A note on a possible extension to SIAP

[Alberto Micol]

> Thank you Alberto, good question. In fact, maybe we could broaden the
> question to the one we should start with -- What are the Use Cases for 
> SIAP?

Well, I took for granted that a "Display Data Model", as sometimes the 
metadata tree is refer to,
is just only for Humans, and not for computers.

A Use Case for a SIAP (SSAP, etc) ?
Here is mine, which I think is a quite typical usage of the 
SIAP/metadata tree concept:

a user posts SIAP requests to MULTIPLE (multi-wavelength, multi-epoch, 
etc) data centers;
all answers get merged and end up displayed in ONE and the same 
metadata tree
structured according to user's defined criteria, for easy browsing.


It is going to be much easier, for the tool that assembles all the SIAP 
answers
into a metadata tree, to see one and the same structure, no matter 
which data center
originated it.

For this reason, my vote goes for a FLAT, but structured anyway, SIAP 
answer, a la CDS,
and not for a data-provider specific model.

Tony wrote:

> Please just choose the best one and use that - if you really must, 
> post a
> pointer in the other group but ask people not to reply to that.

... hence, I'm posting only to the DAL.

Alberto