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HTTP protocol : how web browsers work

 

By typing in our browser, we can find any content, video, or other information on the internet. Our smartphones, laptops, and PDAs then transmit an electrical signal to a nearby cell tower or Wi-Fi router. In plain language we call it a "http request". The DNS server is then contacted. The IP addresses of the websites are stored on the DNS server. For example, in your browser's search box, you type "http://www.example.com." Your smartphone then generates an electrical signal containing the data you've searched for. The data is then transferred to the DNS server via your cell tower and fibre optic connections. The DNS server then looks for "http://www.example.com"'s IP address. The specific request (together with the IP address) is then forwarded to the webserver. The Webserver then sends HTML files (request files of a particular website) to the computer that generated the request. HTML, CSS, and JavaScript files are all transmitted to the desired smartphone or computer. The specific web page is then shown on your end through your web browser.

When we search the internet, we don't just get responses from web servers. Databases or Data Servers display data the majority of the time. For instance, suppose you're looking for your semester's results on your college's website. Then you enter your name, roll number, password, and other personal information. And you can see the result. Where all of the students' results are stored in a database. Others will be unable to see your results on your college's website unless they have the right credentials, password, and so on. The Web Server only shows HTML, CSS, and JavaScript files that create divisions, menus, dropdown menus, slideshows, different colors, texts, and different forms (where you enter information such as username and password), among other things.

Similarly, any website or portal that collects your information stores it in its databases. If you try to access your account later, it will display the data kept in their databases. On practically every online platform, such as food ordering sites, shopping sites, and so on, similar things happen.

We can conclude that databases or data servers can only show data to the intended users if valid credentials are entered. Web Server, on the other hand, just sends the HTML files and your browser displays the HTML files that forms the front end of your webpage (templates, etc.), whereas servers handle all backend operations, processing, and so on. After all, we can manipulate data in the backend (in databases or data servers).  

The answer will be lengthy if you inquire about the entire procedure in the context of computer networking. To read more, go to the link below.


Summary & References

  • All websites' IP addresses are stored on the DNS server.
  • The files (HTML, CSS, and JavaScript files) of a website or webpage are stored on a webserver.
  • Read more about Telecommunication Computer Network


[1] Mechanism of Wireless Communication

[2] Routing and Switching.



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  Interests: Signal Processing, Telecommunication, 5G Technology, Present & Future Wireless Technologies, Digital Signal Processing, Computer Networks, Millimeter Wave Band Channel, Web Development
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