What happens when you type google.com in your browser and press Enter

I believe you have ever wondered what happens behind the scenes when you type a URL like ‘ https://www.google.com’ into your browser and press Enter? It’s an interesting journey that involves multiple components working together in order to deliver the web page you requested. In this blog post, we’ll explore the complex process step by step, from the moment you initiate the request to the moment you see the webpage rendered on your screen.

DNS Request

The journey begins with a Domain Name System (DNS) request. When you type “https://www.google.com" into your browser and press enter, your computer needs to find the corresponding IP address of the Google server to establish a connection. It sends a DNS query to a DNS server, which then translates the human-readable domain name (www.google.com) into a machine-readable IP address (e.g., 172.217.7.196).

TCP/IP

Once the IP address is obtained, the browser initiates a Transmission Control Protocol (TCP) connection to the server using the Internet Protocol (IP). TCP/IP is the set of protocols responsible for establishing and maintaining communication between devices on the internet. TCP ensures data integrity by dividing it into packets and ensuring they reach their destination, while IP handles routing across the internet. Finally, the server establish a reliable connection for data exchange.

Firewall

As the data packets travel across the internet, they may encounter firewalls, which act as barriers between trusted internal networks and untrusted external networks. Firewalls inspect incoming and outgoing traffic based on predefined security rules to prevent unauthorized access and protect against malicious activities.

HTTPS/SSL

In the modern web, security is important. To ensure the confidentiality and integrity of data transmitted over the network, Hypertext Transfer Protocol Secure (HTTPS) is used. HTTPS encrypts the data exchanged between the browser and the server using Secure Socket Layer (SSL) or Transport Layer Security (TLS) protocols. This encryption acts like a secure tunnel and ensures that no hacker or spyware attacker cannot intercept sensitive information like passwords or credit card details.

Load-Balancer

Large-scale websites like Google usually employ load balancers to distribute incoming traffic across multiple servers. Load balancers optimize resource utilization, improve responsiveness, and enhance reliability by evenly distributing requests among available server resources. This ensures that no single server becomes overwhelmed with requests, leading to faster and more reliable service delivery. Load balancing ensures that no single server gets overwhelmed, thus maintaining optimal performance.

Web Server

Once the request reaches the appropriate server, typically a web server like Apache or Nginx, the server processes the request and retrieves the requested web page or resource. The web server dynamically generates the HTML content based on the request parameters and any server-side logic associated with the requested URL.

Application Server

In some cases, especially for dynamic web applications, the web server may communicate with an application server to process a bit more complex requests. The application server executes the server-side code, interacts with databases, and performs any necessary computations to generate the final content to be sent back to the client.

Database

Behind most web applications lies a database where the application server retrieves and stores data. Whether it’s user information, search results, or product listings, databases play an important role in providing dynamic and personalized content to users. The application server queries the database to fetch relevant data, which is then processed and included in the web page sent back to the client.

Conclusion

From the initial DNS lookup to the final database query, the journey of a web request involves a complex interplay of network protocols, security measures, server infrastructure, and data processing. Understanding this process provides insight into the inner workings of the internet and the technologies that power the modern web. Next time you type a URL into your browser, take a moment to appreciate the complex dance of data that takes place behind the scenes to bring you the web content you requested.