Elements of the Internet Computing Model for Geoprocessing

The Internet Computing Model for Geoprocessing consists of the core technologies and standards for implementing distributed geoprocessing, which are woven into mainstream IT as an integral part of the global information economy.

The key elements of the model are defined below:

• Digital Earth – A virtual model of the earth, comprised of the total set of geospatial holdings on the Net. These holdings are bound together as a coherent, consistent and universal earth model by virtue of common standards for geospatial data and geoprocessing. The Digital Earth is part of the Global Information Infrastructure.
• Geospatial Components – The plug-and-play building blocks for ubiquitous geoprocessing. Multipurpose components with standardized, easily composed interfaces and well-defined behaviors.
• Geospatial Agents – Active (mobile on the Net), autonomous applications that have the means to search, discover, access, interact and assimilate geo-intelligence from remote services (e.g. geospatial servers and appliances). They are comprised of one or more geospatial components.
• Net-enabled Geospatial Applications – Standalone geospatial applications that access other Net-based resources, including net-source geospatial servers, data, applets, agents and appliances. They are comprised of one or more geospatial components.
• Net-source Geospatial Servers – Net-enabled servers that are capable of serving subsets of their geospatial data and/or geospatial applet holdings to remote clients that are requesting service. The clients may be geospatial applications, applets, appliances or other geospatial servers. They are comprised of one or more geospatial components.
• Net-source Geospatial Data – Geospatial data that are packaged and transported over the Net.
• Net-source Geospatial Applets – Plug-in geoprocessing applications that can operate through a Web browser. Comprised of one or more geospatial components. Geospatial applets can be easily transported over the Net.
• Net-source Geospatial Appliances – Spatially-enabled devices that are accessible on the Net. They are comprised of one or more geospatial components.
• Geospatial-hybrids – Any applications, servers, data, applets, agents and appliances that make use of geospatial data and embedded geospatial components, but serve primarily a non-geospatial oriented purpose.
• The Net – The Global Network Infrastructure that supports distributed communications and computing, including the physical network, network computers and core network services. This infrastructure includes Java Platform and Jini; the core software technologies for enabling distributed geoprocessing.

The "GeoJava" Internet Computing Model

This section briefly addresses how the Internet Computing Model for Geoprocessing can be implemented with Java to support ubiquitous geospatial data and geoprocessing.

The GeoJava Internet Computing Model is built upon the Global Network Infrastructure and provides an extended service infrastructure consisting of core geoprocessing services and application support services. This service infrastructure includes Java Platform and Jini, the foundation software technologies that enable distributed GeoJava applications and services.

The GeoJava Internet Computing Model supports a variety of GeoJava-based elements that can be transported over the Net, namely: geospatial data in the form of Java Data Containers; simple geospatial components (objects) in the form of JavaBeans; intelligent geospatial components in the form of Java Agents; geospatial applications in the form of Java Applets; and hybrid versions of these four types of elements, where geospatial data and software are integrated, packaged and transported with non-geospatial data and software.

Within "service consumer" environments that implement the GeoJava Internet Computing Model, service consumers can invoke GeoJava applications on local workstations, via Web browsers with Java Applets, or through thick-client or thin-client Java Applications. Local service consumers can also gain access to Java Applications and Java Servlets on local proxy servers. In more complex enterprise settings, service consumers may also invoke extended enterprise functionality over intranets and extranets. These capabilities are implemented through component-based Enterprise JavaBeans and through hybrid Java Applications and Java Servlets, or they may exploit mobile computing services consisting of Java Applets, Java Data Containers or Java Agents.

"Service provider" environments that implement the GeoJava Internet Computing Model can offer a variety of net-source GeoJava services. These include: geospatial appliances that run Java Applications, Java Agents and/or Java Beans; geospatial servers that run Java Servlets and Java Applications, which access and serve up geospatial and/or hybrid data (e.g. "Digital Earth"), applets or beans; and specialized geospatial agencies that serve up intelligent Java Agents.

In summary, the GeoJava Internet Computing Model allows any geoprocessing or hybrid application in any service consumer or service provider environment to access any net-source GeoJava servers, data, applets, agents or appliances.