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Embedded image serial or parallel?

0

here is a test site i'm using to learn wireshark: bitly.com/qPLPXp

I was asked whether my web browser downloads the images download in serial, or in parallel?

first image is hosted by that website itself & the second image is on another server.

how can I tell if they were downloaded in serial or parallel?

Thank you

asked 31 Oct '12, 15:47

smc20's gravatar image

smc20
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3 Answers:

1

As Jasper would say "Nice, another homework assignment". Rather than just give you the answer, I'll give you some things to think about that should lead you to the answer.

  • Do you know what protocol is used to download the images?
  • Do you know what "commands" the protocol uses to download a specific image?
  • Do you know how to determine the command has completed?
  • Can you see those commands in your Wireshark capture of the browser downloading the page?
  • Are those commands issued sequentially, i.e. is the 2nd command only sent after the first one has completed?

answered 01 Nov '12, 01:04

grahamb's gravatar image

grahamb ♦
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what kind of answer is that? Answering a question with more questions?... better do not reply

(02 Jan '14, 13:30) quitoart

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I was asked whether my web browser downloads the images download in serial, or in parallel?

One answer to the question.

what did you try to figure out what happened at the network level.

Regards
Kurt

answered 01 Nov '12, 02:58

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
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edited 01 Nov '12, 14:49

0
  1. Can you tell whether your browser downl oaded the two images serially, or whether they were downloaded from th e two web sites in parallel? Explain. Answer: By checking the TCP ports we can see if our files were dow nloaded serially or in parallel. In this case the 2 images were transmitted over 2 TCP connections therefore they were downloaded serially.

link http://inst.eecs.berkeley.edu/~ee122/sp06/Homeworks/Ethereal_HTTP_Solution.pdf

answered 02 Jan '14, 13:49

quitoart's gravatar image

quitoart
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accept rate: 0%

In the specific case illustrated there may be some form of parallelism as frame 179 has an http continuation from 165.193.123.218 which may be part of the first image request and as this occurs after the start of the retrieval of the 2nd image looks like a parallel request.

(02 Jan '14, 14:39) grahamb ♦

fair enough..

(02 Jan '14, 14:58) quitoart