1. Alice decides to use the RSA cryptosystem to enable individuals to communicate secret in- formation to her. She chooses the public key (N, e) = (536813567, 3602561). Numerical plaintext is obtained from alphabetic plaintext in the following way. Plaintext blocks have 6 letters (in the standard 26-letter alphabet). Such an alphabetic block is then considered to be a 6-digit base-26 integer (where A represents 0, B represents 1, etc.). Ciphertext consists of 7-digit base-26 integers, which can also be considered as 7-character stings. (a) Suppose that Eve successfully cryptanalyzes this key. What decryption exponent d does she find? (b) Suppose Bob sends Alice the ciphertext BNBPPKZAVQZLBJ. Help Eve find the alpha- betic plaintext, for this message

1. Alice decides to use the RSA cryptosystem to enable individuals to communicate secret in- formation to her. She chooses the public key (N, e) = (536813567, 3602561). Numerical plaintext is obtained from alphabetic plaintext in the following way. Plaintext blocks have 6 letters (in the standard 26-letter alphabet). Such an alphabetic block is then considered to be a 6-digit base-26 integer (where A represents 0, B represents 1, etc.). Ciphertext consists of 7-digit base-26 integers, which can also be considered as 7-character stings. (a) Suppose that Eve successfully cryptanalyzes this key. What decryption exponent d does she find? (b) Suppose Bob sends Alice the ciphertext BNBPPKZAVQZLBJ. Help Eve find the alpha- betic plaintext, for this message

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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