User Manual
Your TrustWorthy Industrial IoT Partner
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room or a cloud application need to open a remote connection before they can transfer the serial data. If a large number of serial
devices are connected to the same network, the connection will require many resources in the control room or cloud application. To
handle these large numbers of remote connections properly, serial device servers should support flexible connection control. The
best way to do this is to open a connection only when serial data is received from a device. When the transmission is completed, the
serial device server should immediately close the connection. Without support for flexible connection control, you would need to
spend extra time handling connections at the central site or cloud application.
TCP transient connection is used primarily to save server resources. Fig.52 shows an example of configuration setting for transient
connection in TCP Client working mode under the socket page.
Fig. 52
Transient connection
4.3.
UDP Server
4.3.1. Properties
User Datagram Protocol (UDP) is a faster and more efficient transport protocol than TCP but it is a connectionless transport protocol,
it does not guarantee the delivery of network datagram. In UDP mode, you can unicast or multicast data from the serial device to one
or multiple host computers, and the serial device can also receive data from one or multiple host computers. Please beware that even
though UDP provides better efficiency in terms of response time and resource usage, it does not guarantee data delivery. It is
recommended to utilize UDP only with cyclic polling protocols where each request is repeated and independent, such as Modbus
Protocol.
When the working mode of the device is UDP server, the remote device must also work in UDP mode. You only need to specify the
Local Port that USR-N5X0 should listen to. In UDP server mode, serial port data is always sent to the last peer UDP device(IP and port)
that communicates with the USR-N5X0, and the USR-N5X0 can record the IP and port number only after the peer UDP device sends
data to the USR-N5X0 first.
Fig.53 shows an example of configuration setting for UDP Server mode under the Port1 socket page. You can configure other serial
ports in the same way.
