A secure email system is expected to provide confidentiality, sender's non-repudiation, and message integrity. Alice uses three keys to achieve this goal. The three keys are Alice's private key (KA), Bob's public key (KB+), and a randomly generated symmetric key (Ks). The encryption procedure is shown below: How can Bob 1) decrypt the data, 2) verify the message's integrity, and 3) verify the sender's non- repudiation? Describe the detailed steps (including the formulas) and show your work. KA m➡ HO KA m I am using SHA-256 KA(H(M)) + Ks Ks() + KB(*) Ks Ks(m, KA(H(m)) + + KB(KS) Internet

A secure email system is expected to provide confidentiality, sender's non-repudiation, and message integrity. Alice uses three keys to achieve this goal. The three keys are Alice's private key (KA), Bob's public key (KB+), and a randomly generated symmetric key (Ks). The encryption procedure is shown below: How can Bob 1) decrypt the data, 2) verify the message's integrity, and 3) verify the sender's non- repudiation? Describe the detailed steps (including the formulas) and show your work. KA m➡ HO KA m I am using SHA-256 KA(H(M)) + Ks Ks() + KB(*) Ks Ks(m, KA(H(m)) + + KB(KS) Internet

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 secure email system is expected to provide confidentiality, sender's non-repudiation, and message integrity. Alice uses three keys to achieve this goal. The three keys are Alice's private key (KA), Bob's public key (Kg), and a randomly generated symmetric key (Ks). The encryption procedure is shown below: How can Bob 1) decrypt the data, 2) verify the message's integrity, and 3) verify the sender's non-repudiation? Describe the detailed steps (including the formulas) and show your work. KA m H(-) KA( m I am using SHA-256 KA(H(M)) Ks() KB(*) K Ks K.(m, KA(H(m)) + + KB(Ks) Internet 34
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5. Use RSA public-key encryption to decrypt the message 111 using the private keys n = 133 and d = 5.
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