GEOSS Common Infrastructure: A practical tour

Doug Nebert

U.S. Geological Survey

September 2008

GEOSS Common Infrastructure (GCI)

Common set of core services that promote the integration of GEO and GEOSS as a functional

System-of-Systems

Includes:– Component and Service Registry– Standards and Interoperability Registry– User Requirements Registry (in development)– Best Practices Wiki – GEO Web Portals– GEOSS Clearinghouse

GEOSS Common Infrastructure provides

…a place where GEOSS-affiliated resources can be identified, found, and applied directly, or in support of one or more Societal Benefit Areas.

GEOSS Common Infrastructure value

• Affiliation: Registration with GEOSS defines membership or participation in GEOSS

• Discovery: Registration of systems and services allows them to be discovered (searched and browsed) through GEOSS

• Integrity: The association of services with known standards and practices facilitates integration and re-use of registered services, related data, and applications

• Destination: GEOSS common infrastructure provides a single focus for GEO-related resources: services, standards, best practices, user requirements

User Context for GEOSS

• Publisher point of view – a GEO member or participating organization has a resource of interest to share with GEOSS

• User point of view – a member of the public is interested in finding information and services related to earth observation (ocean, land, atmosphere) data

Publisher’s viewpoint1. An individual publisher goes to the GEO Web Portal and is then

linked to the GEOSS registration system. 2. Information about their earth observation initiative/system is

entered as metadata into an online web form, as is the URL to the registrant’s website. While being entered, the System is classified by the Societal Benefit Areas (SBA) it primarily supports, its type (activities), and the timeframe of information availability.

3. The GEO Secretariat validates the registration based on the status of the registering individual.

4. For each System, one or more service interfaces may be registered. Each service is described and linked to a GEOSS-listed standard or special arrangement (community practice). If a standard or special arrangement is not present, the user is allowed to nominate one or more through a web form in common with in the Standards and Interoperability Register.

5. Once entered, the system and service information can be discovered through the GEO Web Portal

User’s viewpoint

1. User is interested in finding information related to EO as registered with GEOSS

2. User searches for data, documents, and related services through one of several search form on the GEO Web Portal. This allows search on text, resource type, location, temporal coverage, and some classifications.

3. Titles, descriptions, and links are returned from the search engine.4. The user clicks on the result links to obtain more detailed descriptions

(metadata) or connects directly to the resource being described. Some types of results can be visualized or processed using ‘helper’ software already installed on their desktop computers or through linked client applications provided by the Web Portal. Results may be links to services, data, documents, capacity building materials, best practices, standards, etc.

5. Integrators may access GEOSS by embedding catalog search clients into their decision-support software to provide direct search of GEOSS in lieu of the GEO Web Portal. Thus, the end-user may remain in their preferred application environment and perform search on GEOSS and apply/integrate the results.

GEOSSComponent and Service Registry

GEOSSStandards andInteroperability

Registry

references

links to

User

accesses

accessesservice

descriptions

searches

GEOSS Common Infrastructure

GEONETCast

ServicesData and Service

Catalogues

Websites/Portals

(Components)

Registered components and services

Main GEOWeb Site

links to

catalogues all

Catalogqueryclients

accessesregistry items

links to

Registrationclients

Registryqueryclients

Clearinghouse provides means to connect to registered services viametadata

Web browser

UnregisteredCommunity Resources

Web pagesDocuments

RSS

Best PracticesWiki

User RequirementsRegistry

Applications

references

GEOSSClearinghouse

GEOSSClearinghouse

GEOSSClearinghouse

GEO Web PortalGEO Web PortalGEO Web PortalRegistries

GEOSS common interactions

GEOSSComponent,

Service registry

Standards,Special

ArrangementsRegistries

references

GEO Web Portal orclient application

searches

Offerors

contribute

CommunityResourcesaccesses

GEOSSClearinghouse

Catalogues

Services

User

accesses

get catalogueservices

accesses

searches

invokes

1

2

34

56

7

8

Component and Service Registry

• Allows registration of a Systems (component) and related multiple services or URLs that provide access to information

• Each System is related to one or more Societal Benefit Areas (SBAs)

• Each Service entry can be associated with one or more Standards or Special Arrangements in the Standards and Interoperability Registry

Standards and Interoperability Registry

• A collection of standards and community practices that are nominated through the registration process by GEO individuals

• Nominations are processed by the Standards and Interoperability Forum (SIF) and are classified as:– Standards: if maintained by a standards

development organization, or– Special Arrangements: ad hoc community

practices, methods, techniques• Standards and Special Arrangements are established

as a pick-list for use elsewhere in GEOSS and include IDs, names, descriptions, and links to the owning authority

GEOSS Clearinghouse

• An all-of-GEOSS search facility that provides API access to metadata on all services and systems from the Component and Service Registry

• Registered catalogue services, in turn, are inspected and their inventory of records is also made searchable

• Metadata may describe systems, services, data, documents, or more specific file types

• Access to Clearinghouse is provided through a search API based on OGC CSW 2.0.2 and is implemented by GEO Web Portals and other client applications

Best Practices Wiki

• A place to post best practices in a semi-structured document form that are intended to be shared across GEOSS

• BP may reference common techniques for a scientific area of study, for IT deployment, or for domain and cross-domain applications

• Wiki entries may link to registered service instances, standards, or other document types that are relevant to the practice

GEO Web Portals

• Supports client access to catalogs, map services, and data services through standards-based interfaces

• Provides user interface for search on the GEOSS Registries

• Low/minimal cost of re-deployment, readily customizable and extensible

• Includes community management tools and portlets

• Content management capabilities including teaching materials, documents

• Ability to integrate and visualize disparate resources and services through Web Map Service and KML/RSS viewers

• Place to reference (link to) or host (embed portlets for) end-user support applications

User Requirements Registry

• Stores requirements by generalized user types that identify observables and their properties (e.g. values, quality, resolution, frequency, units of measure) with respect to a domain of application

• Matching of requirements to service offers can be made in the future as a common vocabulary of observables is developed for GEOSS to:– Identify coverage and popularity of observations,

and– Identify gaps in coverage of observations

Publishing to GEOSS

Registration process for publication of systems, services and data.

Prerequisites

• Individual/organization has identified a system (collection of imagery, base data, sensor data) that it wishes to contribute to GEOSS

• Contributor understands the data sharing principles promoted in the 10-year plan reference document: “GEOSS provides a mechanism through which partial or full

data sharing can be negotiated and a technical process by which it can be achieved.” Sec 3.1

• Ideally, the publisher can identify or develop Web service interfaces or data access protocols that can be described and accessed over the Internet in standard ways

• GEO Web Portals have a link to register

RegisterSearchRegistry

StandardsRegistry

http://geossregistries.info/geosspub/http://geossregistries.info/geosspub/

Using GEOSS

Discovery and use process for registered systems, services and data.

Prerequisites

• Interest in finding registered systems (components), services, and the data that they provide access to

• Ability to search and browse using a Web Browser to access one of the GEO Web Portals, linked from http://www.earthobservations.org

• For advanced use of data and services, user may need additional specialized client software, e.g. image manipulation software, 3-D viewers, GIS, analytical tools

GEO Web Portals

GEO-wide Web Portal provide access to GEOSS resources based on common requirements.

Web Portals can be re-deployed for communities, countries, or SBAs but retain access to common architecture (Registries, Clearinghouse, Component Services).

Steps to using GEOSS

1. Select one of the GEO Web Portals. There are three that have similar functionality – find the one that suits you

2. Use the various search facilities in the GEO Web Portals to locate information:• Review the RSS feeds, earth observation, and SBA-

specific information for an introduction • Search the Component and Service Registry if you are

interested in finding systems and their related SBAs and services

• Search the GEOSS Clearinghouse if you are interested in locating services, data, and other documents registered in community catalogues

GEOSS Clearinghouse SearchGEOSS Clearinghouse Search

Directions and Issues

• Registration system is ‘service-oriented’ although data are accessed through services or protocols

• Need to identify additional resource types to register for explicit connections (i.e. documents, models, applications, presentations, training materials) that could be registered and then made available through search

• User Requirements Registry is still in development, needs to be populated with existing works and linked to the other registries

• Need to clean-up and clarify registrations and the linkages (URLs) that could be exploited by helper software (browsers, Google Earth, image/GIS, etc)

Where to go to experiment with GEOSS

• GEO Website:– http://www.earthobservations.org

• GEO Web Portals:– http://www.geoportal.org– http://www.geowebportal.org– http://keel.esri.com/Portal

• GEOSS Registries Links– http://geossregistries.info