Novell's Linux security offering, AppArmor is to have its source code released. The application, which secures Web servers and e-mail and instant-messaging systems against network-based attacks, was acquired by Novell last May when the company took over Immunix. It now ships with SuSE Linux.

Charles Ungashick, Novell’s director of product marketing, said AppArmor can scale to multiple machines and is easier to administer than SELinux. “With SELinux, you have to write a lot of low-level code at the lowest level of the OS,” he said. “It is difficult for mere mortals to implement.”

The CTO of Tresys Technology, Frank Mayer, disagrees though. "The glory of SELinux is that it can scale to any level, up or down," he argued.