I’m looking for the origins of SLIP and PPP on Unix. Both seem to have been developed long
before their RFC’s appeared.
As far as I can tell, SLIP originally appeared in 3COM’s UNET for the PDP11, around 1980.
From the TUHS Unix tree, first appearance in BSD seems to be 4.3 (1986).
Not sure when PPP first appeared, but the linux man page for pppd has a credit that goes
back to Carnegie Mellon 1984. First appearance in BSD seems to be FreeBSD 5.3 (2004),
which seems improbably late (same source).
Paul