VSPD.net 

Network Virtual Serial Ports Driver is an advanced utility, the purpose of which is to emulate null-modem cable on computers located in a TCP/IP LAN or connected to the Internet by creating any number of pure virtual serial ports in your system.
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Serial Splitter 

Use Serial Splitter to split serial ports at one side into multiple virtual and real serial ports at the other one, as well as join multiple serial ports into one. The unique feature of this version is many-to-many ports splitting/redirection.
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Virtual Serial Port Driver XP4.5 

Virtual Serial Port Driver XP (VSPD XP) is a powerful solution for serial port emulation. It creates virtual com ports in your system and connects them via reliable virtual link, which emulates real null-modem cable.
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VSPD Mobile Phone Edition 

VSPD Mobile can create up to 20 pure virtual serial ports in your mobile system, resulting in 10 virtual serial ports pairs available for integration. Both ports in a pair are connected via a virtual null-modem and fully emulate real serial ports.
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