Re: Is there any way...

On Feb 27, 8:46 pm, Hilltop...@xxxxxxxxxxxxx wrote:
On Feb 27, 6:29 pm, "Studio Janck" <StudioJa...@xxxxxxxxx> wrote:

To get an encryption key from an encrypted file or string IF you have
the exact original? Is there a program that can "compare" them and
find out what the encryption key was?

Depends on the algorithm used. A simple stream cipher using a 32-bit
Linear Congruential Generator can be cracked with as little as 4 bytes
of known plaintext (if the LCG parameters are known). Simple
substitution ciphers can be cracked with enough plaintext using
frequency counts of characters. The German Enigma machine was cracked
using known plaintext during World War II.

Richard Mueller

I'm talking about DES encryption, sorry I didn't mention that earlier.

.

Relevant Pages

  • Re: Is there any way...
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    (sci.crypt)
  • Re: Advantages of stream ciphers over block ciphers in CTR mode?
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  • Re: Advantages of stream ciphers over block ciphers in CTR mode?
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  • Re: Advantages of stream ciphers over block ciphers in CTR mode?
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