Hi All,

Any thoughts on common/best practice for account number obfuscation ?

I've looked at classical character substitution/transposition algorithms, XOR (Base64) based approaches, TDES public/private key and one-way MD5 message digest approach as well......

I have account numbers - alphanumeric - that I would like to obfuscate (ideally one-way).

My only requirements -- are that the:

* cipher text is the same number of characters as the "plain text" (i.e. MD5 too long, transposition might work but I'm not sure about uniqueness)

* cipher text remains alphanumeric -- no =!@#$%& etc. symbolics introduced into the cipher (i.e. XOR type not really helpfull)

* cipher text does not need to be as strong as TDES but a little harder than Base64 or simple character substitution/shift/mapping ?

* cipher text is unique -- so that audits and history info. -- based on the obfucated/cipher-text is not corrupted by the algorithm producing the same result for two different account numbers.

Any thoughts would be greatly appreciated...

Thanks

Frank