1. Homepage
  2. Exam
  3. [2022] COMPSCI 711: Parallel and Distributed Computing - Final Exam - Q5 HTTP Latency

[2022] COMPSCI 711: Parallel and Distributed Computing - Final Exam - Q5 HTTP Latency

This question has been solved
Engage in a Conversation

Question 5


CourseNana.COM

This question relates to how parallel downloads affect HTTP latencies as seen by an end-user. The latencies are incurred when a web client requests information from a server www.soleletapu.com. You will be using the simplified latency model discussed in the lectures, and reproduced in the link below. CourseNana.COM

Simplified latency model CourseNana.COM

The bandwidth between the client and server (i.e., www.soleletapu.com) is deemed to be 240 Mb/s and the round trip time(RTT) is estimated to be 100ms. Note that the RTT is the time it takes for small packet to travel from client to server and then back to the client. Note also that a kilobyte(kB) is 1000 bytes, and a megabyte(MB) is 1000 kilobytes. CourseNana.COM

The client(i.e., the browser) obtains from the server a 960 kB HTML file named 8747376.html that would compress to 80 kB when compressed with gzip. The HTML file includes references to 7 PNG images. The file size of the images, given in MB, are as follows: 3, 4, 4, 2, 1, 4, 4. The images are named image 0 through to image 6 for convenience, and the image file sizes here are given in that order. The following questions refer to this collection of images and the HTML file. Where applicable, requests could be sent back-to-back without having to wait for the responses. CourseNana.COM

Please wirte down your answers to the following questions in milliseconds. Do not write the units however, For example, if your answer to a question is 34.5ms, just write down 34.5 as the answer. CourseNana.COM

  1. The client side to the server an HTTP request for the HTML file. A partial request indicating some of the key header elements is shown below. CourseNana.COM

     GET /8747376.html HTTP/1.1
     Connection: close
     Accepting-Encoding: identity
     Cache-control: no-store

    You shoule assume similar requests to be sent by the client for the images sequentially. The client needs to process the HTML file to find out the URLs of each image, and this processing can start only after the client receives the entire file. For simplicity, assume that this processing time is negligible. How long would it take the client, from the time the user clicked to access the URL corresponding to the HTML file, to get the file and the images it refers to? Assume that none of files (HTML as well the images) have previously been accessed. CourseNana.COM

  2. Now, repeat question 1 above with the following (partial) HTTP request for the HTML file. CourseNana.COM

     GET /8747376.html HTTP/1.1
     Connection: keep-alive
     Accepting-Encoding: identity
     Cache-control: no-store

    You should assume similar requests to be sent by the client for the images. CourseNana.COM

  3. Now, repeat question 1 above with the following (partial) HTTP request for the HTML file. CourseNana.COM

     GET /8747376.html HTTP/1.1
     Connection: keep-alive
     Accepting-Encoding: gzip
     Cache-control: no-store

    You should assume similar requests to be sent by the client for the images. CourseNana.COM

  4. This question is similar to question 1 above with the difference that the client is now able to send parallel requests. Recalculate the time with this in mind. assuming that the client now initiates as many parallel requests as possible, and the server is able to handle all those requests in parallel. A partial request indicating some of the key header elements is shown below: CourseNana.COM

     GET /8747376.html HTTP/1.1
     Connection: close
     Accepting-Encoding: identity
     Cache-control: no-store

    The client needs to process the HTML file to find out the URLs of each image, and this processing can start only after the client receives the entire file. For simplicity, assume that this processing time is negligible. Assume that none of the files (HTML as well the images) have previously been accessed. CourseNana.COM

  5. Now, repeat question 4 above with the following (partial) HTTP request for the HTML file: CourseNana.COM

     GET /8747376.html HTTP/1.1
     Connection: keep-alive
     Accepting-Encoding: identity
     Cache-control: no-store

    Assume that the client initiates as many parallel requests as possible, and the server is able to handle all those requests in parallel. Also assume that the request for the first of the images(i.e., image 0) is sent on the re-used TCP connection CourseNana.COM

  6. Now, repeat question 4 above with the following (partial) HTTP request for the HTML file: CourseNana.COM

     GET /8747376.html HTTP/1.1
     Connection: keep-alive
     Accepting-Encoding: gzip
     Cache-control: no-store

    Assume that the client initiates as many parallel requests as possible, and the server is able to handle all those requests in parallel. Also assume that the request for the first of the images(i.e., image 0) is sent on the re-used TCP connection CourseNana.COM

Get the Solution to This Question

WeChat WeChat
Whatsapp WhatsApp
University of Auckland代写,COMPSCI 711代写,Parallel and Distributed Computing代写,University of Auckland代编,COMPSCI 711代编,Parallel and Distributed Computing代编,University of Auckland代考,COMPSCI 711代考,Parallel and Distributed Computing代考,University of Aucklandhelp,COMPSCI 711help,Parallel and Distributed Computinghelp,University of Auckland作业代写,COMPSCI 711作业代写,Parallel and Distributed Computing作业代写,University of Auckland编程代写,COMPSCI 711编程代写,Parallel and Distributed Computing编程代写,University of Aucklandprogramming help,COMPSCI 711programming help,Parallel and Distributed Computingprogramming help,University of Aucklandassignment help,COMPSCI 711assignment help,Parallel and Distributed Computingassignment help,University of Aucklandsolution,COMPSCI 711solution,Parallel and Distributed Computingsolution,