Important Questions

1. What happens when you enter google.com in the web browser?

• Below are the steps that are being followed:

• Check the browser cache first if the content is fresh and present in cache display the same.

• If not, the browser checks if the IP of the URL is present in the cache (browser and OS) if not then request the OS to do a DNS lookup using UDP to get the corresponding IP address of the URL from the DNS server to establish a new TCP connection.
• A new TCP connection is set between the browser and the server using three-way handshaking.
• An HTTP request is sent to the server using the TCP connection.
• The web servers running on the Servers handle the incoming HTTP request and send the HTTP response.
• The browser process the HTTP response sent by the server and may close the TCP connection or reuse the same for future requests.
• If the response data is cacheable then browsers cache the same.
• Browser decodes the response and renders the content.