THE

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THE ENIGMA EXPERIENCE DAY 1
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Aoccdrnig to rscheearch at an Elingsh uinervtisy,
it deosnt mttaer in waht oredr the ltteers in a
wrod are, the olny iprmoetnt tihng is taht the
frist and lsat lttrees are in the rghit pclae.
The rset can be a toatl mses and you can sitll
raed it wouthit any porbelm. Tihs is bcuseae we
do not raed ervry lteter by itslef but raed the
wrod as a wlohe. Hwoveer, dnot try tihs wtih
nmrbeus!
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HISTORY

• The history of cryptography begins thousands of
  years ago. Until recent decades, it has been the
  story of what might be called classic
  cryptography that is, of methods of encryption
  that use pen and paper, or perhaps simple
  mechanical aids.
• In the early 20th century, the invention of
  complex mechanical and electromechanical
  machines, such as the Enigma rotor machine,
  provided more sophisticated and efficient means
  of encryption and the subsequent introduction of
  electronics and computing has allowed elaborate
  schemes of still greater complexity, most of
  which are entirely unsuited to pen and paper.

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HISTORY

• The development of cryptography has been
  paralleled by the development of cryptanalysis
  of the "breaking" of codes and ciphers.
• The discovery and application, early on, of
  frequency analysis to the reading of encrypted
  communications has on occasion altered the course
  of history. Thus the Zimmermann Telegram
  triggered the United States' entry into World War
  I and Allied reading of Nazi Germany's ciphers
  shortened World War II, in some evaluations by as
  much as two years.

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Lets do some
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Scrambled Messages
Take a sentence
I LIKE DRINKING LEMONADE WITH ICE IN
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and regroup
ILIKE DRINK INGLE MONAD EWITH ICEIN
or
ILI KED RIN KIN GLE MON ADE WIT HIC EIN
Trickier?
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or write backwards
NI ECI HTIW EDANOMEL GNIKNIRD EKIL I
and then regroup
NIEC IHTI WEDA NOME LGNI KNIR DEKILI
Trickier still?
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Try for yourselves
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THE ENIGMA EXPERIENCE DAY 1
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Another way of arranging the letters
I LIKE DRINKING LEMONADE WITH ICE IN
First re-write it on two lines Dropping every
second letter
I I E R N I G E O A E I H
C I L K D I K N L M N D
W T I E N
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I I E R N I G E O A E I H
C I L K D I K N L M N D
W T I E N
Write the second line after the first
IIERNIGEOAEIHCI LKDIKNLMNDWTIEN
Put it in groups of five
IIERN IGEOA EIHCI LKDIK NLMND WTIEN
Trickier still?
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I I E R N I G E O A E I H
C I L K D I K N L M N D
W T I E N
Write the first line after the second
LKDIKNLMNDWTIEN IIERNIGEOAEIHCI
Put it in groups of five
LKDIK NLMND WTIEN IIERN IGEOA EIHCI
Trickier still?
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We could write the message on three lines
I K R K G M A W H
E L E I I L O D
I I I I D N N E
N E T C N
Now we have a choice of how to arrange Lets do
2nd, 1st and 3rd
LEIILODIII IKRKGMAWHE IDNNENETCN
Put it in groups of five
LEIIL ODIII IKRKG MAWHE IDNNE NETCN
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Can you code this?
MATHEMATICS IS NOT JUST ABOUT NUMBERS
Use two or three lines Order 1st, 2nd (and
3rd) Then group in 4s
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MATHEMATICS IS NOT JUST ABOUT NUMBERS
MTEA ISSO JSAO TUBR AHMT CINT UTBU NMES
or
MHAC STSB TMRA ETSN JTON BSTM IIOU AUUE
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But can you decipher
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Recovering the message
AETOA TCHTM HNTSA ET
Could it be a two-line message?
It has 17 letters, so divide into 9 and 8
AETOATCHT MHNTSAET
Put into two lines
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AETOATCHT MHNTSAET
A E T O A T C H T M H N T
S A E T
Fit one line into another
A M E H T N O T A S T A C E H T T
Look at it from right to left Doesnt look quite
right?
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Recovering the message
AETOA TCHTM HNTSA ET
Could it be a two-line message?
It has 17 letters, so divide into 8 and 9
AETOATCH TMHNTSAET
Put into two lines
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AETOATCH TMHNTSAET
A E T O A T C H T M H N T
S A E T
Fit one line into another
T A M E H T N O T A S T A C E H T
Look at it from right to left Get it?
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Try for yourselves
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THE ENIGMA EXPERIENCE DAY 1
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THE ENIGMA MACHINE

• 159 million million million to 1!!!
• But why?
• How does it work?

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The Cipher Wheel
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The Cipher Wheel
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Lets cipher our names

• To cipher a letter, read the inner wheel and to
  decipher a letter, read the outer wheel.
• MS KORMAZ
• FL DHKFTS

And your name is
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• Try deciphering this message
• NEOI MW E HSYFPI EKIRX

HINT a four letter shift
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• JAKE IS A DOUBLE AGENT

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Can you cipher the following

• Various intelligence evidence during World War
  two led the German military to make several
  investigations about the possibility that The
  Allies can read Enigma messages. The German
  intelligence and communications experts concluded
  that Enigma was still secure from allied code
  breakers. They were wrong.

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Getting back into "Shark".

• The story of the film revolves around Bletchley
  Park being unable to decipher the U-boat signals
  because the German Navy had changed the Short
  Weather Signal Book which the codebreakers had
  been using for "cribs".
• This blackout occurred just as three large
  convoys were proceeding from America to the UK.
• It was imperative to find out where the U-boats
  were so that the convoys could be diverted
  awayfrom the U-boats.

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Getting back into "Shark".

• In the film, Bletchley Park code-breakers had no
  idea how to restart breaking the Naval Enigma
  cipher, called Shark.
• So they turned to Tom Jericho who had been the
  person who broke it in the first place.

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Getting back into "Shark".

• Jericho who had suffered a nervous breakdown and
  had been sent back to Cambridge from Bletchley
  Park was brought back to the Park.

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Getting back into "Shark".

• In the film Jericho realised that the short
  signals from U-boats when they sighted a convoy
  could be used to discover the Enigma settings and
  thus get back into breaking the Naval Enigma
  cipher, Shark.

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Getting back into "Shark".

• Lets look at the codebreakers at work.

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LETS SHARE OUR LEARNING WITH THE SCHOOL

• YOUR TASK
• Make a display on codes and ciphers