[Smwg] Simple Schedule Recommendation - Draft Red 1.03

John Pietras john.pietras at gst.com
Wed Feb 11 21:44:24 UTC 2015

Colin and CSSMWG colleagues ---
Regarding finishing the XML schema, there are two items that we have to decide on:
1.  The namespace question. I don't think that it is going to be a big issue, but we deferred discussing it at yesterday's telecon until sometime in the future (I can't remember when). With regard to the Simple Schedule,  I think that the decision could come down to whether we use two or three namespaces. In the two-namespace option, one would be dedicated to Simple-Schedule-specific schema, and the second would hold stuff that is common to multiple SCCS-SM schemas. This common set would include the three types common to all Info Entities (SrvMgtInfoEntity, SrvMgtHeader, and SrvMgtData) as well as the other lower-level types that we have defined (e.g., CcsdsAsciiTimeCodeBType, String1024Type). The three-namespace option splits the common types into separate namespaces: one for the common Info Entity types and the other for the lower-level types. There may also be other ways to cut the namespace pie.

2. How we represent the "stereotype" structure of Info Entities (SrvMgtInfoEntity contains SrvMgtHeader and  SrvMgtData) in XML schema. I had posted my briefing on the CWE about the two approaches that I had considered, and so far Anthony is the only person to have responded. The first approach that I had looked at would have the concrete Info Entity schemas inherit not only the top-level types (SrvMgtInfoEntity, SrvMgtHeader, and SrvMgtData) but also the containment relationships among them. In other words, XML validation would enforce that any Info Entity schema have its SrvMgtInfoEntity-derived class contain a SrvMgtHeader-derived class and a SrvMgtData-derived class. However, this approach does introduce a bit of structural complexity.

The second approach that I looked at did not inherit the containment relationship. Instead, composition rules would have to be included that state that the SrvMgtInfoEntity-derived class for the XYZ Info Entity must contain a SrvMgtHeader-derived class and a SrvMgtData-derived class. The XML schema structure itself is simpler than the one that inherits the containment relationships. I believe that Anthony was showing a preference for the simpler-structure second approach, and I have no problem with that. 

Best regards,

-----Original Message-----
From: smwg-bounces at mailman.ccsds.org [mailto:smwg-bounces at mailman.ccsds.org] On Behalf Of Colin.Haddow at esa.int
Sent: Wednesday, February 11, 2015 12:14 PM
To: CCSDS Service Mgmt WG
Subject: [Smwg] Simple Schedule Recommendation - Draft Red 1.03

Dear all,
                  I've just uploaded the latest draft of the Simple Schedule Red Book, this takes into account the comments from the last few telecons, including Marcins diagrams, matrix of allowed parameter combinations etc.
Comments welcome, hopefully there wont be too many, as it should be pretty much finished, I think about the only thing remaining is for John to update the XML schema in Annex C. The document, model and diagrams can be found at the following URLs.




Cheers for now,



Dr. Colin R. Haddow,
HSO-GI, European Space Agency,
European Space Operations Centre,
Robert-Bosch-Str 5,
64293 Darmstadt,

Phone; +49 6151 90 2896
Fax;      +49 6151 90 3010
E-Mail;  colin.haddow at esa.int

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