Consider a very simple symmetric block encryption algorithm in which 32-bits blocks of plaintext are encrypted using a 64-bit key. Encryption is defined as C = (P + Ko) K₁ where C = ciphertext, K = secret key, Ko = leftmost 64 bits of K, K₁ = rightmost 64 bits of K. = bitwise exclusive OR, and is addition mod 264. a. Show the decryption equation. That is, show the equation for P as a function of C, Ko, and K₁. b. Suppose and adversary has access to two sets of plaintexts and their correspond- ing ciphertexts and wishes to determine K. We have the two equations: C = (PK) K₁; C = (PK) K₁ First, derive an equation in one unknown (e.g., Ko). Is it possible to proceed fur- ther to solve for Ko?

Consider a very simple symmetric block encryption algorithm in which 32-bits blocks of plaintext are encrypted using a 64-bit key. Encryption is defined as C = (P + Ko) K₁ where C = ciphertext, K = secret key, Ko = leftmost 64 bits of K, K₁ = rightmost 64 bits of K. = bitwise exclusive OR, and is addition mod 264. a. Show the decryption equation. That is, show the equation for P as a function of C, Ko, and K₁. b. Suppose and adversary has access to two sets of plaintexts and their correspond- ing ciphertexts and wishes to determine K. We have the two equations: C = (PK) K₁; C = (PK) K₁ First, derive an equation in one unknown (e.g., Ko). Is it possible to proceed fur- ther to solve for Ko?

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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Problems are on this Textbook: Stallings, W. (2019). Cryptography and Network Security (8/E). Pearson Publishing. ISBN: 978-0-13576-403-9 7.10 In discussing the CTR mode, it was mentioned that if any plaintext blocks that is encrypted data using a given counter value is known, then the output of the encryption function can be determined easily from the associated cipher text block. SHow the calculation.
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For this problem you will perform RSA encryption and decryption with p = 13, q = 17, and e = 5 (not 3!). Show your work. Compute n and d. Encrypt the message m = 14 and give the ciphertext. Perform decryption on the ciphertext obtained in part (b) to get the plaintext message.
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Let the input size of a block cipher be 16 bits and the block cipher is used in the electronic code book (ECB) mode of operation. Suppose we have the following plaintext where all blocks are encrypted using the same key: (02 34 67 88 02 34 44 AB 67 88 B0 3F)hex i) Let say the encrypted important file is stored in this scheme and each data record has a size of 16 bits. The records are not related to one another. Is ECB mode still appropriate in this scenario? Please state your reason.
2. Show the encryption/decryption diagram for RSA algorithm by considering the following: plaintext= 3314, ciphertext=10260, public key (PU)={11, 11023}, private key={5891, 11023} please everything hand drawn and hand writen
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Alice and Bod have decided to use a symmetric encryption algorithm. They have someassumptions about their messages:- Messages only contain capital letters (i.e. A to Z)- The length of their shared key must be greater than or equal to the length of the plaintext- They assign each letter a number as follows: (A,0), (B,1), (C,2), (D,3),…, (Z,25)Their algorithm combines the key and the message using modular addition. The numerical valuesof corresponding message and key letters are added together, modulo 26. For example, if the plaintext is “HELLO” and the key is “SECRET” then the encrypted message is calculated as following:Since the length of the plaintext is 5, we just need the first 5 letters of the key (i.e. “SECRE”), thenfor each letter, we should add corresponding letters in both the plaintext and the key modulo 26.Plaintext: H (7) E (4) L (11) L (11) O (14)Key: S (18) E (4) C (2) R (17) E(4)Cipher: Z (25) I (8) N(13) C(2) S (18) a) Write a program in Python, C/C++ or JavaScript to…