[delinka]

After reading the article, and reading replies to you, I still have to guess whether this is a Linux kernel or something else. And I still don't understand why they don't mention this on their site. The talk of "kernel with certain patches" has me guessing it is indeed Linux.

[tptacek]

They are practically screaming grsec/PaX from the rooftop. It's even in the diagram! What else could they possibly be?