Johnny Billquist wrote: Are you actually talking now about implementing a DECnet stack on a machine in user mode? That is definitely not doable. Is that really true? I don't believe it. How about an Einstein style "gedanken experiment" - put simh on a machine (which is an entirely user mode program), load VMS on it. Bingo - a user mode implementation of a DECnet stack. I don't mean this as a practical solution to DECnet on Linux, but it's clearly possible to get all the Ethernet access you need to implement DECnet in a user mode program. N.B. "user mode" is not the same as "run as root". Promiscuous mode requires root privilege, but that's still a user mode program. Bob