Suppose that you share a new (unused) random key of 128-bits with a recipient. You are considering whether to use the key either as a one-time pad or with the AES block cipher in ECB mode. 1. Suppose first that you have a single message to encrypt, written in English as 16 x 8-bit bytes to make 128 bits in total. For this part assume that the key is used only once for this message. Compare the security of each of the two choices. Is one better than the other and why? 2. Now suppose that you have a second message to encrypt, also written in English as 16 x 8-bit bytes. You decide to use the same encryption method with the same key as you used for the first 128-bit message. Again, compare the security of the two choices.

Suppose that you share a new (unused) random key of 128-bits with a recipient. You are considering whether to use the key either as a one-time pad or with the AES block cipher in ECB mode. 1. Suppose first that you have a single message to encrypt, written in English as 16 x 8-bit bytes to make 128 bits in total. For this part assume that the key is used only once for this message. Compare the security of each of the two choices. Is one better than the other and why? 2. Now suppose that you have a second message to encrypt, also written in English as 16 x 8-bit bytes. You decide to use the same encryption method with the same key as you used for the first 128-bit message. Again, compare the security of the two choices.

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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