master keying

[pickersRus]

Hi , I have two quick questions about master keying. Hope these are not stupid questions but I was wondering (1) Will master keying a buliding not make it less secure ? By this I do not mean less secure as in one key opening all locks but I mean less secure as in the pins being less strong since it is basically one pin on top of the other thereby giving less length and less strength to the pin. (2) Would it not also be easier to pick a master keyed lock since you would have two differnet locations on the pins to attempt to set ?

[WhiteHat]

it definately makes it much easier to set the pins.

also have a read of mat blaze's document here:

http://www.crypto.com/papers/mk.pdf (link to pdf)

[rakemaster]

I agree about how master keying makes the locks ez to pick and all but
I dont understand what you mean about being less strong because
the pins are shorter. Do you mean like people opening the lock
by breaking the pins? Ive never heard of being able to open
a lock that way. Also even if you could why would the pins being
shorter make a dif?

Rakemaster

[pickersRus]

Rakemaster , I guess the part about pins being shorter was kinda stupid. But the point I was trying to find out about is if the pins are shorter wouldn't that make it less secure in the sense that just "playing around with the lock" as in raking , or bouncing the lock around that it could be easier to get the lock to open since the pins would be in a more easier to "accidently" set position. Hope this makes sense , I am at a loss for words to really state what I am trying to ask.

[hoho]

I think i understand what you're getting at. And I think the answer is yes, but not for that reason.

The reason that master-keyed locks are easier to pick is because there are now two or more different shear lines for each pin that's master keyed. It doesn't make a difference how long the pins are, the issue is that there are now three pins with two seperate gaps in between. It just increases the chances of getting the pins to the shear line, you're right.

[rakemaster]

OK I see what your saying.

With master keys, its like you get 2 chances to pick each pin.
If you overset the first cut you can get the second.

Rakemaster

[hoho]

Exactly.

And it doesn't matter which cut you get, like it does with an interchangable-core lock. In those, you need to get either all low cuts or all high cuts, or else half the pins will be set to open the lock and the other half will be set to pull the entire core out.

[CaptHook]

Also less secure if the locksmith didnt check his system for phantoms (keys that open locks they shouldnt).
Chuck

[HeadHunterCEO]

Exactly.

And it doesn't matter which cut you get, like it does with an interchangable-core lock. In those, you need to get either all low cuts or all high cuts, or else half the pins will be set to open the lock and the other half will be set to pull the entire core out.

that is not true of all ic locks