In the past, encryption and decryption were mostly done by substitution and permutation of letters in a text message. study those classic cryptographic schemes Then, develop an automatic cipher using Javascript The cipher should be able to perform the following tasks: generate keys encrypt a given plaintext message with a key selected from the list of keys generated decrypt a given ciphertext message with a known cipher key

In the past, encryption and decryption were mostly done by substitution and permutation of letters in a text message. study those classic cryptographic schemes Then, develop an automatic cipher using Javascript The cipher should be able to perform the following tasks: generate keys encrypt a given plaintext message with a key selected from the list of keys generated decrypt a given ciphertext message with a known cipher key

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter8: Data And Network Communication Technology

Section: Chapter Questions

Problem 41VE

See similar textbooks

Similar questions

Cryptography problem mathematics Suppose Alice and Bob are using a cryptosystem with a 128-bit key, so there are 2128possible keys. Eve is trying a brute-force attack on the system.(a) Suppose it takes 1 day for Eve to try 264 possible keys. At this rate, how long willit take for Eve to try all 2128 keys? (b) Suppose Alice waits 10 years and then buys a computer that is 100 times fasterthan the one she now owns. Will she finish trying all 2128 keys before or after whatshe does in part (a)?
(Practice) Although the total number of bytes varies from computer to computer, memory sizes of millions and billions of bytes are common. In computer language, the letter M representsthe number 1,048,576, which is 2 raised to the 20th power, and G represents 1,073,741,824, which is 2 raised to the 30th power. Therefore, a memory size of 4 MB is really 4 times 1,048,576 (4,194,304 bytes), and a memory size of 2 GB is really 2 times 1,073,741,824 (2,147,483,648 bytes). Using this information, calculate the actual number of bytes in the following: a. A memory containing 512 MB b. A memory consisting of 512 MB words, where each word consists of 2 bytes c. A memory consisting of 512 MB words, where each word consists of 4 bytes d. A thumb drive that specifies 2 GB e. A disk that specifies 4 GB f. A disk that specifies 8 GB
In the ________, memory addresses consist of a single integer.
(For thought) a. A token of a computer language is any sequence of characters, with no intervening characters or white space, that taken as a unit has a unique meaning. Using this definition of a token, determine whether escape sequences, function names, and the keywords listed in Table 2.1 are tokens of the C++ language. b. Discuss whether adding white space to a message alters the message and whether messages can be considered tokens of C++. c. Using the definition of a token in Exercise 4a, determine whether the following statement is true: “Except for tokens of the language, C++ ignores all white space.”
One way to determine how healthy a person is by measuring the body fat of the person. The formulas to determine the body fat for female and male are as follows: Body fat formula for women: A1 = (body weight x 0.732) + 8.987 A2 = wrist measurement (at fullest point)/3.140 A3 = waist measurement (at navel) x 0.157 A4 = hip measurement (at fullest point) x 0.249 A6 = forearm measurement (at fullest point) x 0.434 B = A1 + A2 A3 A4 + A5 Body fat = body weight - B Body fat percentage = body fat x 100/body weight Body fat formula for men: A1 = (Body weight x 1.082) + 94.42 A2 = wrist measurement x 4.15 B = A1 A2 Body fat = body weight B Body fat percentage = body fat x 100/body weight Write a program to calculate the body fat of a person.