2Questions2.1 Q1For this question, every encryption scheme satisfies complete correctness.Security is for a single message.2.1.1ALet h1, h2 be negligible functions (that are never equal to zero). Prove ordisprove:1. 1 is negligible as well.2. h1 · h2 is negligible as well.2.1.2 ВWe will define a variation of OTP with a key length k = k||k2 where |k1| =|k2| and M = C = {0,1}10, K = 0, 120. The encryption function :Enc(k = k1||k2, m) = m k1 e k2Complete the decryption algorithm. Prove that the scheme satisfies per-fect correctness and perfect secrecy.2.1.3We will define a variation of OTP with M = {0, 1}10, C = {0, 1}1', K =0,110 Where the encryption algorithm is defined as:{ (me k, 1)(т,0)if k ¢ {0lº, 1º}Enc(k, m)otherwise2Complete the decryption algorithm. Specify for which e the scheme sat-isfies e statistical security. Prove it is the correct e.

In questions with many questions, we must answer the first one.

2 Questions 2.1 Q1 For this question, every encryption scheme satisfies complete correctness. Security is for a single message. 2.1.1 A Let h1, h2 be negligible functions (that are never equal to zero). Prove or disprove: 1. is negligible as well. 2. h h2 is negligible as well.

2 Questions 2.1 Q1 For this question, every encryption scheme satisfies complete correctness. Security is for a single message. 2.1.1 A Let h1, h2 be negligible functions (that are never equal to zero). Prove or disprove: 1. is negligible as well. 2. h h2 is negligible as well.

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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