Talk:Web Science/Part1: Foundations of the web/Hypertext Transfer Protocol/A simple web client

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Join the discussion: Ask and questions and provide answers[edit | edit source]

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Notes on the video[edit source]

I wanted to mention that you should please use an external keyboard or mic. But your typing does not seem to be in sync with the deep, loud and constant background noises. Whatever it was, its sound is prevalent thanks to my subwoofer. --Onse (discusscontribs) 09:13, 12 November 2013 (UTC)[reply]

Check your understanding clarification[edit source]

Q2: In the video I say You could get an UnknownHostException because someone might not know our server studywebscience.org. What do I actually mean with this statement?

a) Why the following is true?

  • The host name studywebscience.org could not be entered in my local host file.

We always will ask DNS external servers, if there is no such host in your /etc/hosts .

b) Should be true:

  • the computer might not be connected to the internet.

Q3: When will an IOException be thrown in the program?

You marked as true:

  • If the internet is censored and the packages to the host are blocked.

I think it depends on how the host is blocked. I see several options. Firstly, the host can be redirected to the special ip address, where it will be a statement that the site is closed (no error actually). Secondly, it can be blocked by ip, but I can not find information on how it works. Hence, I do not mind how Java will react, maybe it will cause "NoRouteToHostException"? --oleamm (discusscontribs) 19:41, 25 November 2013 (UTC)[reply]

Answer Q2 : If we get UnknownHostException that means the IPAddress of the host "studywebscience.org" can not be resolved. --Koblenz (discusscontribs) 12:02, 14 November 2014 (UTC)[reply]
That means the NameServer (to which we are going to make our DNS query) could not able to resolve the IP for this DNS request. --Koblenz (discusscontribs) 12:04, 14 November 2014 (UTC)[reply]