PairashThajchayapong1

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Published on January 2, 2008

Author: Javier

Source: authorstream.com

Slide1:  GCIO Intensive Training Course jointly managed by Office of the Civil Servant Commission (OCSC) Ministry of Information and Communication Technology (MICT) Ministry of Science and Technology( MOST) Launched in Sep 1998 a special 30-hour/2 week in compulsory training program 19 CIO intensive training courses have been carried out 684 CIOs have completed the courses 280 CIOs are playing their role right now CIO Training Course The Caesar cipher:  The Caesar cipher 50 - 60 B.C. - Julius Caesar Julius Caesar's simple substitution cipher. This type of encryption is one of the simplest and most widely known encryption techniques. Each letter of the plaintext is replaced by a letter some fixed number of positions further down the alphabet. For example, a shift of 4 would move A to E, B to F, etc. such as: Plain: abcdefghijklmnopqrstuvwxyz Cipher: DEFGHIJKLMNOPQRSTUVWXYZABC The Caesar cipher is named after Julius Caesar, who, according to Suetonius, used it with a shift of three to protect messages of military significance. Slide3:  1587 - Mary Queen of Scots Mary Queen of Scots was beheaded for plotting against Queen Elizabeth using mono-alphabetic substitution ciphers. Mary was condemned on the basis of evidence obtained from enciphered messages cracked by Tomas Phelippes. Phelippes was able to crack a cipher used by Mary and conspirators who wanted to place her on the English throne, even though the cipher contained nulls and codewords. Mary Queen of Scots Enigma:  Enigma 1918 - The Enigma Arthur Scherbius designed the Enigma - a device which allowed businesses to communicate confidential documents without having to resort to clumsy and slow codebooks. The device consisted of many rotors turning on a common axis. The rotors had numbers 1 through 26 marked on the edge, or the alphabet A-Z, and were equipped with 26 electrical contacts (one for each letter of the alphabet) so that when a letter was pressed, the output would depend on the position of the rotor and its cross wiring. Within the same year, the Enigma was put to use; most famously by Nazi Germany before and during WWII. Slide5:  1971 - Lucifer Horst Feistel created Lucifer at IBM's Thomas J. Watson Laboratory. Lucifer was the name given to several of the earliest civilian block ciphers and was a direct precursor to the Data Encryption Standard(DES). Lucifer: Symmetric Key Horst Feistel Slide6:  1976 - Diffie & Hellman Whitfield Diffie & Martin Hellman publishPublic-key Cryptography. This asymmetric key cryptosystem was known as the Diffie-Hellman key exchange. It was the first published practical method for establishing a secret key through unprotected communications channels without a prior shared secret. Birth of Public Key Merkle,Hellman and Diffie Rivest,Shamir and Adleman:  Rivest,Shamir and Adleman 1977-RSA Algorithm Prime Number 1,3,5,7,11, etc Modular function f(x) = yx(modp) Slide8:  Confidentiality (encrypt/decrypt) Authentication Integrity Non-repudiation (digital signature) Internet Era

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