Given a plaintext in HEX P1=AE1C, the encrypted cipher text is C1=87D2 with key K through stream cipher. Another Cipher text C2=6FF1 is encrypted by the same key K from P2 through stream cipher. Please decrypt the plaintext P2. You should transfer HEX to Binary number then calculate.(Use the property of XOR, don't calculate the key K

Given a plaintext in HEX P1=AE1C, the encrypted cipher text is C1=87D2 with key K through stream cipher. Another Cipher text C2=6FF1 is encrypted by the same key K from P2 through stream cipher. Please decrypt the plaintext P2. You should transfer HEX to Binary number then calculate.(Use the property of XOR, don't calculate the key K

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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In a substitution cipher, we “encrypt” (i.e., conceal in a reversible way) a message by replacing every letter with another letter. To do so, we use a key: in this case, a mapping of each of the letters of the alphabet to the letter it should correspond to when we encrypt it. To “decrypt” the message, the receiver of the message would need to know the key, so that they can reverse the process: translating the encrypt text (generally called ciphertext) back into the original message (generally called plaintext). A key, for example, might be the string NQXPOMAFTRHLZGECYJIUWSKDVB. This 26-character key means that A (the first letter of the alphabet) should be converted into N (the first character of the key), B (the second letter of the alphabet) should be converted into Q (the second character of the key), and so forth. A message like HELLO, then, would be encrypted as FOLLE, replacing each of the letters according to the mapping determined by the key. Let’s write a program called hw6.py…
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