fail secure systems

[CISSP_Candidate]

Does anyone know what a fail-secure system is?

Question 13 in the sample CISSP questions from the ISC2 guide asks about a fail-secure system. The question and given answer are below

Q: The common criteeria defines the term "Fail Secure" as:
Ans d) The preservation of secure state in the event of a failure

From the answer given above it sounds very similar to a fail-soft system. But then again it could also be a fail-safe system. To the best of my understanding the secure state is maintained in both of the above cases - except that in the fail safe system all processes except the one that failed will continue operating.

Am I correct in my analysis? Anybody care to comment?

I tried the regular resources (google, books, wikipedia) but did not come up with anything Sad

[Jescoi]

The following is from wikipedia "http://en.wikipedia.org/wiki/Fail-secure"

"Fail-secure
A device which, if (or when) it fails, fails in a way that will cause no harm or at least a minimum of harm to other devices or danger to personnel, but doesn't cause the system to be insecure. The primary use of the term is with regards to security doors and motorized gates. As far as motorized gates are concerned, a motor that has "Fail-secure" capabilities will, in case of a power outage, be able to be opened by using a supplied hand crank. A fail-safe motor would let anyone open the gate if the power goes out, where a fail-secure motor would only let someone open it with a supplied hand crank if the power goes out. "

Imagine that you are in a data center and that a disaster strikes and you have to evacuate. If the power goes off and the door is fail-secure, no one would be able to open it. But if the door is fail-safe or fail-open, then it facilitates the evacuation. But the security of the data center is compromised. Since people are more important, fail-safe or fail-open is preferred over fail-secure in this scenario.