Chapter 4. Drawbridges

Drawbridges are the information pipeline for the enterprise architecture. They are the basis for fortress interoperability. They carry messages from one fortress to another.

Many companies treat drawbridges as second-class citizens that take a back seat to the higher-profile fortress technologies. For example, I have seen many companies worry ad nauseam about whether to use J2EE or .NET for a particular software fortress, a decision that has relatively little long-term impact. The same companies then spend very little time worrying about their drawbridge technologies, even though bad choices here have serious long- term ramifications on the overall enterprise architecture. Drawbridge choices affect not only interoperability, but also scalability, reliability, security, transaction support, and overall system responsiveness.

In this chapter I give an overview of drawbridges. I will discuss the different types of drawbridges in more detail, as well as how to choose among them, in Chapters 5 and 6.

As always, if you find yourself having trouble with specific terms or acronyms, refer to the glossary.