Re: Cracking decrypted file when knowing partial contents

From: David A. Scott (daVvid_a_scott_at_email.com)
Date: 04/21/04 

Date: 21 Apr 2004 02:13:59 GMT

unruh@string.physics.ubc.ca (Bill Unruh) wrote in
news:c6472g$312$1@string.physics.ubc.ca:

>
> No encryption can guarentee anything. They are however designed to be
> resistant to known plaintext attacks (ie attacks which make use of
> knowing both the plaintext and the encrypted text). Any crypto system
> which is weak if plaintext is known, is weak period.
>
>

  No even systems your talking about are weak in the sense that a
few paragraphs of plaintext would be more than enough to guarantee
that an attacker has all the information necessiary for a break.
What your calling strong are only strong because there are no published
breaks but that does not mean someone will not find a trival break.
What is strong today tends to become weak as time marches on.

David A. Scott 

-- 
My Crypto code
http://cryptography.org/cgi-bin/crypto.cgi/Misc/scott19u.zip
http://cryptography.org/cgi-bin/crypto.cgi/Misc/scott16u.zip
http://www.jim.com/jamesd/Kong/scott19u.zip old version
My Compression code http://bijective.dogma.net/
**TO EMAIL ME drop the roman "five" **
Disclaimer:I am in no way responsible for any of the statements
 made in the above text. For all I know I might be drugged.
As a famous person once said "any cryptograhic
system is only as strong as its weakest link"

Relevant Pages

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  • Re: Cracking decrypted file when knowing partial contents
    ... ]> No encryption can guarentee anything. ... ]> resistant to known plaintext attacks (ie attacks which make use of ... ]> knowing both the plaintext and the encrypted text). ... If your secret must really remain secret but readable ...
    (sci.crypt)