tailieunhanh - Hacker Professional Ebook part 155

Tham khảo tài liệu 'hacker professional ebook part 155', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 22 16 AV SYN 54 36 6 86 56 V 118 76 v 23 17 aw ETB 55 37 7 87 57 W 119 77 w 24 18 ax CAN 56 38 8 88 58 X 120 78 x 25 19 ay EM 57 39 9 89 59 Y 121 79 y 26 1a az SUB 58 3a 90 5a Z 122 7a z 27 1b a ESC 59 3b 91 5b 123 7b 28 1c a FS 60 3c 92 5c 124 7c 29 1d a GS 61 3d 93 5d 125 7d 30 1e aa rs 62 3e 94 5e a 126 7e 31 1f a_ US 63 3f 95 5f 127 7f DEL Associative A dyadic operation in which two sequential operations on three arguments can first operate on either the first two or the last two arguments producing the same result in either case a b c a b c . Also see commutative and distributive. Asymmetric Cipher A public key cipher. Attack General ways in which a cryptanalyst may try to break or penetrate the secrecy of a cipher. These are not algorithms they are just approaches as a starting place for constructing specific algorithms. Classically attacks were neither named nor classified there was just here is a cipher and here is the attack. And while this gradually developed into named attacks there is no overall attack taxonomy. Currently attacks are often classified by the information available to the attacker or constraints on the attack and then by strategies which use the available information. Not only ciphers but also cryptographic hash functions can be attacked generally with very different strategies. Informational Constraints We are to attack a cipher which enciphers plaintext into ciphertext or deciphers the opposite way under control of a key. The available information necessarily constrains our attack strategies. Ciphertext Only We have only ciphertext to work with. Sometimes the statistics of the ciphertext provide insight and can lead to a break. Known Plaintext We have some or even an extremely large amount of plaintext and the associated ciphertext. Defined Plaintext We can submit arbitrary messages to be ciphered and capture the resulting ciphertext. Also Chosen Plaintext and Adaptive Chosen Plaintext. Defined Ciphertext We can submit arbitrary messages