(a) The following message was encoded using an affine cryptosystem that encodes A as M and B as B. CKMYCZMLCOCWKOHUCKDOHLMZLLNMZGZOEVUFYU Find the plaintext. (b) The following message was encoded using an affine cryptosystem that encodes A as G and C as C. MQTNOELNWNETEHCEWHISCFKYHHFYKGCCEIPXQWFISCF Find the plaintext. (c) The following message was encoded using an affine cryptosystem that encodes R as S and S as D. OMFMFNSOMNDSFNDLADOMNOSFNDLAJNAALOZAUFSDONAU Find the plaintext.

(a) The following message was encoded using an affine cryptosystem that encodes A as M and B as B. CKMYCZMLCOCWKOHUCKDOHLMZLLNMZGZOEVUFYU Find the plaintext. (b) The following message was encoded using an affine cryptosystem that encodes A as G and C as C. MQTNOELNWNETEHCEWHISCFKYHHFYKGCCEIPXQWFISCF Find the plaintext. (c) The following message was encoded using an affine cryptosystem that encodes R as S and S as D. OMFMFNSOMNDSFNDLADOMNOSFNDLAJNAALOZAUFSDONAU Find the plaintext.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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A symmetric block encryption algorithm is shown below. 16-bit blocks of plaintext P are encrypted using a 32-bit key. Encryption is defined as: C = (P EX_OR Ko) + K1 C is the ciphertext, K is the secret key, Ko is the leftmost 16 bits of K, K1 is the rightmost 16 bits of K, EX_OR is bitwise exclusive OR, and + is binary addition. a. The ciphertext C must be the same size as the plaintext P, that is, it must not be larger than 16 bits. How can this be achieved? b. Show the decryption equation. How will the encrypted message be decrypted?
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The Caesar Cipher Algorithm was introduced in Week #1. Encryption is the act of encoding a message with the intent of allowing only authorized people the knowledge of how to read that message. An encrypted message can be decoded, allowing the secured content to be read after decryption. Recall that the Caesar Cipher uses alphabets as the primary source of information but shifted a certain number of letters to the left or right as a key to create the encrypted data. The Caesar Cipher is easily hacked because of the simple technique used to build the key that encrypts and decrypts the data. In this lab, the key is the number of alphabets shifted, and the direction is always toward the increasing alphabetical order. This provides 26 ways of encrypting a message and therefore makes it easier to be hacked by guessing the key within the range of 0 - 25. Write the function caesar_hack( ) that takes three parameters: a Caesar Cipher encrypted message, an alphabet list, and the original…