codes ciphers
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1010 mixlplik
igpay atinlay
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Codes and ciphers have existedforhundreds of years.
People have always had theneedto hide secrets and messages.
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Caesar used ciphers and codes as didthefounding fathers of the United States.
Thomas Jeerson created ciphers andcode systems during the Americanevolution.
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Su!stitution ciphers are very commonciphers. "etters can !e reversed orrotated a certain amount.
A B C D E F G H I J K L M N O P Q ! " # $ % & ' (
' ( A B C D E F G H I J K L M N O P Q ! " # $ % &
Original Message : hello
Encoded Message : fcjjm
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A permutation can !e used to ma#e thesu!stitution cipher harder to !rea#.
A B C D E F G H I J K L M N O P Q ! " # $ % & ' (
G ' % J M N A Q ( D & $ E F " ! H # P O L C I B K
Original Message : hello
Encoded Message : qmvvt
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Su!stitution ciphers are !ro#en usingletter fre$uencies. Certain lettersoccur in the %nglish language morefre$uently than others. % occurs mostfre$uently.
A B C "
)*1+, 1*-./ /*,)/ .*0+
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Original Message : bad
Encoded Message : * * * * * *
A *
B * * *
C * *
D * *
E*
&orse code is avery
common formof cipher.
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Transpositionalciphers come in
many shapes andsi'es.
I L O $
E % O
K I N G
% I " H
C O D E
These ciphers involve storing a messagea grid and then encoding the messageusing a speci(ed pattern.
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A column ciphercould )ust run
down the columnsto ma#e a codedmessage.
I L O $
E % O
K I N G
% I " H
C O D E
Run down the columns starting with column 0.
CODED ME!"E : #E$%C&%##OOO'(D)R"*E
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A spiral ciphertypically spirals in
or out and startsat a speci(edcorner.
I L O $
E % O
K I N G
% I " H
C O D E
+rial from to+ left down and in
CODED ME!"E : #E$%CODE*"R)O&%##('O
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A pigpen cipher uses dierent shapesand dots to encode letters. The*reemasons are credited with creating
the pigpen cipher.
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"etters can !e placed in any order inthe pigpen cipher.
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A playfair cipher usesa code phrase and
a +,+ grid. -oduplicate lettersare placed in the grid.The remaining letters of the
alpha!et are used to (ll the grid.
t was used in // and //.
I L O $ E
% K N G
" H C D A
B F J M P
Q ! # $ &
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The letters to !eencoded must !e
located in the grid.
*/ is encoded to0.
S1 is encoded toU,.%A is encoded to2P.3 is encoded to
I L O $ E
% K N G
" H C D A
B F J M P
Q ! # $ &
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Use the gridto
encode pairsofletters.
I L O $ E
% K N G
" H C D A
B F J M P
Q ! # $ &
ME!"E (O CODE : %* !(
CODED ME!"E : R( (*
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The enigma machine wasused !y the -a'i regime
during /orld /ar toencode messages.
3ave eed5s%ngima
&achine
http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/ -
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&P%26 and &P%27 (les are encoded(les.
&P%2 stands for &oving Pictures%xpert 2roup. &P%2 (les arecompressed (les.
http://www.apple.com/itunes/http://www.apple.com/itunes/ -
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&P6 (les are used to compress C3$uality (les. The compressionalgorithm typically compresses (les
at a 89m! to 8m!:;m! rate. A 79m! (le would compress roughly to7m!:
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=ou must have an &P%26 compati!leplayer to play an &P%26 encoded(le.
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