Serial port virtualizer

All,

I'm looking for a windows and Linux driver that will support up to 128
virtual serial ports, but use TCP/IP to communicate between 2 computers.
One box is Linux and will have a program that receives commands from
the serial ports and sends data in response. This box simulates actual
hardware.

The other box is Windows 9x/NT/2000/XP and runs the client program that
can communicate with up to 128 of these devices. It would have up to
128 virtual serial ports and connect to the simulator via TCP/IP.
Anyone know of software that does this? Couldn't find any so far.

An alternative approach is running everything on the Windows box (and
adding a monitor to see both programs running). There are serial port
virtualization programs for Windows, with a cost of $100 to about $250.
I thought there was a freeware project to do this, but I can't find it
either. Anyone know if it exists any longer?

Thanks for any helpful on-topic information.

Dave,

There are serial port virtualization programs for Windows, with a cost ...

The best serial port virtualizer is/was SIO for OS/2; http://www.gwinn.com/