RE: GALEON OGCnetwork

• To: <rlake@xxxxxxxxxxxxx>, <Ben@xxxxxxxxxxxxxxxx>, <galeon@xxxxxxxxxxxxxxxx>
• Subject: RE: GALEON OGCnetwork
• From: <Simon.Cox@xxxxxxxx>
• Date: Mon, 10 Apr 2006 10:41:49 +0800

Comments on two aspects of this:

1. Metadata
The GML 3.1 and earlier treatment of metadata - using the gml:metaDataProperty 
element - turned out to be rather too onerous/tricky for the developers of 
application schemata where they wanted to use an existing metadata schema, 
which is not derived from GML.
The GML pattern required a GML "wrapper" for eveything, in addition to the 
metaDataProperty element.  After going around the issue a few times, the GML 3.2/ISO 19136 approach 
was to instead add a "flag" that may be shown on any property element to indicate that it 
is metadata.
So I would not recomment designing anything now on the basis of the GML 3.1 
patterns since they will be superseded in GML 3.2.

2. coverage "domain".
I have discussed the matter of generalizing the coverage domain with the ISO 
19123 editors and others.  The story I got was that the ISO Coverage model is 
specifically *not* a general purpose map.
It is specifically a map with a spatio-temporal domain, because the intention 
is to target spatio-temporal processes and processing.  Of course everyone 
recognises that Coverages defined in this way are simply special cases of 
general maps.
So the questions I thinka re raised by this discussion are (i) is the GML implementation of 
Coverage canonical? (ii) should WCS be modelled as a special case of a "map" or 
"function" service?

Simon