Replace serial (RS232, RS485) cables with ethernet network, using UDP - Windows Shareware $29.95. The Haxxio UDP Serial Port Redirector is the missing link between devices that speak UDP on your network and are thus "connected" to your PC, via an Ethernet port (specifically UDP over IP) and Windows applications on the PC that can only talk to a serial port. Most applications for the Redirector are based on one of (a) Replacing a simple serial connection, either RS232 or RS485, with a network connection, thus simplifying the connection and removing the cable length barrier, up to the point of crossing the planet.

(b) Requiring to communicate RS232 over a wireless connection between either PCs, or PCs and terminal servers - Wireless ethernet is much cheaper and more available than wireless RS232. Examples (c) Enabling a group of PCs and/or other devices to all communicate with each other. This can be arranged by having all the devices broadcast their messages, and by using the UDP Redirector on on one or more PCs, these PCs can also be part of this communicating group.