Encryption Product Keys : Public and Private key encryption

Posted by Aran Mulholland on Stack Overflow See other posts from Stack Overflow or by Aran Mulholland
Published on 2010-06-17T00:35:26Z Indexed on 2010/06/17 0:42 UTC
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c#

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encryption

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rsa

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license-key

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public-key-encryption

I need to generate and validate product keys and have been thinking about using a public/private key system.

I generate our product keys based on

a client name (which could be a variable length string)
a 6 digit serial number.

It would be good if the product key would be of a manageable length (16 characters or so)

I need to encrypt them at the base and then distrubute the decryption/validation system. As our system is written in managed code (.NET) we dont want to distribute the encryption system, only the decryption. I need a public private key seems a good way to do this, encrypt with the one key that i keep and distribute the other key needed for decrpytion/verification.

What is an appropriate mechanism to do this with the above requirements?

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