[Css-csts] possibility of valid monitored parameter values for non-"active" functinal resources

[John Pietras]

Martin,

During the review of the MD-CSTS last week in Noordwijk, you made a comment on the following sentence, which appeared in section 2.5.2:

"In providing the MD-CSTS, the Complex cyclically returns measured values for the all instances of the subscribed monitored parameters for all active functional resource instances."

 

You pointed out that a functional resource might not be "active" (in the sense that it is specifically configured as part of the Service Package) and yet it still might emit valid monitored parameter measurements. You suggested that a note to this effect be included in the MD-CSTS.

 

In thinking about how to construct and incorporate such a note, I have realized that the sentence in question is itself incorrectly phrased. It is a remnant of the concept that I had previously proposed, in which only parameters associated with "active" functional resources would be reported and NO values would be reported for inactive resources (in order to reduce the amount of data being reported). In telecons earlier in the fall, we decided that such filtering by "active" resources was problematic and we dropped the notion, falling back to the concept as defined in the Framework - if a parameter is subscribed to, some value (valid, 'undefined', 'unavailable', or 'error') is returned for it in every report.

 

So the above sentence should read simply:

 "In performing the Cyclic Report procedure of the MD-CSTS, the Complex cyclically returns measured values for all of the subscribed monitored parameters for that procedure instance." 

 

That is how I have changed it for the next version of MD-CSTS (note that the sentence contains other changes to comply with another comment made regarding it). 

 

Given that there is now no distinction made for "active" functional resources, I think the note that you recommended is not necessary. A valid value for a subscribed parameter is either available or unavailable for a given sampling period, without regard to whether the resource that produces it is supposed to be "active" at the time. 

 

So my plan is to not address the issue beyond making the above change to the sentence. If you think that it is still necessary or useful to make such a note, I contend that it is a general possibility for any CSTS that returns qualified-parameters values (not just MD-CSTS), and should therefore be addressed in a note in the Framework itself.

 

Best regards,

John

 

 

John Pietras

GST, Inc. 

7855 Walker Drive, Suite 200

Greenbelt, MD 20770

240-542-1155

 

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