Web Application Built on Network Application
Network Application:
Every network application is based on the client-server model. A server manages some resource, and it provides some service for its clients by manipulating that resource.So with this model, a network application consists of:
1) a server parent process with one/many child process and
2) one or more client processes.
For example: A client can be a Web client or a FTP client. A server can be a Web server or a FTP server.
Network Application – Web Client-Server Application:
Web clients and web servers interact using application-level protocol known as HTTP.
Web Client:
1) opens an Internet connection to a server and requests web content.
2) The web client reads the web content and display it on the screen.
Web Server:
1) understand HTTP request and send HTTP response
2) read disk file or run an executable file (written in PHP/Python/Java/JavaScript)
3) responds with the requested content by writing the static content/the output of an executable file to an open file with a connected descriptor.
4) close the connection.
Web Application/Content:
Web servers provide web content to web clients in two different ways:
1) Fetch a disk file (for example, HTML, CSS or JavaScript file, image)and return its contents to the client. The disk file is known as static content and the process of returning the file to the client is known as severing static content.
2) Run an executable file (written in PHP for example) and return its output to the client. The output produced by the executable at run time is known as dynamic content, and the process of running the program and returning its output to the client is known as serving dynamic content.
URLs of Web Content:
1) URL: Every piece of content returned by a Web server is associated with some file that it manages. Each of these files has a unique name known as URL.
2) Two types of URLs:
2-1) URLs for static file
2-2) URLs for executable files, which can include program arguments after the file name. A ‘?’ character separates the filename from the arguments, and each argument is separated by an ‘&’ character.
3) User may use URL like:
3-1) enter a URL,
3-2) submitting a form,
3-3) click a anchor tag or image tag,
3-4) reads a link tag or script tag
4) Clients and servers use different parts of the URL during a transaction.
4-1) A client uses the prefix of a URL to determine what kind of server to contact, where the server is, and what port it listening on.
4-2) The server use uses the suffix to find the file on its filesystem and to determine whether the request is for static or dynamic content.
Reference –
What is a server?
https://www.paessler.com/it-explained/server