On Tue, 2023-09-26 at 00:15 +0000, Dan Cross wrote:
> > I seem to remember Microsoft also used VAX machines to build
> > Windows in
> > the early days. Was that true?
>
> The early days of Windows NT are well-documented in the book,
> "Show Stopper!" by G. Pascal Zachary.  In short, they used OS/2
> and 386 machines; NT was self-hosting within a couple of years.

Yes thanks, looks like they did use PDPs for the early 8 bit stuff.
--
Tactical Nuclear Kittens

On Mon, 2023-09-25 at 13:27 -0700, gah4 wrote:
> > I seem to remember Microsoft also used VAX machines to build
> > Windows in
> > the early days. Was that true?
>
> The early days of MS were on PDP-10s. The Living Computer Museum
> has the first KS-10 that MS used.  Paul Allen really liked the PDP-
> 10,and that was the first computer Paul and Bill did much of the work
> on.
>
> I suspect that as DEC went to VAX, MS would have done that, too,
> but I don't know that one at all.
>
> I suspect that if they had a choice, it would have been PDP-10
> forever.

Yes, I misremembered for sure. Yes I think they did all their early 8
bit stuff on the PDP. Thanks.
--
Tactical Nuclear Kittens

On Sunday, September 24, 2023 at 10:10:45 AM UTC-4, John Dallman wrote:
> Gordon Bell, who was Vice-President of Engineering at DEC 1972-83 is
> still alive and documenting much of his life on the web. There's DEC
> stuff at https://gordonbell.azurewebsites.net/Digital/DECMuseum.htm
>
> Something particularly interesting is this document on DEC strategy as of
> 1979:
>
> https://gordonbell.azurewebsites.net/Digital/VAX%20Strategy%20c1979.pdf
>
> At the time, DEC's other active product ranges were PDP-8, DEC-10/DEC-20
> and PDP-11. They had decided in 1975 to create an architecture that built
> upwards from the PDP-11, rather than building lower-cost DEC-10 machines.
> The reasons for doing that were the large installed base of PDP-11s and
> the convenience of 8-bit bytes for data communications, especially with
> IBM mainframes.
>
> As of 1978/70 they had achieved this and were deciding what to do next.
> The strategy expressed in this document is to continue to sell the other
> ranges, but concentrate development efforts on the VAX family, and that's
> what basically happened. Using a single architecture is seen as a
> competitive advantage against IBM's proliferation of incompatible
> architectures, which is pretty reasonable, since IBM saw the same problem..
>
>
> Bell regards competition from "zero cost" microprocessors such as the
> 8086 and 68000 as likely more significant than other minicomputer
> companies, but fails to make a plan to deal with them. DEC was eventually
> defeated by 80386 and later PCs and RISC workstations, and that failure
> seems to start here. He assumes that DEC can dominate the market for
> terminals for its minis by using PDP-11 and VAX microprocessors, but
> doesn't seem to realise that compatible terminals can be built at much
> lower cost using third-party microprocessors. In any case, the
> replacement of minis by PCs and workstations meant that the terminal
> market basically vanished.
>
> The idea of running VMS on a terminal with a total of 64KB of RAM and ROM
> in 1982 seems implausible now, but it seems to have been the reason for
> 512-byte pages. Bell praises the extremely compact VAX instruction set
> and its elaborate function calls, without appreciating the ways they will
> come to inhibit pipelining and out-of-order execution, and thus doom the
> architecture to uncompetitive performance.
>
> John

For people needing more information on this topic, purchase a copy of "DEC Is Dead, Long Live DEC" (2003-2004) by Edgar H. Schein. Appendix E was written by Gordon Bell. The book was commissioned by Ken Olson as a post-mortem warning to other American companies.

https://neilrieck.net/docs/recommended_books_technology.html#dec

The Coles Notes version of the story centers around missed opportunities, and mistakes, by DEC as the industry shifted from CISC to RISC. Then bad advice at the top decided to bet the farm on CISC in the form of the water-cooled Aquarius (VAX-9000). A huge amount of money was also wasted when DEC decided to manufacture their own chips (Alpha) at Hudson Mass.

I work for a Canadian telecom so we spread our purchases across many companies. I still recall working on a VAX-8550 dual-host cluster (1987-1988) in Toronto when people down the hall had just purchased a 32-bit SPARC server from SUN, which was much smaller than our VAX cluster but was much faster. Over the next 15 years my employer bought a lot of SUN hardware which grew larger but was always faster. I work in Canada where there are two official languages (English + French) and it goes without saying that UNIX always did a better job supporting international character sets, at a time when many American companies refused to move beyond ASCII.

But for me, DEC's hatred for C, UNIX and TCPIP was just plain stupid since 16-bit PDP and 32-bit VAX were responsible for creating ARPAnet.
https://neilrieck.net/links/cool_computer.html#internet
Working on a VAX, once Bill Joy had rewritten all the new libraries in C, they raced from university to university.

Back in 1992, I was working on a VAX-6000 when my employer asked me to install a TCP/IP stack. We were instructed to buy the software from Process Software because DEC's product was still considered experimental. Once on TCPware, we stuck with that product on VAX and Alpha. We would have stayed with it for Itanium but since TCPware didn't support IPv6 we migrated to MultiNet.

Neil Rieck
Waterloo, Ontario, Canada.
http://neilrieck.net

In article <944e6c54-4d47-4bf8-a1c5-736f594cac9cn@googlegroups.com>,
Neil Rieck <n.rieck@bell.net> wrote:
>[snip]
>But for me, DEC's hatred for C, UNIX and TCPIP was just plain stupid since 16-bit PDP and 32-bit VAX were responsible for creating ARPAnet.
>https://neilrieck.net/links/cool_computer.html#internet
>Working on a VAX, once Bill Joy had rewritten all the new libraries in C, they raced from university to university.

This is surprising to me. My sense was always that there was
more done on the ARPANET with the PDP-10 than the -11, though
there were certainly a lot of PDP-11 hosts in the early days.
Still, I'd put the PDP-10 as more responsible for ARPANET than
the -11.

Certainly, once 4.1c BSD got TCP/IP and that escaped to
universities, Unix on VAX (and then whatever BSD was ported to;
Sun for instance got TCP/IP from Berkeley) became dominant on
the Internet.

>Back in 1992, I was working on a VAX-6000 when my employer asked me to install a TCP/IP stack. We were instructed to buy the software from
>Process Software because DEC's product was still considered experimental. Once on TCPware, we stuck with that product on VAX and Alpha. We
>would have stayed with it for Itanium but since TCPware didn't support IPv6 we migrated to MultiNet.

In some respects, I think that DEC's vision for the world was in
fact too early: highly networked, workstations, terminals and
hosts all interconnected. It was quite compelling, but just a
tad too early to pick up TCP/IP etc.

- Dan C.

Neil Rieck <n.rieck@bell.net> writes:

> But for me, DEC's hatred for C, UNIX and TCPIP was just plain stupid since
> 16-bit PDP and 32-bit VAX were responsible for creating ARPAnet.

> https://neilrieck.net/links/cool_computer.html#internet

> Working on a VAX, once Bill Joy had rewritten all the new libraries in C,
> they raced from university to university.

A great deal of the work on the ARPANET and early Internet was done on PDP-10
family computers running BBN's TENEX, DEC's TOPS-20 (a TENEX derivative),
Stanford AI Lab's WAITS (a Tops-10 derivative), and MIT AI Lab's ITS.

The 16 bit computers used as routers on the ARPANET were Honeywell products,
not DEC.

Unix(TM) did not get TCP/IP until the 1980s, a dozen years after the ARPANET
began, and several years after TCP/IP was defined. The standards were hosted
on a PDP-10 at SRI, and model implementations were generally done on PDP-10s.

--
Rich Alderson news@alderson.users.panix.com
Audendum est, et veritas investiganda; quam etiamsi non assequamur,
omnino tamen proprius, quam nunc sumus, ad eam perveniemus.
--Galen

Rich Alderson wrote:
> Neil Rieck wrote:
>> But for me, DEC's hatred for C, UNIX and TCPIP was just plain stupid
>> since 16-bit PDP and 32-bit VAX were responsible for creating
>> ARPAnet.
>
> A great deal of the work on the ARPANET and early Internet was done on
> PDP-10 family computers
>
> Unix(TM) did not get TCP/IP until the 1980s, a dozen years after the
> ARPANET began

To this I'd like to add, first there were a few PDP-11s running Unix
with the NCP protocol on the pre-TCP ARPANET. E.g. University of
Illinois and RAND. Second, VAX computers weren't even around when
ARPANET got started. In fact, were there any at all on the ARPANET
before the 1983 flag day?

In article <7w5y3wjepw.fsf@junk.nocrew.org>,
Lars Brinkhoff <lars.spam@nocrew.org> wrote:
>Rich Alderson wrote:
>> Neil Rieck wrote:
>>> But for me, DEC's hatred for C, UNIX and TCPIP was just plain stupid
>>> since 16-bit PDP and 32-bit VAX were responsible for creating
>>> ARPAnet.
>>
>> A great deal of the work on the ARPANET and early Internet was done on
>> PDP-10 family computers
>>
>> Unix(TM) did not get TCP/IP until the 1980s, a dozen years after the
>> ARPANET began
>
>To this I'd like to add, first there were a few PDP-11s running Unix
>with the NCP protocol on the pre-TCP ARPANET. E.g. University of
>Illinois and RAND. Second, VAX computers weren't even around when
>ARPANET got started. In fact, were there any at all on the ARPANET
>before the 1983 flag day?

Almost certainly. The initial TCP/IP implementation work for
Unix was being done at BBN at the time, and I imagine that meant
VAXen connected to ARPANET.

- Dan C.

On 2023-09-27 15:09, Dan Cross wrote:
> In article <7w5y3wjepw.fsf@junk.nocrew.org>,
> Lars Brinkhoff <lars.spam@nocrew.org> wrote:
>> Rich Alderson wrote:
>>> Neil Rieck wrote:
>>>> But for me, DEC's hatred for C, UNIX and TCPIP was just plain stupid
>>>> since 16-bit PDP and 32-bit VAX were responsible for creating
>>>> ARPAnet.
>>>
>>> A great deal of the work on the ARPANET and early Internet was done on
>>> PDP-10 family computers
>>>
>>> Unix(TM) did not get TCP/IP until the 1980s, a dozen years after the
>>> ARPANET began
>>
>> To this I'd like to add, first there were a few PDP-11s running Unix
>> with the NCP protocol on the pre-TCP ARPANET. E.g. University of
>> Illinois and RAND. Second, VAX computers weren't even around when
>> ARPANET got started. In fact, were there any at all on the ARPANET
>> before the 1983 flag day?
>
> Almost certainly. The initial TCP/IP implementation work for
> Unix was being done at BBN at the time, and I imagine that meant
> VAXen connected to ARPANET.

Well, before flag day, ARPANET wasn't speaking TCP/IP...

Johnny

Johnny Billquist wrote:
> Dan Cross wrote:
>>> In fact, were there any [VAXen] at all on the ARPANET before the
>>> 1983 flag day?
>> Almost certainly. The initial TCP/IP implementation work for Unix
>> was being done at BBN at the time, and I imagine that meant VAXen
>> connected to ARPANET.

I meant VAX machines talking the NCP protocol.

> Well, before flag day, ARPANET wasn't speaking TCP/IP...

Yet, there were experiments with TCP long before the flag day so it's
not a 100% either/or situation. I get the feeling (but I have no
evidence handy) some subset of nodes got started using TCP before NCP
was shut down. On several occasions in 1982 (and maybe earlier?) BBN
arranged for NCP "brown-outs" to encourage speedy development.

On 2023-09-28 08:09, Lars Brinkhoff wrote:
> Johnny Billquist wrote:
>> Dan Cross wrote:
>>>> In fact, were there any [VAXen] at all on the ARPANET before the
>>>> 1983 flag day?
>>> Almost certainly. The initial TCP/IP implementation work for Unix
>>> was being done at BBN at the time, and I imagine that meant VAXen
>>> connected to ARPANET.
>
> I meant VAX machines talking the NCP protocol.
>
>> Well, before flag day, ARPANET wasn't speaking TCP/IP...
>
> Yet, there were experiments with TCP long before the flag day so it's
> not a 100% either/or situation. I get the feeling (but I have no
> evidence handy) some subset of nodes got started using TCP before NCP
> was shut down. On several occasions in 1982 (and maybe earlier?) BBN
> arranged for NCP "brown-outs" to encourage speedy development.

There were of course development, and testing done between machines and
so on. But that was not "ARPANET". ARPANET was running NCP until flag
day, when it officially switched to IP. And at some point after that,
all of ARPANET because just the 10.* addresses on the Internet, and then
ARPANET was turned off, and it was decided that 10.* should not exist on
the Internet anymore...

Johnny

On Thu, 2023-09-28 at 12:58 +0200, Johnny Billquist wrote:
> There were of course development, and testing done between machines
> and so on. But that was not "ARPANET". ARPANET was running NCP until
> flag day, when it officially switched to IP. And at some point after
> that, all of ARPANET because just the 10.* addresses on the Internet,
> and then ARPANET was turned off, and it was decided that 10.* should
> not exist on the Internet anymore...

That 10.* address range still lives on in private networks to this very
day. Hadn't realised until now that ARPAnet actually had that address
range.
--
Tactical Nuclear Kittens

On 2023-09-28 14:04, Single Stage to Orbit wrote:
> On Thu, 2023-09-28 at 12:58 +0200, Johnny Billquist wrote:
>> There were of course development, and testing done between machines
>> and so on. But that was not "ARPANET". ARPANET was running NCP until
>> flag day, when it officially switched to IP. And at some point after
>> that, all of ARPANET because just the 10.* addresses on the Internet,
>> and then ARPANET was turned off, and it was decided that 10.* should
>> not exist on the Internet anymore...
>
> That 10.* address range still lives on in private networks to this very
> day. Hadn't realised until now that ARPAnet actually had that address
> range.

Yes. It's a private range for exactly the reason that when ARPANET was
decomissioned/turned off, its address range was decided to not be
reused. Which made it available for private use as it is today.

One bit of ARPANET still exists today. The weird reverse DNS lookups on
IP addresses are done within the arpa.net domain. :-)

Gromit:/Users/johnny.billquist> nslookup -query=ptr 8.8.8.8.in-addr.arpa.net
Server: 195.186.1.111
Address: 195.186.1.111#53

Non-authoritative answer:
8.8.8.8.in-addr.arpa.net name = localhost.

Authoritative answers can be found from:

Johnny

On Thursday, September 28, 2023 at 7:20:55 AM UTC-7, Johnny Billquist wrote:

(snip)

> One bit of ARPANET still exists today. The weird reverse DNS lookups on
> IP addresses are done within the arpa.net domain. :-)
>
> Gromit:/Users/johnny.billquist> nslookup -query=ptr 8.8.8.8.in-addr.arpa.net
> Server: 195.186.1.111
> Address: 195.186.1.111#53
>
> Non-authoritative answer:
> 8.8.8.8.in-addr.arpa.net name = localhost.

All the ones I have are in-addr.arpa. No .net on them.

On Thu, 2023-09-28 at 09:57 -0700, gah4 wrote:
> > One bit of ARPANET still exists today. The weird reverse DNS
> > lookups on IP addresses are done within the arpa.net domain. :-)
> >
> > Gromit:/Users/johnny.billquist> nslookup -query=ptr 8.8.8.8.in-
> > addr.arpa.net
> > Server: 195.186.1.111
> > Address: 195.186.1.111#53
> >
> > Non-authoritative answer:
> > 8.8.8.8.in-addr.arpa.net name = localhost.
>
> All the ones I have are in-addr.arpa.   No .net on them.

$ nslookup -query=ptr 8.8.8.8.in-addr.arpa.net
net.c:537: probing sendmsg() with IPV6_TCLASS=b8 failed: Network is
unreachable
Server: 192.168.2.254
Address: 192.168.2.254#53

Non-authoritative answer:
8.8.8.8.in-addr.arpa.net name = localhost.

Not here it is :)
--
Tactical Nuclear Kittens

On Thursday, September 28, 2023 at 11:01:22 AM UTC-7, Single Stage to Orbit wrote:
> On Thu, 2023-09-28 at 09:57 -0700, gah4 wrote:

(snip)

> > All the ones I have are in-addr.arpa. No .net on them.

> $ nslookup -query=ptr 8.8.8.8.in-addr.arpa.net
> net.c:537: probing sendmsg() with IPV6_TCLASS=b8 failed: Network is
> unreachable
> Server: 192.168.2.254
> Address: 192.168.2.254#53
> Non-authoritative answer:
> 8.8.8.8.in-addr.arpa.net name = localhost.
> Not here it is :)

But it gives the wrong answer!

> 8.8.8.8
Server: 127.0.0.1
Address: 127.0.0.1#53

Non-authoritative answer:
8.8.8.8.in-addr.arpa name = dns.google.

In my few tries, the in-addr.arpa.net always returns localhost.

in-addr.arpa, the one it has been for years, decades, returns
the right answer.

In article <uf3m7s$lv$4@news.misty.com>,
Johnny Billquist <bqt@softjar.se> wrote:
>On 2023-09-28 08:09, Lars Brinkhoff wrote:
>> Johnny Billquist wrote:
>>> Dan Cross wrote:
>>>>> In fact, were there any [VAXen] at all on the ARPANET before the
>>>>> 1983 flag day?
>>>> Almost certainly. The initial TCP/IP implementation work for Unix
>>>> was being done at BBN at the time, and I imagine that meant VAXen
>>>> connected to ARPANET.
>>
>> I meant VAX machines talking the NCP protocol.
>>
>>> Well, before flag day, ARPANET wasn't speaking TCP/IP...
>>
>> Yet, there were experiments with TCP long before the flag day so it's
>> not a 100% either/or situation. I get the feeling (but I have no
>> evidence handy) some subset of nodes got started using TCP before NCP
>> was shut down. On several occasions in 1982 (and maybe earlier?) BBN
>> arranged for NCP "brown-outs" to encourage speedy development.
>
>There were of course development, and testing done between machines and
>so on. But that was not "ARPANET". ARPANET was running NCP until flag
>day, when it officially switched to IP.

....and for a while after that, too!

>And at some point after that,
>all of ARPANET because just the 10.* addresses on the Internet, and then
>ARPANET was turned off, and it was decided that 10.* should not exist on
>the Internet anymore...

What you wrote above is certainly true, but given that the
ARPANET was the original Internet backbone and that the initial
TCP work for VAX Unix was being done at BBN, it's not
unreasonable to believe that they did an NCP implementation for
the VAX before TCP/IP proper. Of course, that's speculation (I
have no evidence) but it's not unreasonable.

- Dan C.

In article <e1bcd5f3-807f-46bc-bfcb-f7a26e669a03n@googlegroups.com>,
gah4 <gah4@u.washington.edu> wrote:
>On Thursday, September 28, 2023 at 11:01:22 AM UTC-7, Single Stage to Orbit wrote:
>> On Thu, 2023-09-28 at 09:57 -0700, gah4 wrote:
>
>(snip)
>
>> > All the ones I have are in-addr.arpa. No .net on them.
>
>> $ nslookup -query=ptr 8.8.8.8.in-addr.arpa.net
>> net.c:537: probing sendmsg() with IPV6_TCLASS=b8 failed: Network is
>> unreachable
>> Server: 192.168.2.254
>> Address: 192.168.2.254#53
>> Non-authoritative answer:
>> 8.8.8.8.in-addr.arpa.net name = localhost.
>> Not here it is :)
>
>But it gives the wrong answer!
>
>> 8.8.8.8
>Server: 127.0.0.1
>Address: 127.0.0.1#53
>
>Non-authoritative answer:
>8.8.8.8.in-addr.arpa name = dns.google.
>
>
>In my few tries, the in-addr.arpa.net always returns localhost.
>
>in-addr.arpa, the one it has been for years, decades, returns
>the right answer.

The correct domain for reverse DNS lookup is in-addr.arpa. It
looks like the `arpa.net` is just a normal domain (if a
surprising one).

- Dan C.

Johnny Billquist wrote:
> There were of course development, and testing done between machines
> and so on. But that was not "ARPANET". ARPANET was running NCP until
> flag day, when it officially switched to IP.

NCP and TCP operated in parallel on the ARPANET for a while. The
Internet Protocol Transition Workbook from November 1981 encouraged new
hosts to only implement TCP, not NCP, and says at that point there were
TCP-only hosts. On several occasions during 1982, NCP was temporarily
blocked, but TCP was allowed. What happened on flag day was that NCP
was permanently blocked.

So what I was wondering was: were there any VAXen talking NCP, or did
they jump straight to TCP? I'd like to see evidence, not handwaving.

In article <7wh6nehycy.fsf@junk.nocrew.org>,
Lars Brinkhoff <lars.spam@nocrew.org> wrote:
>Johnny Billquist wrote:
>> There were of course development, and testing done between machines
>> and so on. But that was not "ARPANET". ARPANET was running NCP until
>> flag day, when it officially switched to IP.
>
>NCP and TCP operated in parallel on the ARPANET for a while. The
>Internet Protocol Transition Workbook from November 1981 encouraged new
>hosts to only implement TCP, not NCP, and says at that point there were
>TCP-only hosts. On several occasions during 1982, NCP was temporarily
>blocked, but TCP was allowed. What happened on flag day was that NCP
>was permanently blocked.
>
>So what I was wondering was: were there any VAXen talking NCP, or did
>they jump straight to TCP? I'd like to see evidence, not handwaving.

This came up on the TUHS list back in 2021 (you were on the
thread, Lars). That pointed to this:

https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-Vax-TCP/history

Which stronly implies that there was some "NCP" in VAX Unix
sometime in 1980. Whether that was the Network Control Protocol
or just an affectation for "networking code" (as implied by Noel
Chiappa in the TUHS thread) is unknown.

- Dan C.

On 2023-09-28 18:57, gah4 wrote:
> On Thursday, September 28, 2023 at 7:20:55 AM UTC-7, Johnny Billquist wrote:
>
> (snip)
>
>> One bit of ARPANET still exists today. The weird reverse DNS lookups on
>> IP addresses are done within the arpa.net domain. :-)
>>
>> Gromit:/Users/johnny.billquist> nslookup -query=ptr 8.8.8.8.in-addr.arpa.net
>> Server: 195.186.1.111
>> Address: 195.186.1.111#53
>>
>> Non-authoritative answer:
>> 8.8.8.8.in-addr.arpa.net name = localhost.
>
> All the ones I have are in-addr.arpa. No .net on them.

You are right. I don't know where I got the ".net" from, and I'm
surprised it worked...

Johnny

On 2023-09-28 21:43, Dan Cross wrote:
> In article <uf3m7s$lv$4@news.misty.com>,
> Johnny Billquist <bqt@softjar.se> wrote:
>> And at some point after that,
>> all of ARPANET because just the 10.* addresses on the Internet, and then
>> ARPANET was turned off, and it was decided that 10.* should not exist on
>> the Internet anymore...
>
> What you wrote above is certainly true, but given that the
> ARPANET was the original Internet backbone and that the initial
> TCP work for VAX Unix was being done at BBN, it's not
> unreasonable to believe that they did an NCP implementation for
> the VAX before TCP/IP proper. Of course, that's speculation (I
> have no evidence) but it's not unreasonable.

Very definitely possible. And it's probably even possible to find
concrete information if you dig through the old RFCs. I know there are
ones which are just listing machines and OSes that are capable to
interoperate on the ARPANET. But I've read through them so many times I
don't care to do it again right now. :-)

Johnny

On 2023-09-28 21:49, Lars Brinkhoff wrote:
> Johnny Billquist wrote:
>> There were of course development, and testing done between machines
>> and so on. But that was not "ARPANET". ARPANET was running NCP until
>> flag day, when it officially switched to IP.
>
> NCP and TCP operated in parallel on the ARPANET for a while. The
> Internet Protocol Transition Workbook from November 1981 encouraged new
> hosts to only implement TCP, not NCP, and says at that point there were
> TCP-only hosts. On several occasions during 1982, NCP was temporarily
> blocked, but TCP was allowed. What happened on flag day was that NCP
> was permanently blocked.
>
> So what I was wondering was: were there any VAXen talking NCP, or did
> they jump straight to TCP? I'd like to see evidence, not handwaving.

How would they interoperate? TCP and NCP are not exactly compatible in
any way.

You would basically have to have two different parallel networks, and
them you might have some machines that would act as gateway between the
two networks.

Johnny

On 2023-09-28 21:59, Dan Cross wrote:
> In article <7wh6nehycy.fsf@junk.nocrew.org>,
> Lars Brinkhoff <lars.spam@nocrew.org> wrote:
>> Johnny Billquist wrote:
>>> There were of course development, and testing done between machines
>>> and so on. But that was not "ARPANET". ARPANET was running NCP until
>>> flag day, when it officially switched to IP.
>>
>> NCP and TCP operated in parallel on the ARPANET for a while. The
>> Internet Protocol Transition Workbook from November 1981 encouraged new
>> hosts to only implement TCP, not NCP, and says at that point there were
>> TCP-only hosts. On several occasions during 1982, NCP was temporarily
>> blocked, but TCP was allowed. What happened on flag day was that NCP
>> was permanently blocked.
>>
>> So what I was wondering was: were there any VAXen talking NCP, or did
>> they jump straight to TCP? I'd like to see evidence, not handwaving.
>
> This came up on the TUHS list back in 2021 (you were on the
> thread, Lars). That pointed to this:
>
> https://www.tuhs.org/cgi-bin/utree.pl?file=BBN-Vax-TCP/history
>
> Which stronly implies that there was some "NCP" in VAX Unix
> sometime in 1980. Whether that was the Network Control Protocol
> or just an affectation for "networking code" (as implied by Noel
> Chiappa in the TUHS thread) is unknown.

I have obviously no idea. But one also have to be careful that DECnet
don't get mixed in here, since there is also an NCP there. And Ultrix
talked DECnet on VAXen. Not sure when that came about, though...

Johnny

On Thursday, September 28, 2023 at 2:43:28 PM UTC-7, Johnny Billquist wrote:

(snip)

> You would basically have to have two different parallel networks, and
> them you might have some machines that would act as gateway between the
> two networks.

I don't remember back to NCP, but I do remember exactly that
for DECnet and TCP/IP. There were gateways that would transfer
mail between the two. I believe also some that would allow
remote login between the two.

Johnny Billquist wrote:
>> NCP and TCP operated in parallel on the ARPANET for a while.
> How would they interoperate? TCP and NCP are not exactly compatible in
> any way.

Details are found in the "Internet Protocol Transition Workbook".

> you might have some machines that would act as gateway between the two
> networks.

That's exactly what they did.