Experiences with the Application of Services Oriented Approaches to the Federation of Heterogeneous Geologic Data Resources

The federation of databases is not a new endeavor. Great strides have been made e.g. in the health and astrophysics communities. Reviews of those successes indicate that they have been able to leverage off key cross-community core concepts. In its simplest implementation, a federation of databases with identical base schemas that can be extended to address individual efforts, is relatively easy to accomplish. Efforts of groups like the Open Geospatial Consortium have shown methods to geospatially relate data between different sources. We present here a summary of CHRONOS's (http://www.chronos.org) experience with highly heterogeneous data. Our experience with the federation of very diverse databases shows that the wide variety of encoding options for items like locality, time scale, taxon ID, and other key parameters makes it difficult to effectively join data across them. However, the response to this is not to develop one large, monolithic database, which will suffer growth pains due to social, national, and operational issues, but rather to systematically develop the architecture that will enable cross-resource (database, repository, tool, interface) interaction. CHRONOS has accomplished the major hurdle of federating small IT database efforts with service-oriented and XML-based approaches. The application of easy-to-use procedures that allow groups of all sizes to implement and experiment with searches across various databases and to use externally created tools is vital. We are sharing with the geoinformatics community the difficulties with application frameworks, user authentication, standards compliance, and data storage encountered in setting up web sites and portals for various science initiatives (e.g., ANDRILL, EARTHTIME). The ability to incorporate CHRONOS data, services, and tools into the existing framework of a group is crucial to the development of a model that supports and extends the vitality of the small- to medium-sized research effort that is essential for a vibrant scientific community. This presentation will directly address issues of portal development related to JSR-168 and other portal API's as well as issues related to both federated and local directory-based authentication. The application of service-oriented architecture in connection with ReST-based approaches is vital to facilitate service use by experienced and less experienced information technology groups. Application of these services with XML- based schemas allows for the connection to third party tools such a GIS-based tools and software designed to perform a specific scientific analysis. The connection of all these capabilities into a combined framework based on the standard XHTML Document object model and CSS 2.0 standards used in traditional web development will be demonstrated. CHRONOS also utilizes newer client techniques such as AJAX and cross- domain scripting along with traditional server-side database, application, and web servers. The combination of the various components of this architecture creates an environment based on open and free standards that allows for the discovery, retrieval, and integration of tools and data.