Requirement is available in the attached document
Network Architecture I (CSEE 5110)
Assigned: Sep. 20, 2021 Due: Oct. 3, 2021
· The goal of this assignment is to assess your understanding of the material learned so far. You will need to upload your answers to canvas through the provided link of the Assignment #1.
Answers to the questions should be directly reported in this word file (inside the dedicated box). Answers should not be handwritten. You will need to upload to canvas a doc file an no images/pictures allowed in the files. No compliance to these rules will lead to zero.
This assignment will be counted for 10% of your total grade.
1) DNS – Basics
Imagine that you are trying to visit www.enterprise.com, but you don’t remember the IP address the web-server is running on.
Assume the following records are on the TLD DNS server:
· (www.enterprise.com, dns.enterprise.com, NS)
· (dns.enterprise.com, 184.108.40.206, A)
Assume the following records are on the entreprise.com DNS Server:
· (www.enterprise.com, west3.enterprise.com, CNAME)
· (west3.enterprise.com, 220.127.116.11, A)
· (www.enterprise.com, mail.enterprise.com, MX)
· (mail.enterprise.com, 247.29.126.93, A)
Q1: What transport protocol(s) does DNS use: TCP, UDP, or Both?
Q2: What well-known port does DNS use?
Q3: How many types of Resource Records (RR) are there?
Q4: Can you send multiple DNS questions and get multiple RR answers in one message? Answer with Yes or No
Q5: To which DNS server does a host send their requests to? Answer with the full name
Q6: Which type of DNS server holds a company’s DNS records? Answer with the full name
Q7: In the example given in the problem, what is the address of the DNS server for enterprise.com?
Q8: When you make the request for www.enterprise.com, your local DNS requests the IP on your behalf. When it contacts the TLD server, how many answers (RR) are returned?
Q9: In the previous question, there were two responses, one was a NS record and the other an A record. What was the content of the A record? Answer with the format: “name, value”
Q10: Assume that the enterprise.com website is actually hosted on west3.enterprise.com, what type of record is needed for this?
Q11: Now imagine we are trying to send an email to [email protected], and their mail server has the address mail.enterprise.com. What type of record will we receive?
Q12: In that MX record, what are the contents? Answer with the format: “name, value”
Q13: Does your local DNS server take advantage of caching similar to web requests? Answer with Yes or No
|Answers:Q1.Q2. Q3. Q4. Q5. Q6. Q7. Q8. Q9. Q10. Q11. Q12. Q13.|
2) Comparison of client-server and peer to peer file distribution delays
In this problem, you’ll compare the time needed to distribute a file that is initially located at a server to clients via either client-server download or peer-to-peer download.
The problem is to distribute a file of size F = 5 Gbits to each of these 8 peers. Suppose the server has an upload rate of u = 85 Mbps. The 8 peers have upload rates of: u1 = 11 Mbps, u2 = 20 Mbps, u3 = 17 Mbps, u4 = 20 Mbps, u5 = 20 Mbps, u6 = 24 Mbps, u7 = 17 Mbps, and u8 = 26 Mbps The 8 peers have download rates of: d1 = 15 Mbps, d2 = 34 Mbps, d3 = 38 Mbps, d4 = 18 Mbps, d5 = 13 Mbps, d6 = 38 Mbps, d7 = 23 Mbps, and d8 = 40 Mbps
Q1: What is the minimum time needed to distribute this file from the central server to the 8 peers using the client-server model?
Q2: What is the minimum time needed to distribute the file using peer-to-peer download?