WHAT IS SERIAL PORT SERVER?
A serial port server (also a serial server or port redirector) is a device that relays data between a computer serial port and an Ethernet LAN. As a result Ethernet can be used instead of serial cables, thus serial devices can be placed anywhere, not necessarily by the computer with which they are used.
Serial port server purpose:
The purpose of port redirector is to make virtual COM port work as close as possible to real COM port.
Applications usually use serial port server through one or more virtual serial ports, that the server creates (configured by its user). When the application opens the virtual serial port, the port redirector makes an IP network connection to the device server at the specified IP address and TCP port number that corresponds with the remote device on the server. Then port redirector starts transmitting the application data between the virtual serial port and the device server.