1. 30 October 2008 IVOA Interoperability Meeting -- Baltimore T HE I NTERNATIONAL V IRTUAL O BSERVATORY ALLIANCE VOTable interface with Registry Joint Apps/DM/Registry – G. Greene Application Registry Clients NVO Discovery Portal Interfaces

2. 30 October 2008IVOA Interoperability Meeting -- Baltimore Motivation for App Registry Interface Early NVO Science projects demonstrated the usefulness of registry programmatic search interfaces –Query registry of centralized resources with filters on science qualifications to find common services of interest waveband, images, catalogs, etc. Programmatic interfaces were developed from the bottom up using fashionable web services (SOAP) –Application requirements created “SimpleResource” view of registry resources metadata Web Service quick uptake, quick growth in application client dependencies –Datascope, OpenSkyQuery, WESIX, VOClient, JAVA lib …

3. 30 October 2008IVOA Interoperability Meeting -- Baltimore Limitations to Interfaces Custom dependency on a specific registry – Pitfalls of non standard implementation – Server side WSDL changes resulted in breakage of client software Mirroring registry alleviated failover concerns yet demands resources to fully transition to operational support Non-standard formats for reference implementation produced short term solutions and eventually software refitting needed

4. 30 October 2008IVOA Interoperability Meeting -- Baltimore Standard Registry V1.0 Resource element definition *changed* to a composite hierarchical structure –Resources CAN represent collections which contain multiple different service capabilities (i.e. cone, sia, ssa, skynode, s*) –Service Capabilities may have multiple interfaces –Service Capabilities may have multiple versions VOResource schema and associated extension schemas include rich namespace management, serialization −Requires development of new software libraries Standard Registry Interface v1.0 Search based on SOAP protocol – Eliminates application dependency on single registry – SearchRequest container for VOResourceS – Exception case is the OAI harvesting

5. 30 October 2008IVOA Interoperability Meeting -- Baltimore NVO Data Discovery Portal Interoperable suite of Applications –Science use case oriented toward location and discovery of data through VO DAL services ( CONE, SIA, SSA, Skynode, etc.) –Absence of Software libraries for working with new Registry Interface services and VOResource data model Proposal for working with VOTable simplification of VOResource –Recognized this was NON-Standard yet active communication and collaboration with RWG –Defined a set of CORE registry fields that discovery applications required, allows for optional –XSLT technology identified for transformation of the VOResource data model into a defined ResourceVOTable

6. 30 October 2008IVOA Interoperability Meeting -- Baltimore Making Choices – Apps Requirements Applications requirements prioritized higher to achieve science goals –Move forward and provide psuedo solutions … and wait for the dust to settle on the RI standards evolution ?? VOTable – TAP registry interface on the horizon Require a resource service container that may be transferrable between web applications –user state for managing discovered services How to find the individual services with composite resources => optional return type –Rows of resources with multiple interfaces –Rows of interfaces with redundancy in resource Complexity with uniqueness

7. 30 October 2008IVOA Interoperability Meeting -- Baltimore Resource Container ResourceVOTable = Flat-Field * Resource Variable Length service interfaces –#delimiters Defined set of CORE service metadata elements applications require –e.g. title, ivorn, service type, accessURL Programmatic dependencies, software coupling is growing –would prefer non-proprietary standard solution before the client technology evolves XSL filtering for specific VO protocol capabilities to expand on interfaces

8. 30 October 2008IVOA Interoperability Meeting -- Baltimore Services Service endpoint viewable in parallel to the Registry Interface standard services … http://nvo.stsci.edu/vor10/riws.aspx NVO Registry Interface primary search criterion: –Keyword –simple predicate (e.g. title like ‘%chandra%’) –capability (aka Cone, SIA, SSA, …) –Wavelength Optional VOTable output handling