Clearly, Web support is on the critical list for most application development tool vendors. They all have their own mechanisms to offer database connectivity and their own ways of distributing the process load. Another area of complexity is architecture. The use of CGI changed all this. Using a three-tier architecture, developers could create a process on the Web server that was able to pump custom dynamic HTML down to the Web client, responding to the requests of the user.
Search engines are the best example of three-tier Internet applications.
An applet is downloaded to the client, where it runs within the browser as an interactive application. If you think that's enough to worry about, you're wrong. This provides all of the benefits of using a TP monitor, including load balancing and database multiplexing. When using an n-tier architecture, developers generally layer a set of distributed objects between the CGI or Java processes and the database. With the advent of IIOP, distributed objects can even run on the browser, the Web server, the application server, or the database server.