[HECnet] ANF10 network --> DN200 (RJE, Decnet) --> should be Ddcmp --> Re:4 --> Cryptic -->Dup11 simh only for Ddcmp --> update

[R. Voorhorst]

Before I get a storm this from Pdp11_dup.c should accompany it:

   The wire protocol implemented is native DDCMP WITHOUT the DDCMP SYNC 
   characters both initially and between DDCMP packets.

-----Original Message-----
From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] On Behalf
Of R. Voorhorst
Sent: Friday, 19 November, 2021 20:42
To: hecnet at Update.UU.SE
Cc: Mark at infocomm.com
Subject: RE: [HECnet] ANF10 network --> DN200 (RJE, Decnet) --> should be
Ddcmp --> Re:4 --> Cryptic -->Dup11 simh only for Ddcmp

Yes, that is how Pdp10 KS10 and Vax and Rsx and Rsts all interface to the
Dmc/Dmr offered layer and for Anf10 on Pdp10 as well.
But trying Decnet on bare Dup11 will reveal all.

However this will fail on simh: look at the comment in Pdp11_dup.c from Bob:

   dup          DUP11 Unibus/DPV11 Qbus bit synchronous interface

   This module implements a bit synchronous interface to support DDCMP.
Other
   synchronous protocols which may have been supported on the DUP11/DPV11
bit 
   synchronous interface are explicitly not supported.

So the 0,01 % rises to 100% that it will not work as bare sync device

-----Original Message-----
From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] On Behalf
Of Paul Koning
Sent: Friday, 19 November, 2021 17:23
To: hecnet at update.uu.se
Subject: Re: [HECnet] ANF10 network --> DN200 (RJE, Decnet) --> should be
Ddcmp --> Re:4 --> Cryptic

I assume it means that RSX (and RSTS too) lets you use a DMC directly from
an application as an I/O device you can open.  If so, you get a packet
service that lets you transmit whatever packets you want, which will be sent
encapsulated in DDCMP protocol.  In the RSX case I'd assume that includes
support for maintenance mode (in RSTS that isn't supported).

	paul

> On Nov 19, 2021, at 11:14 AM, R. Voorhorst <R.Voorhorst at swabhawat.com>
wrote:
> 
> Please can you explain your second sentence somewhat? I read:  "... the
Ddcmp layer ... it does present it as a device ...". I do not perceive the
connotation. 
> 
> 
> Reindert
> 
> -----Original Message-----
> From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE] On
Behalf Of Johnny Billquist
> Sent: Friday, 19 November, 2021 14:46
> To: hecnet at Update.UU.SE
> Subject: Re: [HECnet] ANF10 network --> DN200 (RJE, Decnet) --> should be
Ddcmp --> Re:4
> 
> RSX definitely can use a DUP11 standalone through DECnet. In which case
it's software side DDCMP.
> 
> Heck, you can also use the DDCMP layer yourself, without involving DECnet.
It does present it as a device to the system on which you can send/receive
packets.
> 
>   Johnny