Network Serial Port Kit 

Network Serial Port Kit allows you to connect any serial port devices over TCP/IP network or Internet. Program creates and connects up to 254 virtual serial ports at a time. Physical COM ports can be connected over the network as well.
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Advanced Virtual COM Port 

This is the first software of its kind which includes both local and network virtual COM port functions. It can share your real COM ports or create virtual COM ports and connect them with a virtual null-modem cable locally or through the network.
virtual serial port share com network driver tcp/ip lan internet