> On Mar 3, 2026, at 9:36 PM, Phil Budne via cctalk <[email protected]>
> wrote:
>
> Paul Koning wrote:
>> NCP as a standardized element, with its protocol NICE, arrived in Phase III.
>> I was somewhat surprised to find a predecessor of both the program and the
>> protocol in Phase II for TOPS-20
>
> I'm 99.44% sure that in Phase III days both PDP-10 operating systems
> were still non-routing Phase II nodes with only one link to a
> dedicated front end PDP-11 (via the DTE hardware that could handle
> upto four). Before Phase III everything had to be manually routed,
> A::B::C -- I forget the name of the passthru service that facilitated
> that.
The front end thing is called "intercept" which implements a rudimentary form
of routing documented in an appendix of the Phase II spec. PyDECnet implements
it (in a branch at least; I forgot if it's released yet).
But that doesn't use the A::B::C stuff you mentioned. That's a different
mechanism handled in the application (in some of them) using a DEC internal
object called PMR (poor man's routing) or PSTHRU. That actually was carried
over all the way to Phase IV within DEC in order to access "hidden areas".
Some applications would get equivalent functionality a different way. For
example, it would work in DAP if the intermediate node was VMS, because VMS
(RMS32) has transparent network access.
paul
