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  1. #1
    Join Date
    Dec 2011
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    4

    Why are there predefined application specific ports?

    Why are there predefined application specific ports? for example, why is HTTP associated with port 80?

  2. #2
    Join Date
    Oct 2006
    Location
    Sweden
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    3,654

    Re: Why are there predefined application specific ports?

    It's easier since you don't have to remember what port to use as well as the url. In some way it's just like that you don't have to use the long distance prefix when you dial a local phone number.
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  3. #3
    Join Date
    Oct 2005
    Location
    Minnesota, U.S.A.
    Posts
    680

    Re: Why are there predefined application specific ports?

    Quote Originally Posted by maybnxtseasn View Post
    why is HTTP associated with port 80?
    So you know which port to connect to on the remote computer. Without ports, the remote computer has no idea what to do when a connection is made. With a port, the computer sees a connection on port 80, says, "aha!", and activates the web server to handle it.

    The reason it is 80 is because of an arbitrary list that was made back in the early 70s to handle standard requests. This list is still maintained and users can register specific ports. We are up around 13000 now for specifically registered ports, I believe.

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