The realism of combination lock security

[cipher]

In Hollywood theatrics, it is commonplace to see safes being broken using "listening" techniques. I am only a security expert in the area of computers, not physical locks, and I want to learn about the reality of these combination lock issues. How secure are these combination locks (both digital and mechanical), and how realistic are the techniques for breaking them? Thanks for you replies.

[quickpicks]

it's mostly in the feel. Its very intricate stuff and is not discussed in the 'open forums' Sorry to burst your bubble. Matt Blaze has a paper out on combo locks somewhere.

[cipher]

Had a feeling it would need to be posted in the "off limits" forums. Thanks anyway.................

So, can I infer that these locks aren't very vulnerable (like pin tumbler mechanisms)?

[quickpicks]

nope. They are nothing to even comare to a pin tumbler. Do a google search for matt blaze's crypto papers and you will find what I was talking about.

[cipher]

Yep, thanks, I'm reading his papers right now.

Also, is there some sort of comparison between keyed, combination, digital, etc, security that you can point me to?