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Computer Network

-1

Suppose you visit a website using the browser. The IP address for the associated URL is not cached in your local host, so a DNS lookup is necessary to obtain the IP address. Suppose that your local DNS server is ip-srv1.vanderbilt.edu and the round-trip time (RTT) from your local DNS server is denoted as RTT_dns_local. The local DNS server performs iterative queries to a Root DNS server, a TLD DNS server and an Authorative DNS server. The round-trip time from the local DNS server to these DNS servers are denotd as RTT_dns_root, RTT_dns_tld, and RTT_dns_auth, respectively. Suppose that the round-trip time from your local host to this website is RTT_web. Further suppose that the web pass you visit is short, so that its transmission time of the page can be omitted. The web page references 8 small image objects hosted on the web site. Lets assume zero transmission time for the image objects as well. how much time elapse from when you click on the link until the web page is fully displayed (with all image objects) on your browser?

Consider the following scenarios and provide your solutions respectively.

  • The browsing is using persistent HTTP. Please help me about this question.
This question is marked "community wiki".

asked 12 May '12, 00:42

sanjit's gravatar image

sanjit
1222
accept rate: 0%

1

Another Homework assignment?!

(12 May '12, 04:18) Landi

The wording says it all...

(12 May '12, 05:41) Jasper ♦♦

One Answer:

1

The question cannot be answered as this is unknown:

  • does the browser load the images in parallel or sequentially
  • how much CPU cycles does it take to render the images in the browser
  • how much CPU cycles are available for the browser, meaning how high is the load on the PC
  • how long is one CPU cycle

BTW: don't you think your teacher/professor will also read this forum and detect your attempt to cheat? ;-))

EDIT: As the question is all about DNS, I recommend reading/watching this:

http://www.howstuffworks.com/dns.htm
http://www.youtube.com/watch?v=XKoomsRMyCU

Regards
Kurt

answered 12 May '12, 01:00

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
24.8k1039237
accept rate: 15%

edited 12 May '12, 02:12