1. mbizdyqbkzri k pkcmsxkdsxq rscdybi Atul Kahate www.atulkahate.com / akahate@gmail.com

2. Cryptography A Fascinating HistoryAtul Kahatewww.atulkahate.com / akahate@gmail.com 3. Three people can keep a secret if two of them are deadCrypto - A Fascinating History | Atul Kahate 3 4. Basic Principles SubstitutionTransposition Crypto - A Fascinating History | Atul Kahate 4 5. Persia Versus Greece(5th Century BC) Wooden tables Scratch the lower part, writemessages, cover with wax Crypto - A Fascinating History | Atul Kahate 5 6. Greeks and Waxing of Secret Messages Secret messages would be written as tattoosinto the shaven heads of messengers Crypto - A Fascinating History | Atul Kahate 6 7. SteganographySteganos = Covered, graphein = writing inGreekCrypto - A Fascinating History | Atul Kahate 7 8. Julius Caesar (100 BC-44 BC) Crypto - A Fascinating History | Atul Kahate 8 9. Queen Mary of Scotland (1542-1587) and Queen Elizabeth I of England (1533-1603)Crypto - A Fascinating History | Atul Kahate 9 10. Early Chinese Methods Write messages on fine silk and put that in atiny ball covered with wax messengerwould swallo itWrite in invisible inkCryptography Kryptos = Hidden in Greek Aim is not to hide the fact that there is a message, but the contents of a message Crypto - A Fascinating History | Atul Kahate 10 11. Leon Battista Alberti (1404-1472) Painter, Composer, Poet, Philosopher, AuthorCrypto - A Fascinating History | Atul Kahate 11 12. Blaise de Vigenere (1523-1596) French diplomat and cryptographer See next slideCrypto - A Fascinating History | Atul Kahate 12 13. Vigenere Square Example1.Draw a Vigenere square (previous slide) 2.Top row represents the plain text letter and columns indicate key look for the cross-section 3.Replace it with the cipher text letter from the square based on the key Example: Message is divert troops and key is white then encryption would be: Key :whitew Plaintext :dIvert Ciphertext : zpdxvp Crypto - A Fascinating History | Atul Kahate 13 14. Charles Babbage (1791-1871) Broke Vigenere Cipher Difference and Analytical EnginesCrypto - A Fascinating History | Atul Kahate 14 15. Lovers and Newspapers Encrypted messages to each other viapersonal columns in the newspapers calledas agony columns Babbage along with his friend Charles Wheatstone Oxford student incident involving Wheatstone in The TimesNewspapers were posted for free in thosedays people would use pinpricks to secretlyadd messages Crypto - A Fascinating History | Atul Kahate 15 16. USA Independence Struggle (1770s) Benjamin ChurchGeorge Washington Crypto - A Fascinating History | Atul Kahate 16 17. Telegraph More need for Secrecy! Morse (1791-1872) and Wheatstone (1802-1875)Crypto - A Fascinating History | Atul Kahate 17 18. Wireless! Galvini, Volta, Orsted, Faraday, Ampere, Henry, Maxwell, Lodge Crypto - A Fascinating History | Atul Kahate 18 19. Wireless! Hertz, MarconiCrypto - A Fascinating History | Atul Kahate 19 20. First World War 1917 Germany, Planned attack on Britishnaval base, Fear of attacking American shipsby mistake, German Foreign Minister ArthurZimmermann planned to forge an alliancewith Mexico to help recapture lost territory Crypto - A Fascinating History | Atul Kahate 20 21. The Famous Telegram Crypto - A Fascinating History | Atul Kahate 21 22. Enigma 1918 Scherbius & Ritter - Company formedby German inventor Arthur Scherbius and hisfriend Richard Ritter Crypto - A Fascinating History | Atul Kahate 22 23. Hans-Thilo Schmidt (1888-1943) German soldier in The First World War,Rejected in the Second one, disgruntled,Soap factory failure, Hyperinflation, Elderbrother Rudolph in Army authorized Enigma,Further anger, Sold Enigma papers for10,000 Marks Crypto - A Fascinating History | Atul Kahate 23 24. Breaking Enigma in the Second World War Marian Rejewski (1905-1980)Polish mathematician Timid Fled toEngland after Germany attacked Poland 1932 Started working on breaking EnigmaCrypto - A Fascinating History | Atul Kahate 24 25. Bletchley Park Alan Turing (1912-1954)Crypto - A Fascinating History | Atul Kahate 25 26. Navajo Code TalkersCrypto - A Fascinating History | Atul Kahate 26 27. DES 1975 Horst Fiestel (1915-1990) and Lucifer Crypto - A Fascinating History | Atul Kahate 27 28. Public Key Cryptography - Whitfield Diffie (1944 -) and Martin Hellman (1945 -)With Merkel here Crypto - A Fascinating History | Atul Kahate 28 29. RSARon Rivest (1947 -), Adi Shamir (1952 -), and Len Adleman(1945 -) Crypto - A Fascinating History | Atul Kahate 29 30. Jim BidzosCrypto - A Fascinating History | Atul Kahate 30 31. Secure Email Phil ZimmermanCrypto - A Fascinating History | Atul Kahate 31 32. VGhhbmsgWW91IFZlcnkgT XVjaCE= QW55IFF1ZXN0aW9ucyBvciBDb21tZW50cz8= 33. Thank You Very Much!Any Questions or Comments? www.atulkahate.com / akahate@gmail.com