I’d like to thank Jdege for explaining this method. I won’t say I’m doing it 100% right but it’s my first time so go easy on me.
In cryptanalysis, contact analysis is the study of the frequency with which certain symbols precede or follow other symbols. The method is used as an aid to breaking classical ciphers.
Contact analysis is based on the fact that, in any sample of any written language, certain symbols appear adjacent to other symbols with varying frequencies. Moreover, these frequencies are roughly the same for almost all samples of that language, even when the distribution of the symbols themselves differs significantly from normal. This is true regardless of whether the symbols being used are words or letters.
In some ciphers, these properties of the natural language plaintext are preserved in the ciphertext, and have the potential to be exploited in a ciphertext-only attack.
Although in a sense contact analysis can be considered a type of frequency analysis, most discussions of frequency analysis concern themselves with the simple probabilities of the symbols in the text: P(Xi = a) or
Contact analysis is based on the conditional probability that certain letters will precede or succeed other letters: , or , or even , where S and T are subsets of the alphabet being used.
Where frequency analysis is based on first-order statistics, contact analysis is based on second or third-order statistics.
And now, to the cipher mobile!
Here are my first attempts at frequency analysis back in the day.
Here are my first attempts at digraph frequency analysis back in the day.
Now I can’t read this one…
4183463572322052403382136
-225
4033012972021902103081911
masked:
4183463572322452403382176
-225
4033012972022302103081951
considering: 180, RUASORETNILREB
meaning in general, beware of what was hatched long, long ago; it may just come to be one’ worst nightmare. S
Where in the world is San Diego?
resting in Restin
I wasrereading “The Tutankhamun Prophecies” this morning and came across inspirational words of Immanuel Velikovsky: “Don’t be afraid to face facts, and never lose your ability to ask the questions: why? and how? Be in this like a child all fruitful ideas have been conceived in the minds of nonconformists, for whom the known was still the unknown, and who often went back to begin where others passed by, sure of their way. The truth of today is theheresy of yesterday.” How true!
DIBBADFEAEBEAAEHBIAASURYC? WK
Before she passes, shouldn’ t she know? Thanks!
Karmin
Thanks Karmin, but I’m not sure I understand.