Err... this way would make it near impossible to decode the value.  Using
your simple example, how would the decryption routine know which value to
return when decrypting "191?"  Should it return "BJL" or "LTL?"

Also, encrypting should not be confused with hashing.  Encrypting a value
uses a 2-way algorithm so as to allow the encrypted value to be decrypted
(i.e., "abc" -> "X%2" -> "abc").  Hashing creates a theoretically unique
value that is difficult to near-impossible to "decrypt" (i.e., "abc" ->
X%2 -> ???).

I have checked out the CustomTags mentioned, but earlier versions of
ColdFusion (and, I suspect, these CustomTags) sometimes add junk on to the
end of the encryption string (perhaps, to return a fixed length string).
So, depending on whatever internal algorithm is used, encrypting "abc" with
a key of "123" may randomly produce "xyzpdq123" or "xyzpdq456" or
"xyzpdq789".  Note how in this (admittedly contrived) example, the first 6
characters are the same... only the last 3 differ from outcome to outcome.
In decrypting, the function/CustomTag somehow detects that only the 1st 6
characters are relevant and uses those to decrypt the string back to its
original value.

--
Mosh Teitelbaum
evoch, LLC
Tel: (301) 625-9191
Fax: (301) 933-3651
Email: [EMAIL PROTECTED]
WWW: http://www.evoch.com/


> -----Original Message-----
> From: Matthew Small [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, November 20, 2002 3:49 PM
> To: CF-Talk
> Subject: RE: Encryption gurus please read
>
>
> I think it's because encrypted values are not evaluated for their own
> value, but are rather hashed - thereby there can be more than one value
> that hashes out to the same value.
>
> Simple Example: I have a decimal number that needs to be encrypted if
> A=0, b=1,...j = 9, k = 0, l = 1, then I can have multiple values that
> evaluate to the same number.  It's similar to clock or modular
> arithmetic.
>
> BJL = 191
> LTL = 191
>
>
> Matthew Small
> IT Supervisor
> Showstopper National Dance Competitions
> 3660 Old Kings Hwy
> Murrells Inlet, SC 29576
> 843-357-1847
> http://www.showstopperonline.com
>
> -----Original Message-----
> From: Bryan Stevenson [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, November 20, 2002 3:25 PM
> To: CF-Talk
> Subject: Encryption gurus please read
>
> Hey All,
>
> I'm not entirely sure why I'm getting the results I am, so I'll ask this
> question:
>
> Why is it that the returned encrypted value can vary even though the
> string
> being encrypted and the key used remains constant (i.e. when encrypting
> "yeehaw" with the key "boohoo" will not always return the same encrypted
> value)?
>
> BTW I've tested this situation against cf_cryp, cf_crypt, and Encrypt()
>
> TIA ;-)
>
> Bryan Stevenson B.Comm.
> VP & Director of E-Commerce Development
> Electric Edge Systems Group Inc.
> t. 250.920.8830
> e. [EMAIL PROTECTED]
>
> ---------------------------------------------------------
> Macromedia Associate Partner
> www.macromedia.com
> ---------------------------------------------------------
> Vancouver Island ColdFusion Users Group
> Founder & Director
> www.cfug-vancouverisland.com
>
>
> 
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