The Solaris Express program is now offered as an option for Sun’s customers to gain early access to the next Solaris release. This program is updated every month. We highly encourage people to download and install these early releases so they will have access to new features coming in
the Solaris OS.

For more information, to read the complete article, or view product documentation, so you can reference that site for specific technical diagrams, check out:

http://www.sun.com/bigadmin/features/articles/using_lu.html