Seems to allow communication to 2 or 4 (based on model) serial ports through ethernet. They have 'drivers' for unix in the form of C source code.

Devices connecting serial ports (typicaly 8-16, but there are 128 port models) to various hosts via Ethernet (or other LANs), usually called terminal servers or communication servers are around for more than a decade (and now their main use is as Internet dial-up access points). Their software is optimised for use with telnet, SLIP and PPP protocols initiated 'from the serial side'. However, there is usually a feeture where a certain TCP port at device's address corresponds directly to particular serial port, i.e. whatever we sent to TCP port gets output through serial and vice versa, making it almost trivial to 'serial enable' whatever application one writes on Unix. Also, from there to virtual serial devices on Unix box is relatively short way.

Do you know how much does EDAS unit cost (full-fledged comm servers are not cheap)?

Dragi "Bonzi" Raos
Zagreb, Croatia
Q#5196, MkII#80000376, 18GB green