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

Introduction:

When we enter a URL like "https://www.google.com" in our browser and press Enter, we initialize an interesting process that encompasses several components working together flawlessly. In this blog post, we'll dive into the journey of a web request, covering each step from the initial DNS request to the final execution of the website. Let's explain the workings of this process and gain a better understanding of how the web stack works.

DNS Request:

The first step in the journey is the Domain Name System (DNS) request. The browser sends a query to a DNS resolver, typically provided by the Internet Service Provider (ISP). The resolver then looks up the Internet Protocol (IP) address associated with the domain name "www.google.com" by querying the appropriate DNS servers. Once the resolver receives the IP address, it returns it to the browser, allowing it to establish a connection.

TCP/IP:

With the IP address in hand, the browser initiates a Transmission Control Protocol (TCP) connection to the server hosting the website. TCP ensures reliable and ordered delivery of data over the internet. The browser sends a series of packets containing the request for the web page to the server, which responds with packets containing the requested content.

Firewall:

Before the request reaches the server, it often encounters a firewall. Firewalls act as a security barrier, filtering incoming and outgoing network traffic based on predefined rules. They help protect the server by monitoring and allowing only authorized traffic, preventing potential threats and attacks.

HTTPS/SSL:

As the web request progresses, it's important to ensure the security and privacy of the transmitted data. This is where Hypertext Transfer Protocol Secure (HTTPS) and Secure Sockets Layer (SSL) come into play. When we type "https://" in the URL, we are indicating that we want a secure connection. The browser and server establish an encrypted connection using SSL certificates, which verify the authenticity of the server and encrypt the data exchanged, protecting it from eavesdropping and tampering.

Load Balancer:

To handle high traffic and distribute requests effectively, popular websites like Google employ load balancers. A load balancer acts as a traffic manager, distributing incoming requests across multiple servers. It ensures that no single server is overwhelmed and maximizes availability and performance. The load balancer examines factors like server health, capacity, and network conditions to make informed routing decisions.

Web Server:

Once the request reaches the appropriate server, it is handed off to a web server. The web server is responsible for processing the request, fetching the requested resources, such as HyperText Markup Language (HTML), Cascading Style Sheet (CSS), JavaScript, and images, and generating a response. The response is then sent back to the browser.

Application Server:

In some cases, when dynamic content is involved, the web server communicates with an application server. The application server executes the server-side code, interacts with databases, performs business logic, and generates the necessary data to complete the response. This interaction between the web server and application server enables dynamic and personalized web content.

Database:

For websites that rely on data storage and retrieval, the application server interacts with a database. The database stores and manages structured data, providing the application server with the necessary information to fulfill the user's request. This could involve querying the database, updating records, or retrieving specific information.

Conclusion:

The process of typing a URL in the browser and seeing a website load involves a complex sequence of interactions between various components. Understanding this web stack workflow, from DNS requests to database interactions, is crucial for software engineers to build scalable and performant applications. By gaining insight into each step of the journey, we can appreciate the multifaceted mechanisms that make the internet work

A schema?illustration of the flow of the request created when you type https://www.google.com in your browser and press?Enter.