Thin clients

The term "thin client" has changed it's public meaning a number of times over the past several years. Essentially, though, the idea is to distribute only the presentation layer of the application to the client machines. The reason that this is attractive is that there should be zero deployment, meaning that improvements or fixes can be applied to the application without the need to install or change anything on each user's PC.

If you have used "green screen" applications, where the terminal is nothing more than a window on the server-side application - this is the idea of thin client. As an industry, we are trying to turn back to the centralized approach that works so well (instead of the chaos of redundancy of having a mainframe on everyone's desk).

How to do the thin client architecture has been the subject of much debate in the IT industry. SAP would have tried to convince you that they invented the three-tier (hence, thin client) approach - and that their SAPGUI product is what should be running on everyone's desktop. Many large companies accepted their approach, and deployed SAPGUI at about $3000 per seat.

Those of us who couldn't wait for the funding or delivery schedule of SAP decided to write our own thin clients using VB with winsock, our own network protocols, and server-side C programs with an RDBMS such as Oracle. A number of proprietary development tools started to show up as the benefits of thin clients became evident. The buzz-word "Total Cost of Ownership" (TCO) arose from the marketing efforts of these vendors. Any way you go at it (with or without high-powered programming tools) this approach was expensive to develop, but paid back during the maintenance phase.

Then the "Network Computer" came on the scene, and the correct approach to the thin client applications seemed to have required special hardware in the form of an NC. Since the first generation of NCs didn't support Java, the application developer was fairly constrained to using HTML for the presentation layer. The truth is that NCs didn't add any real value, other than enforcing the strategy that nothing of permanent value should be placed on the client machine.

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Thin clients

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