I NTRODUCTION TO C RYPTOLOGY Cryptoanalysts, Encryption, and Decryption

W HAT IS C RYPTOGRAPHY / C RYPTOLOGY The art of protecting information by transforming it ( encrypting it) into an unreadable format, called cipher text. encryptingcipher text Only those who possess a secret key can decipher (or decrypt ) the message into plain text. decryptplain text Encrypted messages can sometimes be broken by cryptanalysis, also called codebreaking, although modern cryptography techniques are virtually unbreakable. ETPRO 2010

H OW DO YOU THINK THIS CODE WAS ENCRYPTED ? ETPRO 2010

T HIS IS C IPHER TEXT Cipher text Text that has been transformed into an unreadable format. Code In cryptology, code means substituting a meaningful word or phrase with another word or phrase to change or hide meaning ETPRO 2010

H OW C OULD YOU SOLVE THIS C IPHER ? ETPRO 2010

D ID YOU KNOW THAT SOME LETTERS IN THE ALPHABET OCCUR MORE FREQUENTLY IN THE E NGLISH LANGUAGE ? ETPRO 2010

S OLVE THE C IPHER ETPRO 2010

S OLUTION : W HAT IS THE KEY ? A key is symbols, characters, or letters required by the algorithm to encrypt or decrypt a message = today = you = will = learn = about = codes (and ciphers) ETPRO 2010

M ETHODS OF C RYPTOGRAPHY Substitution Replacing each letter with a different letter or symbol b=J, c=2 so that “a cat” = Transposition Rearranging the order of letters of the words of a message. (example: “the letters in each word get moved around = eth ttseelr ni ceah drow etg veodm uarndo”) Steganography Hiding a message (example: invisible inks, Herodotus tattooed messages on a shaved slave’s head and waited for the hair to re-grow to hide his messages) Mathematical Uses advanced formulas to encrypt text Computer or Mechanically Assisted Using complex algorithms and any single or combination of the mathematical, transposition, substitution and steganography to encrypt plain text. ETPRO 2010

T HE E NIGMA M ACHINE The most famous mechanical encryption device in history. ETPRO 2010

W HO THINKS UP THIS STUFF ? Cryptanalyst: Job Description The scientist responsible for creating algorithms for transforming plain text into unreadable information (cipher text), or for decrypting encrypted information AKA Cryptographer, Cryptologic Technician, Cryptologic Linguist, Symbolist, Decipherer, Information Security Expert, Intelligence Agent or Officer, Information Security Engineer Salary Range  $55,000 - $130,000 and more! Education Required  Entry level: Undergraduate: Math, Computer Science, foreign languages, engineering, telecommunications, computer programming languages, political science and/or relations  Mid and High Level Jobs: Graduate: Masters’ or PHD in Cryptology, Mathematics  National Security Agency provides internships  Additional Skills L INGUISTICS, S UBJECT KNOWLEDGE, R ESEARCH (R ESOURCE : HTTP :// CAREERSTHATDONTSUCK. COM /2007/02/24/ C AREER - PROFILE - CRYPTOLOGIST /) HTTP :// CAREERSTHATDONTSUCK. COM /2007/02/24/ C AREER - PROFILE - CRYPTOLOGIST / ETPRO 2010

W HY DO WE NEED C RYPTANALYSTS Copyright Protection Security of communications for Personal Businesses Government Military Credit Card Processing Password Protection RSA tokens: for business and games (like Warcraft) ETPRO 2010

L EGAL P ROBLEMS FOR C RYPTANALYSTS Digital Millennium Copyright Act (1998) Intended to provide law enforcement with a tool to go after piracy and file sharing (media like music, movies, and software) Made it illegal to use cryptanalytic techniques to get around the copyright protection methods (called Digital Rights Management ) Unintended result was to limit research and research sharing in the Cryptanalyst field for fear that their work might violate this law. Cryptanalyst argue that the algorithms should be published so that they can be improved and used. Only the keys should remain a secret. The first arrest was Dmitry Sklyarov, whose dissertation work and subsequent work with a Russian book reader company identified weaknesses in the protection of PDF files. ETPRO 2010

Y OU ARE THE C RYPTANALYST ! Create your own algorithm for encrypting a message! Substitution Replacing each letter with a different letter or symbol b=J, c=2 so that “a cat” = Transposition Rearranging the order of letters of the words of a message. (example: “the letters in each word get moved around = eth ttseelr ni ceah drow etg veodm uarndo”) Steganography Hiding a message (example: invisible inks, Herodotus tattooed messages on a shaved slave’s head and waited for the hair to re-grow to hide his messages) Mathematical Uses advanced formulas to encrypt text Computer or Mechanically Assisted Using complex algorithms and any single or combination of the mathematical, transposition, substitution and steganography to encrypt plain text. ETPRO 2010