Substitution Techniques

2
   

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`         !"#  $%&    '  &   ( ) ( %   # (          *( $(   ' ( ) % % ! #   # (     !  ( ) %  ( %#&  ! ( 

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2
 `      #(   (!&  &  & &   #(     !"#&   &     ( %(   & (    (   & ( 

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+

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`      &   (   -  !&.      (!&   (  # ! ( &  ‡  )&! #%  /   (" ‡  ( )0123 -.4567 *89:  ; ?@

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@
 ‡ Plain text : meet toga party ‡ Ciphertext: PHHW PH SDUWB

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me

after

DIWHU

     

WKH

the WRJD

A

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`        (   &) &; |+,A  *  % (  )$! # ! ( ' O â
$'â$ 'â$ C' !B  â0
$O'â0$ O'â$O D ' !B

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B

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  `  ` ‡ Key space: {0, 1, ..., 25} ‡ Vulnerable to brute-force attacks. ‡ Major weakness of Caesar cipher is its Predictability

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E

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 2
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   )  &!#%  / ("  ; 0961-@.:    ) #   (   (   ):-717:?.83 =1*0911881=?

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F

D  `    5   ( &  (! # !( &    )? (!&  G037H

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ð 
`    7(  #(    ((&I&I&  ) 3 (   )3  (   )=866:*8-

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ð

`    5((   ( %   (   (      *  ð

`    &   (   -  !& :    |A,&  !#   # !@# 

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ð

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