Moxa Technologies NPort 5400 - Manual (Page 24)

NPort 5400 Series User’s Manual Choosing the Proper Operation Mode
4-4
TCP Client Mode
In TCP Client mode, NPort can actively establish a
TCP connection to a pre-defined host computer
when serial data arrives.
After the data has been transferred, NPort can
automatically disconnect from the host computer by
using the TCP alive check time or Inactivity time
settings. Refer to chapter 5 for more details.
As illustrated in the figure, data transmission
proceeds as follows:
1. The NPort configured for TCP Client Mode
requests a connection from the host.
2. Once the connection is established, data can be
transmitted in both directions—from the host to
the NPort, and from the NPort to the host.
UDP Mode
Compared to TCP communication, UDP is
faster and more efficient. In UDP mode, you can
multicast data from the serial device to multiple
host computers, and the serial device can also
receive data from multiple host computers,
making this mode ideal for message display
applications.
Pair Connection Mode
Pair Connection Mode employs two NPort 5400 in tandem, and can be used to remove the
15-meter distance limitation imposed by the RS-232 interface. One NPort 5400 is connected from
its RS-232 port to the COM port of a PC or other type of computer, such as hand-held PDAs that
have a serial port, and the serial device is connected to the RS-232 port of the other NPort 5400.
The two NPort 5400 units are then connected to each other with a cross-over Ethernet cable, both
are connected to the same LAN, or in a more advanced setup, they communicate with each other
over a WAN (i.e., through one or more routers). Pair Connection Mode transparently transfers
both data and modem control signals (although it cannot transmit the DCD signal) between the
two NPorts.