# Presentation: 215431

## VOregistry and VOgrid:Tools For An Integrated Heliophysics Data Environment

- Tom Narock1,2   Jan Merka1,2   Adam Szabo2
*1.) University of Maryland, Baltimore County (GEST)*
*2.) NASA Goddard - Heliospheric Physics Lab*

## Two independent but related projects for extending the heliophysics data environment 

http://vogrid.gsfc.nasa.gov

http://voregistry.gsfc.nasa.gov 

- _http://vogrid.gsfc.nasa.gov_
- _http://voregistry.gsfc.nasa.gov_

## VOregistry

-  VxOs implement added-value services to varying degrees
-  Groups independent of VxOs (CDAWeb) implement web services
-  A registry is needed to manage the ever increasing capabilities of the heliophysics data environment

## VOregistry

-  We are implementing a semantically enabled registry named VOregistry (web interface and API)
- Searches are carried out via a space physics ontology
- Provides more efficient and flexible searching

## VOregistry

- Keyword or categorized searches are difficult to implement with web services
- Additionally, they are often binary (match or no match)
- Ontologies allow for partial and associated matches

## VOregistry

- Initial ontology based on data model from international collaboration
- We converted the SPASE XML schema into an OWL-DL ontology

## Searches are conducted by selecting requested inputs and outputs from ontology terms 

- Searches are conducted by selecting requested inputs and outputs from ontology terms

- Displays selected inputs/outputs as well as ontology they came from - software allows for searches over multiple ontologies - can add more ontologies as needed

- Ontologies allow for new types of matches

## We would like to input a specific spatial region

- We would like to get back Magnetic Field measurements

- VHO is an exact match of these inputs and outputs

## Again, we ask for a specific spatial region

- We would like to get back any data available in this region

- Again VHO is found but flagged as having more specific output, i.e. does  not deal with all possible measurement types

- Ontology allows for encoding of space physics knowledge and relationships

## Ontology allows for partial matches

Scientific knowledge is captured in the registry

- Scientific knowledge is captured in the registry

## VOregistry

- Provides access to service description files so that they can be executed

- If available, registry can take you directly to service web site

## VOregistry

-  Applications like CoSEC allow chaining of services - VOregistry can narrow down choices
-  Can work with VxOs to answer queries

- VxO

## VOgrid

- An effort to use Grid technologies (Globus Toolkit) to house VxO services and share computational resources and libraries
- Grid services (WSRF) can have advantages over traditional web services in VxO environment

## VOgrid

-  Testbed for deploying a grid environment and implementing services
- Will examine the benefits of grids and test interactions with VxOs

- 3 Desktop computers of varying architecture

- Interface to community

## VOgrid

-  Benefits of Grid services (1)

- Access to computational power and load balancing options

- Image from: www.amd.com

## VOgrid

- Benefits of Grid services (2)

- Mass storage - ability to store files across grid and/or check if they exist prior to accessing the network

- Image from: www.dell.com

- SPDF could be an ideal location for grid environment

## VOgrid

-  Appears to community as a single entity
-  One machine housing multiple services

- Benefits of Grid services (3)

## VOgrid

-  Stateful Web Services - can maintain persistent values or access previous executions

- Benefits of Grid services (4)

- Access to previously executed service results can lead to new services which aggregate results

## VOgrid

-  Simplicity of service creation can lead to more services
- Community will have a place to house services
- Will contain common libraries and needed infrastructure
- No need to develop full web service just contribute analysis code

- Benefits of Grid services (5)

## VOregistry and VOgrid	

-  The complete picture

- Users

- VOregistry

- VOgrid

- Other (non Grid) web services

- VOgrid gateway