[Info-vax] Reject Cause=Invalid Message Format, Erroneous Transport PDU='386200BD00000005'H

[Dirk Munk]

Scott Dorsey wrote:
> Supratim Sanyal wrote:
>> Hi,
>>
>> I am no network expert and looking for help.
>>
>> Two SIMH OpenVMS 7.3 DECnet Plus nodes - QCOCAL (1.550) and CLOUDY
>> (1.551), connected over Johnny's UDP bridge. FAL directories across the
>> network work fine. However I cannot get NCP status from the remote host
>> from either. Also the circuits do not seem to be setting themselves up,
>> I don't know if that is a cause or effect of the Remote Protocol Errors.
>>
>> Note: A SIMH PDP-11/24 (JUICHI, 1.552) runnign RSX-11M-PLUS is colocated
>> (running on the same linux host) with CLOUDY, and NCP queries somehow
>> work fine to it.
>
> RSX-11+ supports Phase V?
> I don't think it does.
>
> So, if the query is working on the RSX-11 node, it is likely a Phase IV
> query.  And likely won't work on the Phase V node.
>
> Mixing Phase V and Phase IV can be done but is best avoided.
> --scott
>

He didn't say that the RSX node is running Phase V, it clearly is 
running Phase IV.

What he is showing is this:

You can use NCP on a Phase V node to get information from a Phase IV node.

You can use NCP on a Phase V node to get some (rather bogus) Phase IV 
information of that same node. Phase V information is somehow 
'translated' into Phase IV information.

You can not use NCP to get similar 'bogus' Phase IV information from 
another Phase V node.

I'm not surprised.

DECnet information of a Phase V node should be retrieved with NCL, not 
NCP. The same applies to Phase V information from another Phase V node.