Suppose Bob joins a BitTorrent torrent, but he does not want to upload any data to any other peers (so called free-riding). a. Bob claims that he can receive a complete copy of the file that is shared by the swarm. Is Bob's claim possible? Why or why not? b. Bob further claims that he can further make his "free-riding" more efficient by using a collection of multiple computers (with distinct IP addresses) in the computer lab in his department. How can he do that?

Suppose Bob joins a BitTorrent torrent, but he does not want to upload any data to any other peers (so called free-riding). a. Bob claims that he can receive a complete copy of the file that is shared by the swarm. Is Bob's claim possible? Why or why not? b. Bob further claims that he can further make his "free-riding" more efficient by using a collection of multiple computers (with distinct IP addresses) in the computer lab in his department. How can he do that?

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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Bob sent Alice an encrypted message. The message consists of 3 words. In each word, Bob encoded the letters as follows: A = 01, B = 02, C = 03, ..., Z = 26. The he wrote the codes next to each other to form a number that represent the word. For example, the word "WE" is encoded as: 2305 since it consists of 2 letters W=23 and E=05. After encoding, Bob encrypted each encoded word with RSA using Alice public key(pq, e) where p=100000007, q=10000019, e=13. Alice received the following 3 encrypted words from Bob: 451095483713115 570203572152011 958266071840609 She used here RSA private key (d) to decrypt the message. The first word of the message that Bob sent was: WE. Q1. What is the private key d? (enter you answer as an exact number) Q2. What is the second word of the message that Bob sent to Alice? (enter you answer as one word) Q3. What is the third word of the message that Bob sent to Alice? (enter you answer as one word) MATH
Bob sent Alice an encrypted message. The message consists of 3 words. In each word, Bob encoded the letters as follows: A = 01, B = 02, C = 03, ..., Z = 26. The he wrote the codes next to each other to form a number that represent the word. For example, the word "WE" is encoded as: 2305 since it consists of 2 letters W=23 and E=05. After encoding, Bob encrypted each encoded word with RSA using Alice public key(pq, e) where p=100000007, q=10000019, e=13. Alice received the following 3 encrypted words from Bob: 451095483713115 570203572152011 762324289903198 She used here RSA private key (d) to decrypt the message. The first word of the message that Bob sent was: WE.
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Bob sent Alice an encrypted message. The message consists of 3 words. In each word, Bob encoded the letters as follows: A = 01, B = 02, C = 03, ., Z = 26. The he wrote the codes next to each other to form a number that represent the word. For example, the word "WE" is encoded as: 2305 since it consists of 2 letters W=23 and E=05. After encoding, Bob encrypted each encoded word with RSA using Alice public key(pq, e) where p=100000007, q=10000019, e=13. Alice received the following 3 encrypted words from Bob: 451095483713115 570203572152011 958266071840609 She used here RSA private key (d) to decrypt the message. The first word of the message that Bob sent was: WE. Q1. What is the private key d? (enter you answer as an éxact number) ord) Q2. What is the second word of the message that Bob sent to Alice? (enter you answer as one Q3. What is the third word of the message that Bob sent to Alice? (enter you answer as one word)
Secret Sharing Is The Important Topic Of Cryptography. Suppose We Have M People. We Want Any 1+1 Of Them To Be Able To launch a missile attack
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