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Basic Question about Users in a System (like the PF for example)

  1. May 1, 2017 #1


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    Hi just curious,
    What is the computing/networking model for a site with many users, say, as PF? Is it to grant access to each user to a shared drive? Sorry if this is too simple. I mean, I understand that first I login and I have to be first authenticated, then authorized to access certain network resources. How is that all stored and organized. Is it a domain controller where I am part of a collection of users and/or groups with specified permissions? EDIT: In a database system such as SQL Server I understand I first get access to the general network with a login, either through Windows or through SQL Server. In order to use a database, I must be made into a user of said database. But tha t just gives me access to the database, without the ability to do anything. I must then be assigned a role, which brings with it a set of permissions. How does this work when granting access to different users to a general site/network?
    Last edited: May 1, 2017
  2. jcsd
  3. May 1, 2017 #2
    Everything is stored in a database and SQL in one form or another is very popular.
    The physical storage media can vary but very often the site operator simply rents server resources from a large provider, (these are known as web farms).
    The web farm takes care of the physical resource management and maintenance, the site operator does not need to be involved in that.
    Usually these web farms offer a complete package along with the physical resources, this would include all the necessary server software, for example a web server (Often it's Apache web server running under some version of Linux.)
    The site operator uploads web pages and other material to their allocated space usually via FTP.
    Depending on the package they can also upload their own unique 'server side' software, many languages are available, PHP is probably most widely used.
    Site administrators have a 'control panel', which they use to assign permissions for different levels of normal users.
  4. May 1, 2017 #3


    Staff: Mentor

    Basically you are interacting with a web application server. You send it a URL and it sends back a web page. You enter some text in the web page and press the submit. Your browser sends a form to the server. The server parses the form stores the text in it database and returns a web page back to you with the updated information.

    If you click a link to some media file then the web server streams it back to you and your browser knows how to display it on your screen.

    Everything is very controlled. On the most open of web sites you can browse limited portions of the file system but it is controlled by the web server who processes your URL request.

    In some ways this model of interaction is a lot like a command line session. You type a command and the shell runs the command and returns some text to you. Sometimes you'll get text and sometimes you'll get errors. To the user, the shell controls access to the files based on the user's access rights i.e. What groups they are a member of and the files permissions based on the file owner and group its in.
    Last edited: May 1, 2017
  5. May 2, 2017 #4
    Websites aren't shared folders or drives, they are a series of "get" requests for information and they are downloaded files from a file server and in the old days it was as unsecured as FTP (a protocol that simply allowed you to download files in plain text).

    Now it ought to be a little bit more secured than that. But that's the gist of it.

    As others have mentioned, when you login you are cross-referencing two objects with a database of objects, you download a landing page file that is the login webpage which contains script that when you press enter sends the information back, if there's an SSL connection it's somewhat encrypted.

    If that information is correct then you are given access to other downloadable content of the website based on your account. Since everything is a downloadable or uploadable content, (such as I upload data to the webserver when writing this post) if your account has those permissions the webserver will allow it.

    That's it in a nutshell.

    Databases for Websites are not usually SQL, correct? Most webservers are Apache and not IIS based?
  6. May 2, 2017 #5


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    There's no single model for a website. The WWW is a set of standards that essentially allow a universal client (the web browser) to communicate with a standard web server. Without this, every website might need its own client.

    But, behind the front-end webserver there could be anything from a single PC to an IBM mainframe.

    There are as many possible data access models as you can imagine. You may have access as a specific user (change your profile) or as part of a user group (moderators).

    In many business applications you have a whole superstructure of access rules maintained by system administrators. More general things may be in something like Active Directory, but a lot of rules can be held in specific application software.
  7. May 2, 2017 #6


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    There are many flavors of SQL and many web sites use one of them. Apache servers are frequently paired with MySQL for instance.

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