SENA STS Series User Manual
Page 45
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User Authentication
In TCP mode, STS Series support user authentication for port access. If this option is enabled, user
should enter the user ID and password before accessing the port. (For user administration, please
refer to the section 6.6. User Administration)
Telnet protocol
In TCP mode, STS Series support Telnet Com Port Control Option (RFC2217 compliant) so that user
can control serial parameters like baud rate, data bits and flow control option using his local RFC2217-
compliant Telnet client program. (Please refer to section 4.2.9 Serial Port Parameters for more detail
information about serial parameters)
Usually this option is used with the RFC2217-compliant COM port redirector so that user can control
parameters of serial ports of STS Series using his serial port application program.
For this purpose, SENA OEM version of Serial/IP from Tactical Software, LLC is bundled with STS
Series. Please refer to documentations of Serial/IP for more detail information about using the COM
port redirector. (Please refer to section Appendix 6. Using STS Series With Serial/IP for more detail
information)
Max. allowed connection
The STS Series supports multiple connections from external host(s) to a serial port up to 32. But if
there are remote host connections by the remote host list configuration already, possible number of
connection is reduced to (Max. allowed connection - remote host(s) connected already). For example,
if user set Max. allowed connection as 32 and if there are 3 connections from STS Series to remote
hosts, which are configured in the remote host list, then maximum number of connection from external
hosts to a serial port will be reduced to 29 (=32 – 3). For more detail information for remote host list
configuration, please refer to 4.2.5 Remote Host Configuration section.
Cyclic Connection
If Cyclic Connection function is enabled, the STS Series will make an attempt to connect to the user-
defined remote host(s) at a given interval even if there’s no incoming serial data from the device
connected to that serial port. If there is data on the remote host(s) to be sent to serial device, it can be
transferred to the serial device via STS Series’s serial port after the connection is established.
Eventually, users can monitor the serial device periodically by making the remote host send the serial
command to the STS Series whenever it is connected to the remote host. This option is useful when
users need to gather the device information periodically even if the serial device does not send its data
periodically. Figure 4-6 shows the State Transition Diagram of the session operations in TCP mode.