Transposition cipher - Network Security.ppt

Transposition cipher

1. Transposition Cipher
Edilasio Pereira
Steven Pascal
Louis Szgalsky
Kimberly Chiffens

2. 09/27/10 copyright 2006 free
template from
brainybetty.com
2
•a transposition cipheris a method of
encryption by which the positions held by units
of plaintext (which are commonly characters or
groups of characters) are shifted according to a
regular system, so that the ciphertext constitutes
a permutation of the plaintext. That is, the order
of the units is changed. Mathematically a
bijective function is used on the characters'
positions to encrypt and an inverse function to
decrypt.

3. 09/27/10 copyright 2006 free
template from
brainybetty.com
3
The Rail Fence Cipher
•POETRY IS WHAT IS LOST IN
TRANSLATION
P E R I W A I L S I T A S A I N
O T Y S H T S O T N R N L T O

4. 09/27/10 copyright 2006 free
template from
brainybetty.com
4
Rail Fence
Ciphertext
•ITIAGOAIGTSHSSOSTES

5. 09/27/10 copyright 2006 free
template from
brainybetty.com
5
...Decrypted
•T I A G O A I G T
S H S S O S T E S
•Message: IS THIS AS GOOD AS IT GETS

6. 09/27/10 copyright 2006 free
template from
brainybetty.com
6
Columnar Transposition
Message: THE GOLDEN RULE IS THAT
THERE ARE NO GOLDEN RULES

7. 09/27/10 copyright 2006 free
template from
brainybetty.com
7
Columnar Transposition (cont)
THEG
OLDE
NRUL
EIST
HATT
HERE
AREN
OGOL
DENR
ULES

8. 09/27/10 copyright 2006 free
template from
brainybetty.com
8
Columnar Transposition (cont)
TONEHHAODUHLRIAERGELEDUSTREON
EGELTTENLRS

9. 09/27/10 copyright 2006 free
template from
brainybetty.com
9
Columnar Transposition
Ciphertext
AEGLRADHNTAHSTTAETWYCEHOOCE
IKRBELMUSTVXY

10. 09/27/10 copyright 2006 free
template from
brainybetty.com
10
Columnar Decrypted
LARGE
ANDTH
ATSTH
EWAYT
HECOO
KIECR
UMBLE
STVXY
AND THATS THE WAY THE COOKIE
CRUMBLES