1. GrADS-DODS Server An open-source tool for distributed data access and analysis Joe Wielgosz, Brian Doty, Jennifer Adams COLA/IGES - Calverton, MD http://www.iges.org/grads/gds OPeNDAP Working Conference - March 19, 2003 <dataset name = "test” file = "testdata/little_endian.ctl“>...

2. GrADS-DODS ServerJoe Wielgosz - joew@cola.iges.orghttp://www.iges.org/grads/gds Make GrADS-readable datasets - both gridded and in-situ - accessible across the network, to a diverse range of clients What the GDS can do Perform server-side analysis and comparisons against other distributed datasets serversclients and more... web browser LAS GDS OPeNDAP server GDS comparison data GRIB HDF4 netCDF BUFR Unidata IDV ncBrowse GrADS Ferret Matlab IDL OPeNDAP binary GrADS Java servlet

3. GrADS-DODS ServerJoe Wielgosz - joew@cola.iges.orghttp://www.iges.org/grads/gds What's new since 1.1 New data type support Station data - GrADS format and BUFR Remote OPeNDAP data Subsampling ("striding") for gridded data Core code refactored Anagram - generic data server framework Swappable, reusable modules Designed for efficiency - streaming I/O XML-based configuration, with more flexibility in: Dataset loading Logging Security Resource management Improved web interface Custom links to help, home, dataset info URL-based administration interface Scales better to 1000's of datasets Organizes data catalog into directories Faster startup and smarter caching

4. GrADS-DODS ServerJoe Wielgosz - joew@cola.iges.orghttp://www.iges.org/grads/gds Stable and fast COLA public GDS currently handling >600k hits/month Administrator-friendly Complete online documentation: http://www.iges.org/grads/gds/doc <dataset name="test" file="testdata/big_endian.ctl" format="ctl" /> <log mode="rotate" frequency="monthly" file="log/gds.log" level="info" /> Install in minutes (really!) No root privileges needed Cross-platform Java and ANSI C Easy to configure Edit one (simple) XML file, and make updates on-the-fly Secure Restrict dataset access & resource usage by IP address And more... Automatic scans for new datasets Detailed logging Graceful handling of heavy loads Easily integrated with Apache...

5. GrADS-DODS ServerJoe Wielgosz - joew@cola.iges.orghttp://www.iges.org/grads/gds In use, well-received Positive response from: COLA scientists GrADS user community - research, corporate, hobbyists NOAA/CIRES CDC (earliest adopters outside COLA) Some public GDS servers: (google on "grads dods server") COLA Public Data Server: cola8.iges.org:9191 (soon to be wxdata.org) COLA Monsoon Data Server: monsoondata.org NOAA/CIRES CDC: www.cdc.noaa.gov/dods FNMOC / GODAE: usgodae.org NCEP: nomad2.ncep.noaa.gov NASA / GSWP: voda.gsfc.nasa.gov:9090 NASA / NSIPP:beta.gsfc.nasa.gov:9090 plus activity at centers in France, Britain (BADC), and Japan...

6. GrADS-DODS ServerJoe Wielgosz - joew@cola.iges.orghttp://www.iges.org/grads/gds What to expect Continuing refinements to existing code - uncovering bugs (some suspected to still exist) - improving documentation where needed - addressing usability issues Station data support - Finishing up BUFR I/O interface in GrADS - Adding daily station reports to COLA public server - Releasing station-data-enabled GrADS client - Working on interoperability with other archives and clients Under consideration: - built-in metric collection - catalog server - login-based authentication - near-line data support - listening for ideas

7. GrADS-DODS ServerJoe Wielgosz - joew@cola.iges.orghttp://www.iges.org/grads/gds COLA thoughts on OPeNDAP "DODS" vs "OPeNDAP" With apologies, waiting for 4.0 - don't want to confuse user community New protocol I see DAP 4.0 as a chance to reduce complexity and increase robustness We all have limited development resources - keep size of protocol proportional Interoperability means common ground, not sum of all features Anagram / Server-side Java Java is an ideal server platform - stable, cross-platform, easy to code Consider Anagram framework + Java-DODS as servlet counterpart to DAP C++ CGI framework? Slot in custom functionality to a standard core - good for gateways, access control / resource limits, web services, etc. Analysis protocol Increasing usage at COLA - perceived by scientists as extremely valuable Time to think about interoperability? Complex issues involved Modeler's needs Grid / ESG II Authentication important for collaborative projects Can OPeNDAP provide a way for small shops to get Grid-enabled?