TAILIEUCHUNG - Lecture Data security and encryption - Lecture 4: Classical Encryption Techniques

This chapter presents the following content: Classical cipher techniques and terminology, brute force, cryptanalysis of brute force, caesar cipher, cryptanalysis of caesar cipher, monoalphabetic substitution ciphers, playfair cipher, polyalphabetic ciphers, vigenère cipher. | 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 # 4 Review classical cipher techniques and terminology Brute Force Cryptanalysis of Brute Force Caesar Cipher Cryptanalysis of Caesar Cipher Chapter 1 summary. Monoalphabetic Cipher With only 25 possible keys, the Caesar cipher is far from secure A dramatic increase in the key space can be achieved By allowing an arbitrary substitution, where the translation alphabet can be any permutation of the 26 alphabetic characters With only 25 possible keys, the Caesar cipher is far from secure. A dramatic increase in the key space can be achieved by allowing an arbitrary substitution, where the translation alphabet can be any permutation of the 26 alphabetic characters. A permutation of a finite set of elements S is an ordered sequence of all the elements of S, with each element appearing exactly once. In general, there are n! permutations of a set of n elements. See text example of a translation alphabet, and an encrypted message using it. Monoalphabetic Cipher A permutation of a finite set of elements S An ordered sequence of all the elements of S, with each element appearing exactly once. In general, there are n! permutations of a set of n elements. With only 25 possible keys, the Caesar cipher is far from secure. A dramatic increase in the key space can be achieved by allowing an arbitrary substitution, where the translation alphabet can be any permutation of the 26 alphabetic characters. A permutation of a finite set of elements S is an ordered sequence of all the elements of S, with each element appearing exactly once. In general, there are n! permutations of a set of n elements. See text example of a translation alphabet, and an encrypted message using it. Monoalphabetic .

• An ninh - Bảo mật
• Data security
• Data security and encryption
• Network security
• Symmetric ciphers
• Asymmetric ciphers
• Cryptographic data integrity algorithms
• Mutual trust
• Lecture Data security and encryption
• Mã hóa dữ liệu
• Bảo mật dữ liệu
• IPSec security framework
• IPSec security policy
• Wireless Network Security
• Wireless Application Protocol