[HECnet] Oldest VAX/VMS for VAX-11/730 on HECNET

[Johnny Billquist]

On 2021-12-09 22:03, Paul Koning wrote:
> 
> 
>> On Dec 9, 2021, at 3:33 PM, Mark J. Blair <nf6x at nf6x.net> wrote:
>>
>>
>>
>>> On Dec 9, 2021, at 11:00 AM, Paul Koning <paulkoning at comcast.net> wrote:
>>>
>>> BTW, the original request asks for the oldest VMS for a 730 on HECnet, and mentions Phase IV.  That's certainly friendliest and it is of course required if you want to connect by Ethernet.  But Phase III can also be used, and Phase II provided you have either a Phase III or a PyDECnet neighbor to connect it to.
>>
>> Really?! How can they talk to a remote node with an area number and larger node address numbers than they are designed for?
> 
> You don't directly, that's the nature of the beast.  For selected applications "poor man's routing" lets you get there from here.  For example, with file access (thanks to VMS RMS transparent remote access) you could do something like:
> 
> 	type helper::far::foo.txt
> 
> where "helper" is a directly reachable VMS node.  Some other applications may do the analogous thing using the "passthrough" (a.k.a., "poor man's routing") helper, which is an application that relays connections.  I need to reverse-engineer its protocol, it's pretty simple.  TOPS-20 has one, as I recall (which also can do ANF-10 -- or was that TOPS-10?).  So does RSTS; I know VMS had one but I don't know if it shipped with the product or was only a DEC internal tool.  It certainly got a great deal of use in the Phase III era, and later on was resurrected to handle "hidden areas" in DEC's internal network.

To answer Mark in another way - you can't. Not directly. A phase III 
node can only talk to phase IV nodes in the same area, and that have a 
node number below 255 in the area.

But with PMR you basically just use names, and you only need to be able 
to talk with the first hop. Anything beyond that is dealt with by the 
next hop. So with that you can get around the problem. The same is true 
for phase IV nodes in a phase V network.

RSX have PMR as well. I've never looked much into how to use it, but I 
know it has its own object number. But things like MAIL11 does it in the 
application itself. Other programs I don't know. You'd probably need to 
check both the specific program, and the specific OS about it.

   Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol