Breaking a Transposition Cipher
Say we have some ciphertext that we know was encrypted with a transpo-
sition cipher. At first, we assume we know the degree of the permutation.
Say the degree is 13. We arrange our ciphertext into 13 columns (perhaps
disregarding an incomplete last row).
1 2 3 4 5 6 7 8 9 10 11 12 13
t i f a t
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ok
g
r
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g
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h o o t o
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t l i
r
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e e w h c e l
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b t l a a l f e s o a n i
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e e s c
r
nozo
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v l i i u t e h f m e
g
y
e e e z s f
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hi a ot s
o t t m t e a i s h
r
hi
n o i a n l h h s
g
dt u
w a i a t
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p
esma
y
r
o i o
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o t
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sl f usb
f h e
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ecosoaf
m l t u e n a b h
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aae
h b a t v m n l t n e e u
d f e s e t t o t c e
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e s s
g
i t h n
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tsou
s i o
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d t
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ezt
t l o e a n t
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nt s l a
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i t e o n
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