The idea of this page is to put together and discuss different security frameworks that we could potentially use in our architecture

Apache Shiro

http://shiro.apache.org/

This is an open-source authentication/authorization framework from Apache. The interesting thing about this framework is that it provides a clean and separated way to handle not only authentication, but also authorization.

The framework claims to be extensible and pluggable and it already provides integration with other frameworks/technologies like Spring and oAuth.  Another good thing about this framework is that it is not tied to any particular technology (i.e. web container, JEE, etc); as it can be used in any java application.

The data-sources for authorization and authentication can be pluggable and, apparently, it has support for LDAP and MySQL back-ends out-of-the-box.