Though geographic data has never been more plentiful...much of it remains
difficult to find and access.
The Geography Network...is based on the concept of a geospatial data
Create a central repository for publishing and browsing metadata over the
Distribute data through an ArcIMS map service.
Build Your Own Geography Network
The Internet has enormous potential for publishing and distributing geographic information. For most organizations, the greatest cost of developing a geographic information system (GIS) is the acquisition and maintenance of data. Though geographic data has never been more plentiful than it is today, much of it remains difficult to find and access in formats that can be easily used. The Internet is helping solve this problem by offering a platform for data sharing and discovery that is becoming pervasive.
By leveraging the power of the Internet, the Geography NetworkSM is providing access to geographic information in open formats that can support users of all types. The technology used to build the Geography Network is now available for other organizations that would like to build a geography network of their own. Here's how…
Geography Network Overview
Building a Geography Network with ArcIMS
Geography Network Overview
The Geography Network is a framework for sharing and discovering GIS data and services on the Internet. It is based on the concept of a geospatial data clearinghouse developed by government organizations around the world. It provides a mechanism for GIS users to publish and access GIS data and services worldwide. The Geography Network consists of three parts
- Web Site (www.geographynetwork.com): The Web site serves as a clearinghouse to discover and access geographic content registered in the Geography Network. The site is built around a catalog of the Geography Network content and provides tools to discover and access this content. This catalog is powered by the ArcIMS Metadata Server. The ArcIMS Metadata Server supports the publication and retrieval of metadata (i.e., reference information) about content available through the Geography Network.
- User Communities: These are groups of organizations or individuals that use Geography Network content to support their professional or personal interests. User communities are often organized around a geographic area of interest (e.g., Texas) or an industry area of interest (e.g., natural resources). These communities may access Geography Network content in different ways (e.g., directly through GIS tools or indirectly through custom Web applications).
- Content Providers: Content providers are government and commercial organizations that provide access to thousands of content elements including maps, data, services, and applications. The content is maintained in a distributed environment so that it may typically be accessed directly from the source.
Building a Geography Network with ArcIMS
The Geography Network framework can be leveraged by many types of organizations, both government and commercial, to collect and publish geographic content for its user community. For example, a state-level government agency may want to provide a clearinghouse for geographic content available in its state. An international health organization may wish to develop a clearinghouse for health-related geographic content around the world. These clearinghouses would each represent a geography network, comprised of organizations that support a common user community.
One tool that may be used to support the development of a geography network is ESRI's ArcIMS software. ArcIMS is ESRI's solution for distributing mapping and GIS data and services on the Web. One of the most significant features included in ArcIMS is the ability to create a central repository for publishing and browsing metadata over the Internet. Metadata can be authored using ESRI's ArcGIS ArcCatalog application, published to a metadata server, and then quickly searched by others. Along with ArcIMS software's metadata services, users also receive the Metadata Explorer, which is a JavaServer Pages (JSP) application that can be used to build a customized, browser-based means of searching for data. Users can use ArcIMS map services to publish data for immediate access. In these ways, ArcIMS provides an out-of-the-box toolkit for building a geography network.
Below is a summary of the typical steps needed to build a geography network using ArcIMS. Documents at the bottom of this page include additional information.
Prepare Data to Publish: A geography network typically includes a variety of geographic data sources that may be accessed as downloadable data or streaming data through map services. To distribute data through an ArcIMS map service, the first step is to prepare the data for publishing. This may include development of digital data from other sources, conversion of data to publishable formats (e.g., shapefile, ArcSDE, TIF, MrSID), or the processing of data to optimize performance.
- Configure ArcIMS System: Data publishers need to configure an Internet mapping system to publish content and support user requests. The size of this system can vary significantly, depending on the anticipated usage, but the system will always need to include hardware, software, data, network, and staff components. The system must be configured to support the anticipated levels of usage, required levels of availability, and planned types of applications.
- Author and Publish Map Services: After the ArcIMS system is configured, the data provider will need to author and publish map services. This step will include defining the content of the map services (i.e., which data layers to display and how), authoring the services using ArcIMS Author, and testing the performance of the services in the intended user environment.
- Assemble and Publish Metadata: Once the map services are authored, or other content is prepared for publishing, the next step is to assemble and publish the metadata for the content. A geography network may include many types of content such as static map images, downloadable data, or geographic services. Metadata must be assembled for each piece of content using tools such as ArcCatalog, then published using the ArcIMS Metadata Server.
- Customize and Deploy Web Site: When the content and metadata have been published, the Web site can be built to provide access to this content. A geography network Web site will typically enable users to search or browse for desired content, preview metadata about the content, and access the content as appropriate. The Web site may include custom applications to provide specific functionality that is desirable for the content (e.g., a browser-based mapping application to view multiple map services).
These documents offer additional information on building a geography network.
If you have other questions, please contact us.