" laser beams can be modulated to carry more intelligence than radio” 7 6 5 4 3 2 1 E B R S A L N C M U D O T Y I H Għ 6 5 4 3 2 1 E B R S A L N C M U D O T Y I H G KEY : 7 5 2 1 4 3 6 E R A L S B M C N U D O T Y I H Għ 5 2 1 4 3 6 E R A L S B M C N U D O T Y I H G Solution is : “bselare nscamab lodemua cdtteoa rymrroe lteinli tncg eeh iraando”ġ0 Another Example: 2 Let key : COMPUTER PLAIN: Plain text : " laser beams can be modulated to carry more intelligence than radio” Key is: Digram and trigram frequency tables can be useful.ġ 2 3 4 5 T H E S I M P L O B R A N X 1 5 3 4 2 T I E S H M L P O B R N A X The key : 15342 The cipher is :TIESH MSLEP TSOSP ITLEB RPNSA OIITS OXSXN For the type of columnar transposition just shown, cryptanalysis is fairly straightforward and involves laying out the ciphertext in a matrix and playing around with column positions. A pure transposition cipher is easily recognized because it has the same letter frequencies as the original plaintext. Make the statement in 5 columns: 4 1 5 3 2 S T I E H M L P O B R N A X Key: 41532 Cipher: STIEH EMSLP STSOP EITLB SRPNA TOIIS XOXSN A more complex transposition cipher is to write the message in a rectangle, row by row, and read the message off shuffling the order of the columns in each row. Make the statement in 5 columns: “the simplest possible transpositions” 1 2 3 4 5 T H E S I M P L O B R A N XĤ 1 5 3 2 S T I E H M L P O B R N A X 1 2 3 4 5 T H E S I M P L O B R A N X Presentation on theme: "Row Transposition Ciphers"- Presentation transcript:Ī more complex transposition write letters of message out in rows over a specified number of columns (key length) Then reorder the columns according to some key before reading off the rows Key : Plain text : the simplest possible transpositions.
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