tailieunhanh - Lecture Data security and encryption - Lecture 13: Block Cipher Operation

The contents of this chapter include all of the following: multiple encryption & DES, why not double-DES? triple-DES with two-keys, modes of operation, electronic codebook book (ECB), advantages and limitations of ECB, cipher block chaining (CBC). | Data Security and Encryption (CSE348) Lecture slides by Lawrie Brown for “Cryptography and Network Security”, 5/e, by William Stallings, briefly reviewing the text outline from Ch 0, and then presenting the content from Chapter 1 – “Introduction”. Lecture # 13 Review have considered: Group Ring Field finite fields GF(p) polynomial arithmetic in general and in GF(2n) Chapter 4 summary. Chapter 6 – Block Cipher Operation Opening quote. 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 + Opening quote. Multiple Encryption & DES Given the potential vulnerability of DES to a brute-force attack There has been considerable interest in finding an alternative One approach is to design a completely new algorithm, of which AES is a prime example Given the potential vulnerability of DES to a brute-force attack,there has been considerable interest in finding an alternative. One approach is to design a completely new algorithm, of which AES is a prime example. Another alternative, which would preserve the existing investment in software and equipment, is to use multiple encryption with DES and multiple keys. We examine the widely accepted triple DES (3DES) approach. Multiple Encryption & DES Another alternative, which would preserve the existing investment in software and equipment To use multiple encryption with DES and multiple keys Widely accepted triple DES (3DES) approach is examined Given the potential vulnerability of DES to a brute-force attack,there has been considerable interest in finding an alternative. One approach is to design a completely new algorithm, of which AES is a prime example. Another alternative, which would preserve the existing investment in software and . | Data Security and Encryption (CSE348) Lecture slides by Lawrie Brown for “Cryptography and Network Security”, 5/e, by William Stallings, briefly reviewing the text outline from Ch 0, and then presenting the content from Chapter 1 – “Introduction”. Lecture # 13 Review have considered: Group Ring Field finite fields GF(p) polynomial arithmetic in general and in GF(2n) Chapter 4 summary. Chapter 6 – Block Cipher Operation Opening quote. 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 + Opening quote. Multiple Encryption & DES Given the potential vulnerability of DES to a brute-force attack There has been considerable interest in finding an alternative One approach is to design a completely new algorithm, of which AES