Objective

This research priority calls for concerted efforts to study the implications of distributed computing with respect to geographic information (and vice versa), assess likely benefits and compare them with costs, analyze the associated technical requirements, and recommend appropriate institutional arrangements and actions.

Background

Digital technology is moving rapidly to distributed computing. It is now possible for parts of a database to be stored and maintained at different locations, for users to take advantage of economical or specialized processing at r emote sites, for decision­makers to collaborate across computer networks to make decisions, and for large archives to offer access to their data to anyone connected to the Internet. These and a host of other opportunities have arisen from recent developments in hardware, software, and large­bandwidth communications technologies (see, for example, Burleson 1994; Onsrud and Rushton 1995; Annitto and Patterson 1995).

In the future, it is likely that large­scale, integrated packages such as geographic information systems (GISs) will be transformed into collections of smaller, interoperable modules. The free flow of data between the modules will be enabled by open specifications such as the open object specifications that are an industry standard and by the GIS industry's open geodata interoperability specification (known as "OGIS") (see the World Wide Web site at http://www.ogis.org; Gardels 1996). Early versions of such GIS software architectures are already appearing. Modules may coexist in one system or may be distributed across a network and assembled only when needed and with minimal user intervention. We are seeing the rapid implementation of such technology in the form of "add­ons" to World Wide Web browsers and in languages like Java.

The field of geographic information science seems set to take significant advantage of these technologies. Moreover, the problems and applications that GISs address seem particularly suited to take advantage of distributed computing. Geographic decisions supported by GISs must often be made by many stakeholder groups who are distributed both geographically and socially. In addition, stakeholders are often located in different tiers of an administrative hierarchy. Data custodian s may also be distributed, as may be the power to process geographic data with sophisticated software and hardware. Nevertheless, a host of issues arises with the implementation of distributed architectures, some technical and some institutional. Thus, the research community, through the University Consortium for Geographic Information Science (UCGIS), proposes to conduct a series of systematic studies of the opportunities and impacts of distributed computing.

In this new environment, it is important that activities focused on geographic information be embedded firmly within broader trends affecting the computing world generally. In the future, geographic information will likely be full y integrated with other information types, and as familiar to computer users of the future as text and numerical information are today. But we need to take the necessary steps today to ensure that this will happen.

GISs have already adapted to several changes in computing architectures. Early mainframe systems were quickly extended to remote sites through the use of phone lines and terminals. The minicomputers of the late 1970s were replace d by workstations and personal computers that were increasingly networked for exchange of data. Client-server architectures were adopted in the late 1980s, in a first step towards distributed software. Today such architectures are being generalized to full distribution, and the user may be presented with an integrated view of the system that bears little relationship to the system's actual structure. Indeed, we may reach a time when the entire global network is best conceived as a single, integrated "computer."

Each of these changes in computing architectures has stimulated new growth in applications, in managerial and institutional arrangements, and in the basic economics of GISs and geographic data in general. These changes are likely to continue as technology moves to fully distributed computing architectures. Such architectures will likely provide the opportunity for the GIS community to interact with entire new communities, particularly the library community, and for geographic information to become even more important to a range of human activities.

The UCGIS Approach

We need to study the effects that implementing distributed computing architectures will have and the opportunities that they offer to GISs and geographic information in general. Such studies will require specialists in the technical aspects of the architectures, such as computer scientists, communications experts, and computer engineers. Effective research will also require the skills of geographers, economists, information scientists, digital librarians, and experts in public policy. UCGIS will play a key role in providing the institutional framework to link experts from these disciplines in a coordinated approach and to develop partnerships with software vendors and other institutions.

Importance to National Research Needs

Society is being driven by an unprecedented rate of advance in digital technology. We need to anticipate the new applications and services that will become possible and to assess the costs and benefits associated with each of them so that we can continue to push for more economical public services and more competitive private ones. We need to take advantage of new technologies in education and research. Because institutions are generally slow to change, it is even more important for us to anticipate the effects that technological changes are likely to have on them so we can help positive changes occur more quickly and minimize negative impacts. Although the proposed research will focus on geographic information, it needs to be carried out in full collaboration with more general research activities.

Benefits

The following are examples of the likely benefits from the proposed research:

• Cost reductions: Monolithic solutions, which fail to take advantage of distributed computing architectures, are likely to become increasingly more expensive. By examining the costs and benefits of alternative architectures, this research will provide the basis for detailed cost/benefit analyses and decisions that should lead to cost reductions.

 
• Distributed custodianship: The National Spatial Data Infrastructure (NSDI) calls for a system of partnerships to produce a future national framework for data as a patchwork quilt of information collected at different scales and produced and maintained by different governments and agencies. NSDI will require novel arrangements for framework management, area integration, and data distribution. This research will examine the basic feasibility and likely effects of such distributed custodianship in the context of distributed computing architectures and determine the institutional structures that must evolve to support such custodianship.

 
• Distributed updating: Similar concepts of distributed custodianship, distributed responsibility for data updating, and distributed processing underlie efforts to apply geographic information technologies in transportation, to aid navigation by drivers, route planning, and many other tasks.

 
• Data integration: This research will contribute to the integration of geographic information and GISs into the mainstream of future libraries, which are likely to have full digital capacity. The digital libraries of the future will offer services for manipulating and processing data as well as for simple searches and retrieval.

 
• Missed opportunities: By anticipating the impact that a rapidly advancing technology will have on GISs, this research will allow the GIS community to take better advantage of the opportunities that the technology offers.

Short term

Examine the status and compatibility of standards across the full domain of distributed computing architectures and geographic information at national and international levels; identify important gaps and duplications; examine the adaptability of standards to rapid technological change; evaluate the degree to which geographic information standards and architectures are compliant with and embedded in such emerging frameworks as CORBA and COM/OLE; recommend appropriate actions. 
 
• Build models of GIS activities as collections of special services in distributed object environments to support their integration into much broader modeling frameworks. This will help promote the longer term objective of making GIS services readily accessible within the general computing environments of the future.

 
• Initiate an effort to create a prototype for GIS courses taught jointly by two or more UCGIS institutions, to evaluate the ability of current and near­future technologies to support such courses, and to assess the suit ability of such courses for nontraditional approaches to GIS education.

 
• Examine the relationship between the possibility of distributed courses and current institutional arrangements in higher education, and place such courses within the context of evolving structures for distributed education.

 
• Develop an economic model of the distributed processing of geographic information; include various assumptions about the distribution of costs and use the economic model to develop a model of distributed GIS computing for t he academic community.

 
• Modify commonly used teaching materials in GIS to incorporate new material about distributed computing architectures.

 
• Develop methods for the efficient use of bandwidth in transmitting large volumes of geographic data, including progressive transmission and compression; investigate the current status of such methods for raster data; research the use of parallel methods for vector data.

• Develop improved models (i.e., structure and format) of geographic metadata to facilitate sharing of GIS data, to increase search and browse capabilities, and to allow users to evaluate appropriateness of use or allow compilers to judge fitness of data for inclusion in GIS.

 
• Examine the implications of distributed computing with respect to intellectual property rights to geographic information and within the context of broader developments in this area.

 
• Examine the social implications of distributed computing and its impacts on existing institutions and institutional arrangements.

 
• Conduct case studies examining the application of distributed computing in GISs, including horizontal applications (with data distributed across different locations), and vertical applications (with data distributed at different levels in the administrative hierarchy).

 
• Monitor the progress of research addressing the technical problems that distributed computing architectures pose with regard to geographic information, including maintenance of data integrity, fusion and integration of data , and automated generalization.

Annitto, R. N., and B. L. Patterson, 1995. A new paradigm for GIS data communications. Journal of the Urban and Regional Information Systems Association 7(1): 64-67.

Burleson, D. K., 1994. Managing Distributed Databases: Building Bridges Between Database Islands. New York: Wiley.

Gardels, K., 1996. The Open GIS approach to distributed geodata and geoprocessing. Proceedings, Third International Conference/Workshop on Integrating GIS and Environmental Modeling, Santa Fe, NM, January 21-25. http://www.ncgia.ucsb.edu/conf/SANTA_FE_CD-ROM/sf_papers/gardels_kenn/ogismodl.html.

Onsrud, H. J., and G. Rushton, editors, 1995. Sharing Geographic Information. New Brunswick, NJ: Center for Urban Policy Research, Rutgers University.