Multikey crypto

[Mike Markley]

Since I am relatively new to the field of encryption forgive me if this 
is a FAQ.

Has anyone ever done anything with an encryption scheme that allows 
multiple unlocking keys? What I'm thinking about is a way to encrypt 
some data and then create multiple keys that will decrypt the data. I 
want to be able to encrypt a document and then give multiple people 
access to the document and be able to lock out a key and/or generate 
new keys without having to redistribute keys to everybody that already 
has one. I realize that this makes it easier to attack the encrypted 
information since there are multiple keys to unlock the data but I 
don't consider this a big problem. If someone wants to throw heavy duty 
horsepower at the problem they will crack it eventually anyway.

Mike

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Mike Markley              || The opinions here do not represent the
mmarkley at microsoft.com    || opinions of my employer. Attempts to
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   "I want to look at life, In the available light"
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