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Privacy and Security Exam Feb 9th, 2016 First name: ________________________ Last name: ________________________ Matricola: ________________________ Signature: ________________________ Challenges? [ ] (Y) [ ] (N) Instructions ● The exam is composed of 7 pages. ● Just as a cross check, tell us whether you have completed the homeworks, by putting an "X" mark appropriately. ● The exam is "closed books". Please put away in a non­suspicious place (i.e. not below the desk) any note, book, or similar. You will be expelled if, at any time, if you do not follow this rule. ● You are not allowed to communicate with other students, and you will be expelled from the exam if you do. ● Shut down and store electronic devices. They will be subject to inspection if found and you may be expelled if you are found using one. ● Please answer within the allowed space. Schemes are good, short answers are recommended. ● You can write in pen or pencil, any color, but ​avoid writing in red​. ● No extra paper is allowed. ● The answers ​must be written exclusively in the space provided​ below the questions. READ CAREFULLY ​ALL THE POINTS​ OF EACH QUESTION ​BEFORE​ WRITING YOUR ​ANSWER PROPOSED SOLUTION 1 of 7 Question 1 (6 points) Consider amplification­based DoS attacks. 1. (2 points) Explain briefly how they work in general, focusing on what an attacker needs in order to implement them. The attacker sends a packet with a spoofed origin (victim address) to a machine that produces a response packet which size is orders of magnitude larger than the request packet. The attacker needs a protocol that (1) allows easy address spoofing and that (2) has an asymmetric request­response packet size, and (3) a large pool of publicly reachable machines that openly respond to those requests. 2. (2 points)…