I have two computers with USB ports.
I wish them to communicate as simply as mid-20th-century computers did.
Then we used RS232-C with a null modem &/or appropriate software
software at both ends.
The underlying problem is that both ends egotistically expect to be
*MASTER*.
The hardware problem is solvable [e.g.
http://www.ftdichip.com/Products/Cables/USBtoUSB.htm].
The software is another case :<
The best Linux specific link I've found is dated September 2005
[http://www.linux-usb.org/usbnet/]
I've done DuckDuckGo searches for permutations/combinations of
usb, "peer to peer", lan, and bridge.
Most is Windows/Mac centric.
There were hints that needed drivers may exist in current Linux core.
Pointers to good references and/or better search terms?
TIA