[MOIMS-NAV-EXEC] FW: TDM and off-line validated radiometric data

[Berry, David S (3920)]

All:

So... in the aftermath of the presentation last week from the Cross-Support Services, there was some "complaining" in the CESG meeting that we were not supporting their effort.

See below for the intervention from my project manager here at JPL, who is also a member of the CESG.  I'd be interested in any comments from you on these topics.

Regards,
David




From: David Berry <david.s.berry at jpl.nasa.gov<mailto:david.s.berry at jpl.nasa.gov>>
Date: Friday, April 15, 2016 at 10:16 AM
To: "Shames, Peter M (312B)" <peter.m.shames at jpl.nasa.gov<mailto:peter.m.shames at jpl.nasa.gov>>
Cc: "Barkley, Erik J (3970)" <erik.j.barkley at jpl.nasa.gov<mailto:erik.j.barkley at jpl.nasa.gov>>, "Tai, Wallace S (9000)" <wallace.s.tai at jpl.nasa.gov<mailto:wallace.s.tai at jpl.nasa.gov>>
Subject: Re: TDM and off-line validated radiometric data


Peter:  My comments are inline with your questions/comments, prefaced with my initials "DSB".

David



From: "Shames, Peter M (312B)" <peter.m.shames at jpl.nasa.gov<mailto:peter.m.shames at jpl.nasa.gov>>
Date: Thursday, April 14, 2016 at 4:23 PM
To: David Berry <david.s.berry at jpl.nasa.gov<mailto:david.s.berry at jpl.nasa.gov>>
Cc: "Barkley, Erik J (3970)" <erik.j.barkley at jpl.nasa.gov<mailto:erik.j.barkley at jpl.nasa.gov>>, "Tai, Wallace S (9000)" <wallace.s.tai at jpl.nasa.gov<mailto:wallace.s.tai at jpl.nasa.gov>>
Subject: TDM and off-line validated radiometric data

Hi David,

During the CESG meeting a discussion of the subject of TDM support for off-line validated radiometric data came up.  The assertion is that it does not offer all of the needed features to document what is done to validate the data, and that therefore some added annotations are needed.

DSB:  I have never seen a set of requirements for the "Validated Radiometric Service", whatever that is, nor has the Navigation WG been consulted on this topic (though we did see a presentation at the recent Spring Meetings). The process of validating data was of course discussed during the creation of the original TDM, and it was agreed that any discussion of validation procedures was sufficiently complex that, if necessary, would be described in an ICD (or as CSS calls it, a "bilateral agreement").

These could be handled in a variety of ways:

1. Extending the TDM in some natural way to include these added data prior to  transfer using TGFT.
DSB:  I do not know why these "annotations" are necessary in order to transfer the data. It is unclear to me (and other members of the Navigation WG) why it is necessary to modify the published TDM standard in order to perform what is essentially a file transfer. In short, this boils down to something like: "if this is a Generic File Transfer, then just transfer the file, whatever it is".

2. Creating a new “validated radiometric” annotations file that would be appended to the TDM and  transferred using TGFT.

DSB:  The TDM has a "DATA_QUALITY" keyword that has 3 normative values:  "RAW", "DEGRADED", "VALIDATED".  I would assume that any TDM constituting part of the "Validated Radiometric Service", whatever that is, would include this keyword/value combination.

3. Creating some new meta-data file to annotate the vaiidated radiometric data for transfer using TGFT.

DSB:    I have never seen a set of requirements for the "Validated Radiometric Service", whatever that is, nor has the Navigation WG been consulted on this topic (though we did see a presentation at the recent Spring Meetings). Therefore I am not aware of the rationale for a requirement annotations.

There may be other options as well.  Questions for you are these:

1. Is it the case that TDM, out of the box, cannot support validated radiometric data?

DSB:  Not true. The TDM has been successfully used for a number of interagency missions over the past several years.  Presumably these data were valid.

2. Is there any intent to remedy that, or conversely, any way within the existing TDM structures, to add the needed data (option 1)?

DSB:  The need for added data has not been established in the opinion of the Navigation WG.

3. Is the Nav WG willing to take up the work to extend TDM to accommodate this added info?

DSB:  The need for added data has not been established in the opinion of the Navigation WG. While we are in discussion of a small number of data types that will be added in the current revision process, we have not seen a rationale to add data for said "Validated Radiometric Service", whatever that is, and do not see why the content of a file needs to be changed in order to transfer it with a generic file transfer application.

4. Is the Nav WG willing to take up the work to define an extended TDM annotations file accommodate this added info (option 2)?

DSB:  Perhaps, but before a commitment can be made it would be necessary to firmly establish the need for said annotations.

5. Is the Nav WG willing to take up the work to define a meta-data file to annotate the vaiidated radiometric data for transfer using TGFT (option 3)?

DSB:  The structure of the TDM already contains the metadata that describes the data. There is no need for any external metadata file.

If the TDM cannot handle this case I think we all would prefer option 1, where the existing file structures would just be extended to embed the needed annotations and TGFT transfer could be directly used without any attached file or added directions of any sort.

DSB:  Who exactly is "we"?  Please explain the requirement for annotations.  Please explain why a "generic file transfer" application doesn't just transfer whatever file is presented to it?

What do you think?

Thanks, Peter

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