by Raphael Sussman

The dream of e-government is to combine data from limitless sources and make information available at the touch of a button. With web-based interoperability, this is now possible by making data and functionality available from many sources without physically combining the data or requiring any software – something much harder than it sounds. Geospatial data-based services provides an example of how to build this capability and make the dream a reality.

Interoperability allows us to share well-managed data sets in real time. Land Information Ontario (LIO) goes one step further to ensure that data are collected efficiently, without duplication, and using accepted standards. LIO was mandated to make Ontario’s land information managed, accessible, integrated and affordable through the development of strategic partnerships. LIO has built an information infrastructure of people, processes, data, physical elements and agreements. More than 250 organizations share data through LIO’s infrastructure under formal agreements.

Data in the LIO warehouse is now accessible through Web Mapping Services and through the cutting-edge technology of Web Feature Services. For such web-based interoperability to work, everyone must abide by the same standards.

It is then possible to combine various data sets and functions from multiple websites to create a custom ‘application’. This allows us to create dynamic maps for analysis, without having any local Geographic Information System (GIS) software, and use data from many locations. Like many industries, the Geomatics community has developed its own standards. The current front-runner is the Web Mapping Service (WMS), as defined by the Open Geospatial Consortium (OGC). WMS combines geospatial data from a number of servers in an OGC-compliant format. From a technical perspective, WMS combines independent data elements, without integrating the data sets. Web Feature Services (WFS), which support a variety of purposes, are the next wave of computing architecture. WFS are largely vendor independent, flexible, simple to implement, easily to upgrade, and inexpensive. By being permanently connected to the internet, WFS formally blur the line between data and functionality.

However, technology alone will not make WFS work. WFS are built on true interoperability, of which there are three basic types. Technical (physical) interoperability involves the ability to share and exchange data. It requires data definition, a prior agreement on alphabets, coding structures, graphic representation, media, forms, etc. Information (semantic) interoperability involves the ability to share and exchange meaning. It requires data mapping, a prior agreement on definitions and description of context.

Business (functional) interoperability involves the ability to share and exchange tasks, obligations and commitments. It requires data use rules, a prior agreement on legal frameworks, agreements, processes and roles. Descriptions of all three types of interoperability must be recorded in order for computers to read and interpret data, making it available for both discovering and sharing. Internal and public portals, open search engines, and most off-the-shelf applications can use this data.

Most business functions are discrete, and traditionally data sets are designed to meet that need. Sharing data has been possible, but is a major accomplishment every time. Actually creating and managing multi-purpose Enterprise data sets is the exception, rather than the rule. For Geomatics, the most common mode of data sharing is through a centralized, physical data warehouse with a number of base data features acquired and/or maintained by a single organizational unit.

These base data features can be physical (e.g., centre of road) or nonphysical (e.g., parcel boundary). Other users then add their own features of interest relative to these base features. Underground utilities, for example, may be placed relative to a building edge.

With the advent of geospatial data clearinghouses such as Land Information Ontario, it is now possible to surpass a single group of organizations to use existing data sets as needed. Until recently, once data was discovered, the only options available were to either download the data sets of interest or view the data within a local, custombuilt Internet Map Server (IMS). Now, all major GIS software offers IMS and many organizations use this function to display interactive geographic data on their internet and/or intranet sites for people to use as needed.

Organizations like LIO, with a specialty in geospatial data management, are often the leaders in their organizations for introducing new technological concepts and formal cooperative structures for sharing data, functionality and services. GIS units within government are frequently used because of their connection to all aspects of the organization. This is because the data sets involved are clearly common, clearly distinct in structure, and clearly limited in number. Broad-based geospatial data sharing and use is probably in your organization now. Because GIS units tend to be small and self-contained, their negative effects are limited, while their potential is limitless. If you have not done so already, give them the chance to make your organization shine.



Raphael Sussman is a professional Geographic Information Systems (GIS) manager, urban and regional planner, landscape architect, and Ontario land surveyor. He worked for many years in municipal government, specializing in GIS, and is now manager of Land Information Ontario (raphael.sussman@mnr.gov.on.ca).