Summary: features for VOEvent v2.0

[Matthew Graham]

Hi Rob,

I think that this is the clearest summary of what is in VOEvent 2.0 that I've yet seen.

	Cheers,

	Matthew

On Apr 9, 2010, at 4:28 PM, Rob Seaman wrote:

>> How is a v1.1 packet compliant with a prose specification for a later version? Every entity in the packet retains its original structure in the later version?
> 
> <SimpleTimeSeries> and/or <SimpleTables> are new elements.  They will be optional.
> 
> Ephemerides and orbital elements are conforming STC - the intent is, if anything, to simplify the implementation of <ObsDataLocation> in the v2.0 VOEvent schema.  (The floor is open for discussion regarding the details.)
> 
> The <Reference> and <Param> typing will be additional (but optional) attributes and/or looser constraints on the values of those attributes.
> 
> <Params> are currently empty elements - permitting them to have values (should this be the consensus) will not deprecate the currently empty expressions.
> 
> Any change to <Inferences> under <Why> (for v2.0, anyway) will be restricted to adding attributes and/or elements or loosening previous restrictions.  Any such changes will be modest in scope.
> 
> Finally, I do not believe that we need to retain compliance with packets that nobody ever has or ever will create.  Aside from simplifying our usage of STC, all changes will be relaxing prior restrictions.  In some Platonic world, requiring more stringent limitations on <ObsDataLocation> (however achieved) would be deemed to blast backwards compatibility into smithereens.  This is not that world.
> 
> I presume that projects parsing packets using Eli Whitney era technology do not care about the change to the explicit version in the packet header.
> 
> Rob
>