The VPortPro Client is a software program designed to convert serial (RS232) data to the TCP/IP packets format and TCP/IP packets to serial data. While running on your PC, VPortPro Client can receive serial data from a serial port of your PC and then send them out to a TCP/IP network through a TCP/IP socket connection on your PC. VPortPro Client can also receive serial data from a TCP/IP network through a TCP/IP socket connection on your PC and send them to a serial port on your PC.
VPortPro Client supports two transport data stream protocols:
- Raw TCP
- Telnet (with the features provided by the COM Port Control protocol specified by IETF RFC-2217)

VPortPro Client functions as a TCP/IP client (for both the protocols), i.e. it will initiate and establish connection with remote systems (by sending connection requests), and then communicate with connected TCP/IP servers. As a TCP/IP client, VPortPro Client allows to establish connection to a single TCP/IP server for each serial port. Normally any data received through the TCP/IP port that it connects to will be transmitted out the serial port and any data received through the serial port will be sent back to the TCP/IP server. This enables fully bi-directional communications. So, VPortPro Client redirects COM port to a TCP/IP port and vice versa.

Also with VPortPro Client, you can create "virtual serial ports". A virtual serial port (VSP) appears to application software as a "standard" MS Window's communications port (virtually identical to an RS-232 port). Data may be written to VSP by applications, and data may be read from VSP as though it were a standard COM port. You can configure VPortPro Client to map TCP/IP ports onto virtual serial ports. This allows MS Windows applications to generate or consume data to and from VSP as though the data were being processed by physical hardware.