• Implemented “Semantic” WFS FE, CSW, and other components for use in processing geospatial queries which leverage Knowledge Base connections.
Semantic Service-oriented Architecture
Client
Broker Trader
Servers
Fin d
Pro vi
si on
Pu blis
h
O rde
r Bind
Figure 19 - Four roles and their relationships comprising a basic SSOA Semantic Service-oriented Architecture.
Applications of OGC services are generally focused around the concept of a service- oriented architecture, in which service consumers bind dynamically to useful instances of
standard services through a process of service discovery. This process is usually facilitated through a trading component, which may be represented by an OGC catalog.
Semantic interoperability across the Knowledge Base introduces a new requirement, since merely discovering and binding to useful geospatial information resources may not
be sufficient for effectively exploiting them. A broker function is often required, which is able to perform semantic translation from the knowledge context in which the resource
was created, into the context of the GEOINT user who may be widely separated in both a physical and intellectual sense from that resource. This broker function may be
implemented as a catalog ordering operation andor through schema translation performed by a Web Feature Server.
Multiple ontologies
An essential aspect of the GEOINT Knowledge Base, as a distributed system serving multiple information communities, is the use of multiple ontologies or distinct
representations of bodies of knowledge. There is no single harmonized and integrated ontology representing all human knowledge of the world as yet. The Knowledge Base
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must leverage OGC concepts, services and encodings to manage multiple ontologies which are distinct yet spatially, temporally, and conceptually overlapping.
GeoIntel Problem Domain
Ontology Base Geospatial Ontology
e.g. filter encoding Aero Feature
Ontologies AIXM, DAFIF
OGC Upper Ontology
e.g. Feature
Other Base Ontologies e.g. measurements Other Upper Ontologies
Figure 20 - Schematic representation of multiple ontologies used to perform a geospatial semantic cross-domain query.
Just as the communities they represent remain separate but overlapping, so these ontologies are expected to maintain separate identities but be linked e.g. via subsumption
or mapping into a knowledge base either physical or virtual capable of providing answers to cross-domain queries.
5.6 Geo-Decision Support Services GeoDSS for NSG
5.6.1 Integrated information environment and OWS portal architecture
Multiple levels of service will be available to answer the GEOINT portion of customer information needs. NSG data holdings will be managed dynamically in a manner to
facilitate content reuse and customization of GEOINT. Customers will have universal access to these data holdings at the NSG level through a web-enabled standardized
enterprise portal, providing a one- stop point of access. GEOINT portal operations will be characterized by use of:
• Data standards, metadata tagging, and data at multiple levels of security and releasability,
• Tools that support data discovery and data mining, • Shared, common services designed to operate as part of a larger national security
community repository, • Interfaces to other NSG, DoD, IC, commercial, and academic portals, and
• Enhanced bandwidth.
• An Integrated Information Environment. Information management and sharing across
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the NSG are disconnected among intelligence disciplines and national, theater, and tactical levels, and do not provide horizontal integration. By 2015, the nation must have
an integrated information environment, requiring comprehensive capabilities for information generation and management. Initiatives critical to providing a fully
integrated and agile approach for sharing collection and analytic resources and exchanging GEOINT across the enterprise must be given programmatic priority. In
addition to information generation and information management capabilities, a horizontally integrated information environment will require standards,
interoperability, and data sharing.
5.6.1.1 Applicable OGC specifications and developments
• Geospatial Portal Reference Architecture Discussion Paper • OpenGIS® Catalog Service Implementation Specification CSW
and complementary CSW profiles: -
ISO19115ISO19119 Application Profile for CSW -
ebRIM ISOTS 15000-3 Application Profile of CSW -
Earth Observation Application Profile for CSW • Information access standards
- Web Feature Service Implementation Specification
- Web Coverage Service Implementation Specification
- Web Mapping Service Implementation Specification
- Simple Feature Access Implementation Specification
- Feature Portrayal Service Discussion Paper
- Sensor Alert Service Discussion Paper
- Sensor Observation Service Discussion Paper
- Sensor Planning Service Discussion Paper
- Style Management Services Discussion Paper
- Symbology Encoding Implementation Specification
- Styled Layer Descriptor profile of the Web Map Service Implementation
Specification -
Feature Styling OWS-4 Interoperability Program Report
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- Multilingual Open Web Services OWS-4 Interoperability Program Report
• Network Infrastructure and Security -
Geospatial Digital Rights Management Reference Model GeoDRM RM Discussion Paper
- GeoDRM Thread Activity OWS-3 Discussion Paper
- Trusted Geoservices Model OWS-4 Interoperability Program Report
- GeoDRM Engineering Viewpoint OWS-4 Interoperability Program Report
- OGC Web Services SOAP Experiment Discussion Paper
- OGC Web Services UDDI Experiment Discussion Paper
- Gazetteer Service - Application Profile of the Web Feature Service Best
Practices -
Web Coordinate Transformation Service Discussion Paper -
Web Processing Service Discussion Paper
5.6.1.2 Discussion of applying OGC specifications to meet NGA objectives
The concept of a single portal is one that is falling out of favor as the industry’s experience with deploying Web services in large organizations, and even more so in
multi-organization contexts, evolves. We are moving towards envisioning systems of systems, or dynamic information sharing architectures that allow individual agencies and
departments to leave and join information networks as required by organizational and operational needs. That being said, the flexibility of a Web services-based architecture,
and OGC’s expression of that architecture in its geospatial services, is well equipped to evolve along these lines.
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