comments

[Andrew Lawrence]

I generally endorse Tony's comments. I think we need to aim at defining
a minimum standard.

(1) I strongly agree that we must keep the VO an enabling infrastructure
rather than an actual structure. Getting the right approach to the
Registry is a key step in getting the philosophy right. We shouldn't be
over prescriptive. It should be possible to have multiple Registries.
Registries should not require a supervising authority. A Registry should
be a service somebody can offer competitively, just like offering data
search services  etc.

(2) On the other hand, we want as much as possible of the software we
develop in the various VO projects to be inter-operable. 

(3) Each VO project should be free to use its own choice of
implementation technology, consistent with the interoperability
principle, and also free to make design choices, such as whether their
registry is fine grained or coarse grained. (At this stage we probably
want to positively encourage a diversity of choices, for technical
experimentation.)

The conclusion is that the IVOA forum should aim at answering the
question "what is the MINIMUM set of agreed standards that we should
agree on" ? I think some of the US-VO resource data document is relevant
to this aim, and some goes beyond it. Likewise in AstroGrid we are
starting to make some specific technology choices that we should not
necessarily force on others.

I am aware that all the above is rather vague and woofly. I will try to
think through what it means in more concrete terms. As soon as I get
through andoher eight classes and another six committees.

   andy


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Andy Lawrence                       e-mail      al at roe.ac.uk
Edinburgh Institute for Astronomy   Direct      (UK)-(0)131-668-8346
University of Edinburgh             ROE switch  (UK)-(0)131-668-8100
Royal Observatory Edinburgh         Liz Gibson  (UK)-(0)131-668-8356
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