Moving the business logic tier to the client. Cost-effective distributed computing for the WWW



The Internet and the WWW have encouraged the adoption of a three-tiered architectural style as the general framework for distributed computing. The thin client concept associated with this model is the most suitable for the WWW, because it can be easily mapped to the browser concept. Additionally, the separation of business logic (middle tier) and back-end services enable further flexibility for the design of this kind of service. Nevertheless, the advent of platform-independent software models like Java and the availability of common off-the-shelf services, like FTP or HTTP, offer new opportunities to more classical distributed computing models. In this paper we revisit the two-tiered model for Internet environments, and show that the fat client (user interface plus business logic) may still be valid, at least in some environments. We propose two solutions to provide full FTP access from a Java applet. Copyright © 2001 John Wiley & Sons, Ltd.