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JBabyJ
05-01-2011, 03:26 AM
Hello everyone, I'm a newbie. I was directed to this forum for some answers. Here is the problem:

(oh, and the 1 and 2 should be subscripts after the C's)

Plaintext letter: a b c d e f g h i j k l m n o p q r s t u v w x y z
C1(k=5) f g h i j k l m n o p q r s t u v w x y z a b c d e
C2(k=19) t u v w x y z a b c d e f g h i j k l m n o p q r s

Consider the polyalphabetic system shown above. Will a chosen-plain-text attack that is able to get the plaintext encoding of the message "The quick brown fox jumps over the lazy dog" be sufficient to decode all messages? Why or why not?

pootie49
05-01-2011, 05:12 AM
HUH???

http://en.wikipedia.org/wiki/Chosen-plaintext_attack

its the best i can do. we just solve em, we dont ask why or how come?

why dont you play a few you might like them?

our illustrious fearless leader, admin, might know?! or as I call him...He who must be obeyed. (jk);)

Lurker
05-01-2011, 06:04 PM
JBabyJ, I'd love to help, but most of us can only do a simple single-substitution code. Once things get layered or involve characters other than the usual 26, we get lost.

Is there an online version of ENIGMA that you can program to do what you want?

As for the last question, "lazy dog" might work, but only if you can solve that one to get things started. A simpler phrase may not contain all the letters, but if it is more solvable, you may be able to get the rest in future decodings.

JBabyJ
05-02-2011, 01:18 AM
I want to thank you two for your replies. I'm not sure the instructor wanted us to actually break the code, he just wanted to know if it is sufficient enough to decrypt the rest of the text and understand [I]what it takes[I] to break the encryption.

Thanks again!

JBabyJ, I'd love to help, but most of us can only do a simple single-substitution code. Once things get layered or involve characters other than the usual 26, we get lost.

Is there an online version of ENIGMA that you can program to do what you want?

As for the last question, "lazy dog" might work, but only if you can solve that one to get things started. A simpler phrase may not contain all the letters, but if it is more solvable, you may be able to get the rest in future decodings.