[Info-vax] Reading Gordon Bell's VAX strategy document

[Johnny Billquist]

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