Hello all,
We have submittted the progerss report from our group to the GALEON wiki. The
somewhat bulky summary is reproduced below.
http://capita.wustl.edu/capita/researchareas/GALEON/Reports/060206/060206_GALEON_IE_DataFed.htm
DataFed - GALEON IE Summary
This second progress report contains the findings on interoperability between the GALEON
WCS test servers and the DataFed <http://datafed.net/> WCS client and the development
of a DataFed WCS server. The first DataFed
report<http://capita.wustl.edu/capita/researchareas/GALEON/051128_GALEON_IE_Rept.htm>
on the GALEON wiki (Dec 5, 2005) contained the early IE results.
The DataFed <http://datafed.net/> WCS client can successfully access the WCS data sets from
the U. Florence
<http://athena.pin.unifi.it:8080/galeon/WCS-v1.0?REQUEST=GetCapabilities&VERSION=1.0.0&SERVICE=WCS>
and from the UNIDATA THREDDS WCS test servers. The spatial queries to both servers yield the
expected return as spatial grids. Within DataFed, the received WCS (NetCDF) data from both servers,
are easily transformed into data views and used in distributed web applications by chaining
appropriate web services.
As an experiment, we have created a WCS test server to serve a wide variety of
point, grid an image coverage data. Our goal was to evaluate the WCS protocol
for accessing coverages of different types arising from a variety Earth
observation and modeling systems. We are most encouraged by the possibilities
but recognize that considerable work is to be done on the extending the
describeCoverage schema to accommodate these coverage types and to augment the
returned data types (e.g. a Table) to accommodate these additional coverage
types. The discussion on the possible WCS extensions is given in a separate
report to the GALEON IE group. Due to the late completion of the DataFed WCS
server, it has not been tested for interoperability by remote clients.
Substantial hurdles are still ahead before we reach a 'snap'-like WCS
client-server interoperability including:
- the temporal aspects of the WCS queries needs more work both on server and
client side
- automatic (loosely coupled) registration of WCS services needs work (using
ncML-GML ?)
- geo-re-projection services (preferably web services) to handle the
homogenization of the mired projection used by the different data providers.
We recognize that many of the current inadequacies are being addressed in other
interoperability efforts and possibly by the continuation of this IE. We are
looking forward enhancing our interaction with the group as well as individuals
in this group while striving toward better interoperability of our data systems.
--
Professor of Mechanical Engineering, Director
CAPITA, Washington University
St. Louis, MO 63130
1 Brookings Drive, Box 1124
314 935 6099