Consider a simple system with 8-bit block size. Assume the encryption (and decryption) to be a simple XOR of the key with the input. In other words, to encrypt x with k we simply perform x⊕k giving y. Similarly, to decrypt y, we perform y⊕k giving x. You are given the following 16-bit input “F5C6” in hexadecimal. You are provided IV as “8C” in hexadecimal. The key to be used (where appropriate) is “49” in hexadecimal. Compute the encrypted output with the following methods. Express your final answer, for each of them, as 4 hexadecimal characters so it is easy to read. A. Using ECB B. Using CBC C. Using OFB D. Using CFB

Consider a simple system with 8-bit block size. Assume the encryption (and decryption) to be a simple XOR of the key with the input. In other words, to encrypt x with k we simply perform x⊕k giving y. Similarly, to decrypt y, we perform y⊕k giving x. You are given the following 16-bit input “F5C6” in hexadecimal. You are provided IV as “8C” in hexadecimal. The key to be used (where appropriate) is “49” in hexadecimal. Compute the encrypted output with the following methods. Express your final answer, for each of them, as 4 hexadecimal characters so it is easy to read. A. Using ECB B. Using CBC C. Using OFB D. Using CFB

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter8: Data And Network Communication Technology

Section: Chapter Questions

Problem 41VE

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