1. Code Breakers and Makers
Name

2. Does Secrecy protect Peace?
YES NO
Extra question: ‘Does the use of codes keep our world safe?’
If they think it protects peace they stand on one side of
the room, if they think it doesn’t protect peace they stand on the other side of the room. If they are somewhere in
the middle – they stand along the line depending on how strongly they support either view.
Teacher to then encourage students through questioning to explain why they have the opinion that they do –
make sure an appropriate number of responses from each side of the viewpoint is examined. Students can move along the line if they are convinced by their peers arguments.

3. Where did CODE BREaking start?
Since humans beings were able to communicate they have attempted to obscure information from one another in order to keep things secret. One way to do this is code.
Those making codes are called Cryptographers. They give the cipher or way to solve the code to the person receiving the message. Without the cipher, messages remain unbroken and therefore hidden until someone ‘cracks’ the code.
People who use logic/intuition and complex mathematical systems to ‘crack’ the codes are called cryptanalysts or code breakers.
The Greeks and Romans were some of the first civilisations to use sophisticated ciphers to communicate secretly. Polybius created a system whereby each letter on a grid would be replaced with a letter from the alphabet in a 5x5 grid. (A = 1x1 = 2 or N = 3x3 = 9)
Caesar invented a cipher that shifted the letters of the alphabet by a certain number of letters or numbers i.e. (A=2 B = 3, C = 4 or A = B, B = C, C = D).
These two systems have formed the basis of many codes throughout history!

4. Codes continued to advance in a similar way until the invention of the telegraph machine and Morse Code. This allowed nations to transmit codes across large distances to each other easily in times of war.
However, these codes could be listened into by anyone and therefore needed to be more complicated.
As technology improved, codes made by machines became popular because as these codes needed more complicated ciphers to decipher the messages.
One of the oldest decipher machines was the Alberti Disc, which used two discs on top of each other which would be turned to find the corresponding letter.
Alberti Disc

5. The Enigma Machine Ask what do you think this is? Left: Enigma machine
Right: Turing’s Bomb that broke the enigma code
One of the most famous cipher machines was the Enigma machine made by the Germans in the 1920s. This machine looked like a typewriter but each press of a button indicated a lighted letter. The machine used complex wiring and rotors to create a different letter each time. Without the cipher these machines were almost impossible to crack as they were using so many millions of
different letter combinations.
Context:
The Poles had broken Enigma in 1932, when the encoding machine was undergoing trials with the German Army. But, when the Poles broke Enigma, the cipher only altered once every few months. With the advent of war, it changed at least once a day, giving 159 million million million possible settings to choose from. The Poles decided to inform the British in July 1939 once they needed help to break Enigma and with invasion of Poland imminent.
The first operational break into Enigma came around the 23 January 1940, when the team of mathematicians John Jefferys, Peter Twinn & Alan Turing, unravelled the German Army administrative key that became known at Bletchley Park as ‘The Green’. Encouraged by this success, the Codebreakers managed to crack the ‘Red’ key used by the Luftwaffe liaison officers co-ordinating air support for army units. Gordon Welchman, soon to become head of the Army and Air Force section, devised a system whereby his Codebreakers were supported by other staff based in a neighbouring hut, who turned the deciphered messages into intelligence reports.

6. Alan Turing Gordon Welchman Who is this?
Left: Alan Turing, Right: Gordon Welchman
Alan Turing
Recently the film ‘The Imitation Game’ was based around the life and work of cryptanalyst Alan Turing, played by actor Benedict Cumberbatch. During World War II, mathematician Alan Turing tries to crack the enigma code with help from fellow mathematicians and eventually decrypted German intelligence codes for the British Government . Alan Turing created a new ‘Bombe machine’ – which managed to crack the Enigma machine, and make significant progress in the war. Alan Turing and his team of code breakers are credited with shortening the overall length of World War Two.
After World War Two, Prime Minister Churchill asked for the information relating to the discovery of the Enigma codes to be kept secret. Government
Codes & Ciphers School became the Government Communications Headquarters (GCHQ). Alan Turing was not recognised for his work, and due to his sexuality, was sentenced to be chemically castrated. He committed suicide in 1954 just before his 42nd birthday. In 2009 Prime Minister Gordon Brown apologised for the appalling treatment of Turing and in 2013 he was posthumously pardoned.
Gordon Welchman
Gordon Welchman also worked at Bletchley Park. He was a brilliant mathematician who worked alongside Alan Turing. While Alan Turing is linked to the successful cracking of the Enigma machine, Welchman’s role in the project is frequently overlooked. Welchman improved the Bombe – used in cracking code sent by Enigma – and made the machine a lot more efficient by increasing the speed with which each Bombe trawled through Enigma settings.

7. Located in Milton Keynes, Buckinghamshire, England and is now a heritage attraction.
Bletchley Park was the central site for Britain’s codebreakers during WWII. Run by the Government Code and Cypher School – it worked to crack secret communications – In particular, the German Enigma and Lorenz ciphers.
It was here where Alan Turing and his team, cracked the German Enigma and Lorenz code.
Because of the importance of code-breaking, Bletchley was Britain's ‘Top Secret’. Security was paramount and few outside of Bletchley knew its mission. All staff signed the Official Secrets Act (1939).
Historians claim that because of the intelligence at Bletchley Park – the war was shortened by 2-4 years, and the outcome of the war would have been uncertain.
Leading to the Cold War
A 1942 security warning emphasised the importance of discretion even within Bletchley itself: "Do not talk at meals. Do not talk in the transport. Do not talk travelling. Do not talk in the billet. Do not talk by your own fireside. Be careful even in your Hut ...“
In addition…
- Any commander in the field receiving ‘Ultra’ intelligence was fed a cover story crediting a non-’Ultra’ source.
- At times sham scouting missions – intentionally visible to the enemy – were dispatched to "discover" German positions in fact already known from Ultra. 
In some cases it was impossible to act on Ultra intelligence at all because to do so might suggest to the enemy that their communications had been penetrated.

8. Code Breakers in the COLD War
GCHQ, Mi5, Mi6 and their counterparts in America, the Central Intelligence Agency were very active in the Cold War attempting to uncover secrets transmitted and communicated between the USSR and its allies.
Intelligence gathering is now related to multiple aspects of their work, and the data gathered from both codes and satellites images led to the escalation in the Cold War of the Cuban missile crisis.
Mixed messages and a lack of clear communication resulted in some misunderstandings that could have potentially led to the end of the world as we know it.
The internet and ‘The Cloud’ that we use today are a result of the work that mathematicians like Gordon Welchman carried out during the Cold War.
Cryptographers and cryptanalysts still work to make and break codes but now have the ability to use complex computer programmes to assist. They would say that there is no unbreakable code, just codes that have yet to be broken.

9. CAN you Break The CODE? Rules:
Split the Class into two groups: USA & Soviet Union
Give students a list of codes to break for USA and codes to break for Soviet Union – using the Caesar cipher, whereby you replace letters with numbers or other letters.
The first one to break the code is responsible for saving the world
Give 10 minutes per code set.
If the codes are not broken within 10 minutes the President of the Soviet Union and the USA will launch Nuclear weapons and both teams lose.
Countdown clock link:
Ask:
Any problems that they faced as a team? How they worked together to break the codes?/ how they could improve their work in the future?
Possibly give clues to differentiate.

10. Create Your Own Code to conceal events during the CUbAn MISSILE CRISIS
19 Dec 1960: Cuba officially aligns itself with the Soviet Union following the severing of diplomatic ties and the embargo from the US.
17 Apr 1961: CIA backed Cuban exiles are defeated at the ‘Bay of Pigs’, after launching an invasion to overthrow the new Castro government.
27 July 1962: President Castro announces that any direct US attack on Cuba would result in the equivalent of a world war.
10 Aug 1962: CIA director informs President Kennedy that Soviet medium-range ballistic missiles will soon be deployed in Cuba.
14 Oct 1962: The US obtains photographic evidence of nuclear missiles stationed in western Cuba.
23 Oct 1962: President Kennedy orders US ships to form a ‘naval blockade’ to prevent the transportation of missiles.
26 Oct 1962: The US begins discussions about invading Cuba.
26 Oct 1962: President Khrushchev sends a letter to President Kennedy proposing to remove his missiles on the condition that the U.S never invade Cuba, and remove missiles threatening the Soviet Union from Turkey.
27 Oct 1962: A US spy plane gets lost and enters Soviet air space.
27 Oct 1962: President Kennedy agrees to President Khrushchev’s proposal and the removal of missiles stationed in Turkey.
28 Oct 1962: President Khrushchev announces over Radio Moscow that he has agreed to remove the missiles from Cuba.
Create Your Own Code to conceal events during the CUbAn MISSILE CRISIS
Your task: In teams, choose one of the Key events below and create a code and cipher for it.
Above is a brief Timeline of important events during the Cuban Missile Crisis.
Rules:
1) Staying in same US/Soviet union groups
2) Groups must choose one of the above key events during the Cuban Missile Crisis
3) Teams must have a cipher and a way of the code being decrypted when it reaches its destination.
4) At the end of the allotted time, students pass the codes to each other and try to break them out. They then create a code for it.

11. What do you think is the legacy of the code breakers in today’s world?
Do you think codes still exist?
How do you think codes can be used?
Are the use of codes a good thing?
What do they think could be some of the problems with secrecy and intelligence gathering?

12. QUESTIONS?