In this section, we'll concentrate on the elements of authentication in JAAS. We'll start with a description of a simple login and authentication procedure, which will give you a high-level view of the JAAS authentication architecture. Following that, we'll discuss each piece of the architecture in detail. At the end of the section, you'll have the opportunity to study the code for two login modules in detail.

If you haven't already done so, now is the time to download the source code for this tutorial, JavaSecurity2-source.jar. The source will better illustrate the steps outlined in the discussion that follows.