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Representation language review

One of the physical components of a SAFE product, are the XML Schema files. These files provide the representation information of the data held by a SAFE product. In order to represent the binary information, SAFE defines specific markups that annotate the XML Schema documents to provide information on the physical structure, i.e. the so-called SDF markups. Thanks to these specific annotations, the contents of the binary files are described up to the bit level with a common technique as for XML documents.

SDF (Structured Data File) is XML based and provides bit-level description but it is a proprietary language not standardised.

A new standard and/or open language should be analysed to be adopted for data file representation in the new SAFE specification.

Other candidates currently used for archiving technology shall be considered if they are identified.


Re: Representation language review


> A new standard and/or open language should be analysed to be adopted for data file representation in the new SAFE specification.
>

Found a possible candidate from the Open Grid Forum:

Data Format Description Language
http://www.ogf.org/dfdl/

I don't know anything about it, but first impressions are that it does the same thing as the SDF types in SAFE.


Re: Re: Representation language review

>
> > A new standard and/or open language should be analysed to be adopted for data file representation in the new SAFE specification.
> >
>
> Found a possible candidate from the Open Grid Forum:
>
> Data Format Description Language
> http://www.ogf.org/dfdl/
>
> I don't know anything about it, but first impressions are that it does the same thing as the SDF types in SAFE.

Yes, DFDL is very similar to SDF and it's one of the main alternatives we are considering at the moment. There are some features that have to be clarified yet (e.g. data representation at bit-level) but it seems that could fulfill the needs for SAFE. One of the main constraints we have identified is that the specification is one year-old only and it is uncertain how stable can be.

However, it is a good candidate and would be analysed for the PDR-C

Other alternatives we are considering are EAST/DEDSL, BinX or PADS/ML so any feedback on the operational experience using this formats would be appreciated.



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