Let F: F(2)4→ F(2)³ be a 4×3 S-box function of a block cipher such that F(x1,X2,X3.X4 )= (Y1,92-Y3), where y1 = X1X2X3 © X3X4 © x1 © X2, Y2 = X1X2X3 © X3X4 © X2 and y3 = x1 e x2 © X4 © 1. We consider single round of the block cipher with key k = (kq, k2, k3, ka ) is xored bitwise to the plaintext bits before obtaining the output by applying F. Which following relations is valid? O k1 = x1 y1 Oy2 and k2 e k4 =1 0 x2 y1 Ð y2 ®y3 O k1 = x1 O y2 and k2 O k4 = 1 0 x2 O x4 Ð y1 O y2 Ð y3 O k1 = x1 y1 Oy2 and k2 ☺ k4 =1 0 x2 Ð X4 Ð y1 y2 ®y3 O k1 = x1 y1 y2 and k2 ® k4 = 1 O x2 © x3 ® y1 Ð y2 Ð y3

Let F: F(2)4→ F(2)³ be a 4×3 S-box function of a block cipher such that F(x1,X2,X3.X4 )= (Y1,92-Y3), where y1 = X1X2X3 © X3X4 © x1 © X2, Y2 = X1X2X3 © X3X4 © X2 and y3 = x1 e x2 © X4 © 1. We consider single round of the block cipher with key k = (kq, k2, k3, ka ) is xored bitwise to the plaintext bits before obtaining the output by applying F. Which following relations is valid? O k1 = x1 y1 Oy2 and k2 e k4 =1 0 x2 y1 Ð y2 ®y3 O k1 = x1 O y2 and k2 O k4 = 1 0 x2 O x4 Ð y1 O y2 Ð y3 O k1 = x1 y1 Oy2 and k2 ☺ k4 =1 0 x2 Ð X4 Ð y1 y2 ®y3 O k1 = x1 y1 y2 and k2 ® k4 = 1 O x2 © x3 ® y1 Ð y2 Ð y3

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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