Pattern-Oriented Software Architecture For Dummies

Chapter 15

Putting Key Functions in a Microkernel

In This Chapter

• Designing a simple, compact system core
• Implementing a microkernel

In this chapter, I tell you about a sophisticated way of building your system around a small core of functionality. This core, or microkernel, lets you build the outside layers from efficient, small, easily changeable parts.

Although operating systems (OSes) are the most common examples of microkernels, the technique is used in many virtual-machine infrastructure packages and is useful for solving a wide variety of other problems. Security appliances that screen messages with pluggable external servers to provide new security policies are another example. A database engine example has a microkernel providing core functionality to interact with the hardware and storage. Different conceptual views of the database are provided through policies implemented in external servers.