EBK COMPUTER NETWORKING
7th Edition
ISBN: 8220102955479
Author: Ross
Publisher: PEARSON
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Question
Chapter 8, Problem P6P
a)
Program Plan Intro
Block Cipher:
A Block Cipher is a method of encrypting text in which a cryptographic key and
Given Information:
It is given that there is a three bit block cipher. The given plaintext is “100100100”.
b)
Program Plan Intro
Block Cipher:
A Block Cipher is a method of encrypting text in which a cryptographic key and algorithm are applied to blocks of data.
Given Information:
It is given that there is a three bit block cipher. The given plaintext is “100100100”.
c)
Program Plan Intro
Block Cipher:
A Block Cipher is a method of encrypting text in which a cryptographic key and algorithm are applied to blocks of data.
XOR Truth table:
The XOR gate follows the following truth table:
| A | B | A XOR B |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
Given Information:
It is given that there is a three bit block cipher. The given plaintext is “100100100”.
Now suppose that CBC is used with IV = 111.
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Students have asked these similar questions
The definition of a Shift Cipher can be expressed as follows:Def. Let x, y, k ∈ Z26 with the encryption operation as ek(x) ≡ x + k mod 26 and thedecryption operation as dk(y) ≡ y - k mod 26.Given the provided letter encoding, what would be the encoding of the plaintext word ATTACKafter applying a shift cipher with a k=17?
Question 3
The definition of a Shift Cipher can be expressed as follows:Def. Let x, y, k ∈ Z26 with the encryption operation as ek(x) ≡ x + k mod 26 and the decryption operation as dk(y) ≡ y - k mod 26.Given the provided letter encoding, what would be the encoding of the plaintext word ATTACK after applying a shift cipher with a k=17?
Consider a homophonic cipher in which H(A) = {000, 001, 101, 011} and H(B) = {111, 110, 010, 100}.
What is the plaintext that results from the decryption of 110000100011?
Answer:
Chapter 8 Solutions
EBK COMPUTER NETWORKING
Ch. 8 - Prob. R1RQCh. 8 - Prob. R2RQCh. 8 - Prob. R3RQCh. 8 - Prob. R4RQCh. 8 - Prob. R5RQCh. 8 - Prob. R6RQCh. 8 - Prob. R7RQCh. 8 - Prob. R8RQCh. 8 - Prob. R9RQCh. 8 - Prob. R10RQ
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