[TUHS] Attempting To Build NOSC and BBN UNIXs + ARPANET code

[Lars Brinkhoff]

TUHS Disclaimer: I will claim this is primarily about getting Unix onto
the Arpanet, but it does also contain trace amounts of off-topic
information.  Reader discretion is adviced.

Michael Casadevall wrote:
> I do need to do a readthrough for the VDH driver, which says its for
> "very distant hosts".  I think that might be for the radio links

The hardware interfaces between a host and an IMP came in three flavors:
local host, distant host, and very distant host.  The first two are more
or less directly connected and I forget what the difference is.  But a
very distant host is basically connected over a phone line with a modem
at each end, so it's a different beast.  The VHD driver would be for
this, whilst IMP11A and ACC are local or distant.

> Hawaii

Side note: apparently tapes from the unique Hawaii BCC 500 have been
saved.  So maybe that's one more possible re-Arpanet host.

> Yup, that's what I figured. I've been trying to evaluate how much
> survives

Here's my take:
https://gunkies.org/wiki/Network_Control_Program_(ARPANET)#Implementations

So there are like four PDP-10 systems and two PDP-11.  The ELF system
will be a major challenge, RATS haven't been scanned off the printer
listing, and the BCC 500... oh boy, let's not go there now.

> I don't know if a runnable build of TENEX has been archived,

I think so.  I "almost" got one running but there was some problem...

> or if ARPA stuff for TOPS-10/20 survived.

TOPS-20AN seems to be there.  TOPS-10, nothing so far.

> I also want to look into System/360 and 370, but I get the sense none
> of the mainframe stuff survived.

I asked around; found nothing.  CDC, same.

> The other problem is of the surviving stacks, they all seem to be for
> the later 96-bit leader, I'm not certain if any of the IMP software
> that has been archived is new enough to work with that.

Nothing for the 316/516 IMP, as far as I know.  Pluribus IMP emulator,
anyone?