Chapter 10. Internet Fortresses

Presentation fortresses and Web service fortresses can both be categorized as Internet fortresses. Internet fortresses are the no-man's-land between your enterprise and the Internet. Internet fortresses have two main purposes. First, they mediate interactions between the outside world and your enterprise dominion . Second, they provide a security buffer between the outside world and the restricted world of the corporate computing grid. Both of these functions are depicted in Figure 10.1.

Figure 10.1. Internet Fortresses

There are two types of Internet fortresses: presentation fortresses and Web service fortresses. Presentation fortresses are specialized to deal with the browser, or thin, clients . Web service fortresses are specialized to deal with code-based clients. Web service fortresses are used relatively infrequently in today's enterprise systems; however, if one is to believe advance hype, they will become much more prevalent in the future.

I'll start by looking at the presentation fortresses because their architectures have been around the longest and are therefore the best understood . Most of what we know (or think we know) about Web service fortresses has been extrapolated from our knowledge of presentation fortresses.