Re: Removing ARCNET stuffs

[<Paul_Koning%Dell.com@localhost>]

> On May 29, 2015, at 6:22 AM, Johnny Billquist <bqt%Update.UU.SE@localhost> wrote:
> 
> On 2015-05-29 08:18, Matt Thomas wrote:
>> ...
>> 
>> I have a Phase IV+ (so I didn’t have to much with the physical address) implementation but never got around to writing the apps.  socket interface is identical to DECnet-ULTRIX.  DAP is a beast as is CTERM.  I could run IP protocols over, but then I have IP for that. :)
> 
> If you say that you didn't fiddle with physical addresses, then you have been playing Phase V, as Phase IV requires that you manipulate the physical address. And that is also true of IV+.

Maybe Matt meant IV-prime?  That’s an obscure variant of Phase IV invented to allow DECnet to run on 802.5 networks.  I recently found a spec for it.  It isn’t all that hard; the changes are just in the routing layer.  And yes, it allows you to keep your physical address, so long as all the neighbors you need to talk to also run IV-prime.

Of course, if you have a LAN driver and interface that supports multiple individual addresses, you can use the HIORD style address for DECnet while keeping the conventional physical address for other protocols.  Most hardware supports this, actually, though it’s not clear how many drivers do.
> 
> DAP would be really nice, but it's complex. But I like the capabilities.

I wouldn’t have thought of DAP as all that complex; after all it fits in PDP11 systems.  You can probably subset it pretty nicely if you don’t need all the features.  Just file transfer, as opposed to transparent file I/O, is likely to simplify things substantially.  The DECnet/Linux implementation of DAP does this, I believe, and it does a reasonably good job.  I think I even got it to talk successfully to a RSTS/E system at one time.

	paul