> 
> Even better (in terms of work to invest): Teach simh (does it simulate
> the network interface in software?) use /dev/tun and connect the
> hosting OS to tun0. But I guess this won't work because simh wants to
> talk to layer 2 .
> 
That should be easy to fix. There are "prior art" in terms of using /dev/tun
and DEQNA; the P11 PDP11 emulator uses /dev/tun for network communications.

-- Ragge