Using COM to develop universal GIS applications

A New Breed of GIS Applications

Motivation
What started as a data repository for graphical and tabular information representing everything from environmental research to utility assets has become an organizational tool for planning futures as well as an information source for critical network topology. Geographical Information Systems are becoming a wide spread device for mass deployment of spatial data. The world of energy generation and distribution has started to see that this technology can be used throughout the enterprise for robust data collection and circulation, job design, new business and planning, as well as mission critical systems like outage management and network restoration.

Organizations are starting to plan for lightweight devices that can use GIS technology in the field to perform the same types of jobs that it is used for in the office. What problems does this present? What are the limitations of each GIS? Are they scalable enough for hundreds of users, yet portable enough to be used in a distributed or disconnected environment? Many people are discovering that one GIS solution may not be the answer.

There are probably terabytes of historical and legacy data existing today in GIS data repositories that is still up to date and usable, but because of re-organization and re-engineering new GIS platforms have been installed and implemented. Along with these new systems comes a new suite of products and applications that have to be taught. The old applications are no longer used because the GIS they were originally written for has been replaced by newer technology. As corporations currently using competing GIS technologies merge, decision about standards have to be answered, and a complete translation from one GIS to another may not be the right answer. These issues are providing today’s IT departments with new and interesting problems to solve. What is more than likely the case is that a single GIS platform may not be the best answer to these questions. A GIS that can be used easily in the office may not be the most efficient tool to use on a pen based machine in the field. Two different companies that merge, may agree that they are happy with the GIS each is using and decide not to go with only one. How do these companies continue developing a single add-on application that can be used on multiple GIS platforms?

A Solution
New technology has given a new answer. It is now possible to develop integrated applications that can run with different GIS platforms. Microsoft introduced the Component Object Model (COM) as a solution to problems like this, different environments communicating directly with one another. This technology does not come without a price, and that price is in the form of increased design and development time. Each GIS being targeted should be reviewed for required application functionality, and this functionality should be abstracted at the lowest possible level and partitioned correctly. The payoff is a uniform tool that can be used throughout the organization for everything from job design to outage management, regardless of what GIS system the user has access to.