What is JAAS

The Java Authentication and Authorization Service is a package developed to allow user authentication over a wide variety of methods from password authentication through smartcards and biometrics.
It extends the Java 2 Platform's security mechanism so that access to code sections can be restricted by not only where it came from, or who signed the package, but also who is currently using the functionality.
It is a Java implementation of the Pluggable Authentication Module (PAM) framework

The Java Authentication and Authorization Service is a package developed to allow user authentication over a wide variety of methods from password authentication through smartcards and biometrics.