In-Depth

Put the 'Smart' in Smart Client

Building applications for multiple platforms requires more consideration from developers than ever before. Find out how to make your apps ''smarter.''

• By Dan Fergus
• 06/08/2005

Smart Cli•ent, n.1. Easily deployed and managed client applications that provide an adaptive, responsive, and rich interactive experience by leveraging local resources and connecting intelligently to distributed data sources.

Wait, don't leave! I didn't mean to run you off with a marketing definition, but that is how Microsoft defines a Smart Client. Using real language, you might define Smart Client as "an application that provides the best of both the Thick and Thin Client architecture." The application lives on your local PC, but it behaves as though it is part "explorer."

Is this a new idea? No. If you developed an application about 10 or 12 years ago, you didn't give much thought to whether the user's PC was connected to the outside world because he or she usually didn't have a reliable connection (except for big corporate clients). Today we have Web services, client/server architectures, designs, and architectures that require you to see the world beyond your PC.

Smart Client design today is more important because the PC world is becoming more mobile. In addition to developing for desktop PCs, you now must consider mobile devices such as the Pocket PC or a tablet device. These devices permit true mobility, and developing applications for them requires a thought shift from creating connected desktop applications.

There are many talking points on Smart Clients, but here is a short list of five important goals to consider when developing them: Utilize Web services, provide support for working both online and offline, enable device adaptability, reach beyond the host device, and provide a rich user interface.

For anyone who has ever written a mobile device application, the Smart Client idea is nothing new—we've always been concerned with it. A well-written device application is knowledgeable about its surroundings, and if a connection exists it is used; if not, the application keeps on working, storing data and information until a connection reemerges. Because connection bandwidths vary, you also must make the application responsive. Here's a useful mantra when developing Smart Client applications:

If there is something out there, use it, but use it wisely. Whenever possible, code for a smaller bandwidth. Transfer data or information only when necessary. Be "smart" about your surroundings.

In general, write your applications with a closer eye to detail and provide application support both when connected and not. Take some extra time to ensure your desktop or device application is knowledgeable about the resources at its disposal. In the end, how you define "Smart Client" in your organization will differ from how I define it or even how Microsoft defines it. What's important is to carry the ideas and concepts into your daily development.