密码学的演变历史1课件.ppt

2007-5-11 Cryptography and Network Security - 2 Cryptography and Network SecurityChapter 2 Classical Encryption Techniques Fourth Edition by William Stallings Lecture slides by 杨寿保 syang@ 1/~syang/cryptoclass September 2008 Part One–Symmetric Ciphers Road Map for Part One Chp.2, Classical Encryption Techniques Chp.3, Block Cipher and the Data Encryption Standard Chp.4, Finite Fields Chp.5, Advanced Encryption Standard Chp.6, More on Symmetric Ciphers Chp.7, Confidentiality Using Symmetric Encryption Chapter 2 – Classical Encryption Techniques Many savages at the present day regard their names as vital parts of themselves, and therefore take great pains to conceal their real names, lest these should give to evil-disposed persons a handle by which to injure their owners. —The Golden Bough, Sir James George Frazer 密码学的演变历史(1) 1918, William Friedman’s The Index of Coincidence and its Applications in Cryptography Edward Hebern, Rotor Machine for 50 Years. 1949, Claude Shannon’s The Communication Theory of Secrecy System, 成为理论基础 1949-1967，Cryptographic Literature was barren 1971, IBM: Luciffer Cipher, 128位密钥作分组加密 by team led by Horst Feistel used 64-bit data blocks with 128-bit key 1975, Diffie-Hellman, A New Direction in Cryptography, 首次提出适应网络必威体育官网网址通信的公开密钥思想，揭开现代密码学研究的序幕，具有划时代的意义 1976-1977，美国国家标准局正式公布实施DES，Data Encryption Standard 密码学的演变历史(2) 1977－1978，Rivest, Shamir, Adelman 第一次提出公开密钥密码系统的实现方法RSA 1981，成立International Association for Cryptology Research 1985，ElGamal 提出概率密码系统 ElGamal方法 1990－1992，Lai Xuejia and James: IDEA, The International Data Encryption Algorithm 2000, AES, Advanced Encryption Standard 密码学基本术语 Terminologies Cryptology(必威体育官网网址学)，源自希腊语(Greek) Kryptós: hidden; logos: word, 是密码学和密码处理过程的研究。 Cryptography: The Science and Study of Secret Writing，密码编码学 Cryptanalysis: The Science and Study of Secret Breaking，密码破译学 Cipher: A secret method of writing 加密方法 Encipher (encipherment), encryption: 将明文转换成密文的过程 Decipher (decipherment), decryption: 将密文还原成明文的过程 Plaintext