5 and 12 of the
async PAD profile); however, when the data itself is likely to contain these characters
(for example, in a binary file), XON-XOFF may become inadequate.
Disconnect Timer
is an inactivity timer that determines the length of time the port can go without trans-
mitting or receiving characters, as determined by the parameters
Timeout if No Login
,
Timeout if No Call
, and
Timeout if No Data
. (The actual timeout may be up to thirty
seconds after the number of minutes specified.)
Disconnect Duration
is the length of time the PAD will drop the modem signals after logout of the user
(whether caused by a timeout or user command). For a dial-in line, this should be set
to something greater than
0
, to ensure that the line does not remain physically con-
nected after a timeout or logout. For a leased or directly connected line,
Disconnect
Duration
should be
0
, to avoid disconnections.
Timeout if No Login
if
Y
, starts the disconnect timer the moment the user enters login state; e.g., when DSR
is asserted on the modem, or when a direct-connect user logs out. As long as the dis-
connect timer has not expired, the user can continue to attempt to log in. On a dial-in
line, if the timer has expired and
Disconnect Duration
is not
0
, a physical disconnect
will be initiated. (The modem signals will be dropped.)
If the user logs out, the
Disconnect Timer
will be ignored, and the line will immediately
be disconnected.
This parameter should be
N
for a leased line; otherwise, the PAD banner and prompt
will periodically be output. (This is harmless, but unnecessary.)
This parameter is automatically disabled on a PVC connection.
Timeout if No Call
if set to
Y
, starts the disconnect timer as soon as the user logs in or a virtual circuit is
cleared, and the PAD is ready to receive commands from the user. The timer is reset
every time the port receives or transmits a call.
This parameter is automatically disabled on a PVC connection.
Timeout if No Data
if set to
Y
, starts the disconnect timer as soon as a virtual circuit is connected. The timer
is reset every time the port receives or transmits a character. If
Y
is specified and the
user has escaped from the data transfer state (by pressing
[Ctrl] [P]
), any data sent to
the port will not be output through the port.
When the disconnect timer expires, the software will check for any data waiting to be
output, as well as the state of the user. If there is data waiting and the user has escaped