logging in or signing up Secret Codes VC1 Justine Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 314 Category: Entertainment License: All Rights Reserved Like it (1) Dislike it (0) Added: January 01, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Slide1: The Secret World of Codes and Codebreaking The enigma projectSlide2: Plaintext: normal English Ciphertext: coded English Code: whole words or phases are replaced by a letter or number Cipher: individual letters are replaced with other letters or symbols Slide3: ACTIVITY 1 Decipher the ciphertext on the strip of paper. CLUE: You will have to use a pencil. But you don’t use the pencil in the usual way!Slide4: Scytale: Used by the Spartans in Ancient Greece 2500 years agoSlide5: Scytales must be the same size to be able to decipher a messageSlide6: Scytales must be the same size to be able to decipher a messageSlide7: Cipher = Algorithm + Key Slide9: Caesar Shift Cipher MISS ELLIS NJTT FMMJTSlide10: Caesar Shift Cipher MXOLXV FDHVDU WKH URPDQ JHHCHU VTXDVKHG KLV ZLIH LQ D OHPRQ VTXHHCHUSlide11: Decipher this message. Each plaintext letter has been moved three places forward in the alphabet… MXOLXV FDHVDU WKH URPDQ JHHCHU VTXDVKHG KLV ZLIH LQ D OHPRQ VTXHHCHU ACTIVITY 2 7K H P J Slide12: Caesar Shift Cipher Julius Caesar the Roman Geezer Squashed his wife in A Lemon Squeezer!Slide13: Caesar Shift Cipher How many possible keys are there with the Caesar Shift Cipher? 25Slide14: How many possible keys are there when you swap each letter of the alphabet with another letter? 400 million billion billion 400 000 000 000 000 000 000 000 000 ACTIVITY 3Slide15: 400 million billion billion keys 6.5 billion people in the world 31 million seconds in a year If everyone in the world checked one key per second, it would still take 2 billion years to check them allSlide16: Mary Queen of Scots and the Babington PlotSlide17: One of the messages Mary Queen of Scots sent to BabingtonSlide18: ACTIVITY 4 How would you go about trying to crack this type of cipher when there are a possible 400 million billion billion keys?Slide19: Today, by radio, and also on giant hoardings, a rabbi, an admiral notorious for his links to masonry, a trio of cardinals and a trio, too, of politicians inform us all of how our country now risks dying of starvation. An unusual messageSlide20: START NOW STOP! ACTIVITY 5 Have a conversation with the person sitting next to you WITHOUT using any words that contain the letter ESlide21: Al Kindi’s book written in 800 ADSlide22: Code Breaking Tips Common letters One letter words Common words Double letters CluesSlide23: WW2 Enigma MachineSlide24: General Guderian’s Command-post vehicleSlide27: Bletchley Park – Government Code and Cipher School You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Secret Codes VC1 Justine Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 314 Category: Entertainment License: All Rights Reserved Like it (1) Dislike it (0) Added: January 01, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Slide1: The Secret World of Codes and Codebreaking The enigma projectSlide2: Plaintext: normal English Ciphertext: coded English Code: whole words or phases are replaced by a letter or number Cipher: individual letters are replaced with other letters or symbols Slide3: ACTIVITY 1 Decipher the ciphertext on the strip of paper. CLUE: You will have to use a pencil. But you don’t use the pencil in the usual way!Slide4: Scytale: Used by the Spartans in Ancient Greece 2500 years agoSlide5: Scytales must be the same size to be able to decipher a messageSlide6: Scytales must be the same size to be able to decipher a messageSlide7: Cipher = Algorithm + Key Slide9: Caesar Shift Cipher MISS ELLIS NJTT FMMJTSlide10: Caesar Shift Cipher MXOLXV FDHVDU WKH URPDQ JHHCHU VTXDVKHG KLV ZLIH LQ D OHPRQ VTXHHCHUSlide11: Decipher this message. Each plaintext letter has been moved three places forward in the alphabet… MXOLXV FDHVDU WKH URPDQ JHHCHU VTXDVKHG KLV ZLIH LQ D OHPRQ VTXHHCHU ACTIVITY 2 7K H P J Slide12: Caesar Shift Cipher Julius Caesar the Roman Geezer Squashed his wife in A Lemon Squeezer!Slide13: Caesar Shift Cipher How many possible keys are there with the Caesar Shift Cipher? 25Slide14: How many possible keys are there when you swap each letter of the alphabet with another letter? 400 million billion billion 400 000 000 000 000 000 000 000 000 ACTIVITY 3Slide15: 400 million billion billion keys 6.5 billion people in the world 31 million seconds in a year If everyone in the world checked one key per second, it would still take 2 billion years to check them allSlide16: Mary Queen of Scots and the Babington PlotSlide17: One of the messages Mary Queen of Scots sent to BabingtonSlide18: ACTIVITY 4 How would you go about trying to crack this type of cipher when there are a possible 400 million billion billion keys?Slide19: Today, by radio, and also on giant hoardings, a rabbi, an admiral notorious for his links to masonry, a trio of cardinals and a trio, too, of politicians inform us all of how our country now risks dying of starvation. An unusual messageSlide20: START NOW STOP! ACTIVITY 5 Have a conversation with the person sitting next to you WITHOUT using any words that contain the letter ESlide21: Al Kindi’s book written in 800 ADSlide22: Code Breaking Tips Common letters One letter words Common words Double letters CluesSlide23: WW2 Enigma MachineSlide24: General Guderian’s Command-post vehicleSlide27: Bletchley Park – Government Code and Cipher School