The additional parameters are located in the network settings for the COM port.
WEBconfig: LCOS menu tree / Setup / COM ports / COM-port server / Network settings
- Assume binary mode
Some network devices connected to a serial COM port transmit data structures
which may be interpreted as control characters (CR/LF – carriage return
/ line feed). In the default setting, the COM-ports in LANCOM devices
process this information to control the data flow. "Binary mode" instructs
a COM port to forward the data in binary format and ignore any control
characters.
Possible values:
- Yes, No.
- No.
- Newline conversion
Here you select the character to be output by the serial port when binary
mode is activated.
This setting is independent of the application communicating via the
serial port. If the port is connected to another LANCOM device, you
can either enter CRLF here or just CR. This is because the outband interface
of these devices expects a "carriage return" for the automatic determination
of data-transfer speed. However, some Unix applications interpret CRLF
as a prohibited double line feed character. In these cases enter either
CR or LF.
Possible values:
- CRLF, CR, LF
- CRLF
Note: This setting is only relevant if binary mode is deactivated for this port. - TCP keepalive
The RFC 1122 sets down a method of checking the availability of TCP
connections, called TCP keepalive. An inactive transmitter queries the
receive status from the remote station. If the TCP session to the remote
site is available, then the remote responds with its receive status.
If the TCP session to the remote site is not available, then the query
is repeated for as long as it takes for the remote to respond with its
receive status (after which a longer interval comes into play). As long
as the basic connection functions, but the TCP session to the remote
station is not available, then the remote station sends an RST packet
which triggers the establishment of the TCP session by the requesting
application.
Possible values:
- Inactive: TCP keepalive is not used.
- Active: TCP keepalive is active; only RST packets cause the disconnection of TCP sessions.
- Proactive: TCP keepalive is active, but the request for the receive status from the remote site is only repeated for the number of times defined under "TCP retry count". If this number of requests expires without a response with the receive status, then the TCP sessions is classified as "not available" and the application is informed. If an RST packet is received during the wait time, the TCP session will be disconnected prematurely.
- Inactive
Note: The setting "active" is recommended for server applications. - TCP keepalive interval
This value defines the interval between sending requests for receive
status if the first request is not affirmed. The associated timeout is
defined as being interval/3 (max. 75 sec.).
Possible values:
- Maximum 10 characters
- 0
- 0 activates the RFC 1122 default values (interval 7200 seconds, timeout 75 seconds).
- TCP retransmit timeout
Maximum time for the retransmission timeout. This timeout defines the
the interval between checking TCP-connection status and reporting the
result to the application using the TCP connection.
Possible values:
- 0 to 99 seconds.
- 0 activates the RFC 1122 default value (60 seconds).
- 0
Note: The maximum duration of the TCP-connection check is the product of TCP-retransmit-count and TCP-retry-count. The TCP application is only informed after the timeout for all attempts has expired. With the default values of 60 seconds timeout and max. 5 attempts, it can take up to 300 seconds before the application is informed about an inactive TCP connection. - TCP retry count
The maximum number of attempts for checking TCP-connection status and
reporting the result to the application using the TCP connection.
Possible values:
- 0 to 9
- 0 activates the RFC 1122 default value (5 attempts).
- 0
Note: The maximum duration of the TCP-connection check is the product of TCP-retransmit-count and TCP-retry-count. The TCP application is only informed after the timeout for all attempts has expired. With the default values of 60 seconds timeout and max. 5 attempts, it can take up to 300 seconds before the application is informed about an inactive TCP connection.