[Moims-dai] FW: CESG conditions on your OIAS Reference Model, CCSDS 650.0-P-2.0

[david at giaretta.org]

We should talk about this at the meeting.

 

..David

 

From: Shames, Peter M (US 312B) <peter.m.shames at jpl.nasa.gov> 
Sent: 13 January 2020 21:08
To: David Giaretta <david at giaretta.org>
Subject: CESG conditions on your OIAS Reference Model, CCSDS 650.0-P-2.0

 

Hi David,

 

I just want to alert you that as I started reading this document as part of the CESG review that I, almost immediately as it turned out, stumbled over some issues of terminology and content that I thought needed to be addressed.  These were significant enough that they tipped me into "give this a serious reading" mode.  Right now I am on pg 71 and I have thirteen (13) RIDs queued up.  Some of them are going to take a bit of work to fix, so I wanted to alert you.

 

One of them, which I have not yet written up, concerns the approach that you have used vis-à-vis the definition of OAIS services and service interfaces.  This is a Magenta Book, which gives you some amount of latitude in just what is included.  As such, this is mostly about procedures and processes, but you do define a sort of abstract data system model, with functional elements, service interfaces (some internal and some external), and data flows (some with named data objects with their own abstract definitions like AIP, SIP, and DIP).  All of this is abstract, and it is fine that this is the case in a Magenta Book.  If they were concrete definitions you would be in Blue Book territory and I believe that you do not want to go there.

 

That said, I do think that you are missing a fine opportunity to provide some further, and very useful in my opinion, abstract definitions of these service interfaces.  The work that was published in the CCSDS Reference Architecture for Space Information Management (RASIM), CCSDS 312.0-G-1 (attached for reference), provides a set of straightforward, but still abstract, functional interfaces for exactly the sorts of registry, repository, query, etc interfaces that this OAIS model mentions, but does not clearly define.  I happen to be of the opinion that including such definitions for these fundamental functional (but abstract) building block objects, and for service interfaces (also abstract) that reference them would be a huge improvement in the document.  Now, it is true that I am biased, that work occurred in a WG in my Area and I contributed to it, but I also think I am being objective when I suggest that your document would be significantly enhanced in value by these technical, but abstract, additions.

 

I would even go so far as to propose that I help your WG in making these additions to the document.  That's up to you and your team, of course, but it is a sincere offer.

 

That said, I will be bringing all of these concerns to your WG in the form of Conditions on publication.  What you choose to do with them, and how you disposition them, is really your business and this is neither a threat nor a bribe, just an honest expression of concern and a set of technical issues to be discussed and resolved.

 

I am happy to discuss any of this, either now or after I submit the CESG conditions.

 

Best wishes, Peter

 

 

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