web stack (1)

What Happens When You Type https://www.google.com in Your Browser?
Have you ever stopped to think about what happens behind the scenes when you type a URL into your browser and press Enter? While it may seem like magic, there is actually a series of events that occurs to allow you to interact with the website.

In this post, we'll take a closer look at what happens when you type https://www.google.com into your browser and press Enter. We'll cover the following topics:

DNS request
TCP/IP connection
Firewall
HTTPS/SSL
Load-balancer
Web server
Application server
Database
1. DNS Request
The first step in this process is the DNS (Domain Name System) request. When you type in a URL like https://www.google.com, your computer needs to know the IP address of the server where the website is hosted. It does this by making a DNS request to a DNS server.

DNS lookup

The DNS server looks up the IP address associated with the domain name and sends it back to your computer. This process is called a DNS lookup.

2. TCP/IP Connection
Next, your computer establishes a TCP (Transmission Control Protocol) connection with the server. TCP is a set of rules that govern how data is transferred over the internet. It ensures that data is transferred reliably and in the correct order.

3. Firewall
If the server has a firewall set up, the connection request will need to be approved by the firewall before it can be established. The firewall checks the request against a set of rules to determine whether it should be allowed through or blocked. This helps to secure the server and prevent malicious traffic from reaching it.

4. HTTPS/SSL
Once the connection is established, the browser sends an HTTPS (Hypertext Transfer Protocol Secure) request to the server. HTTPS is a secure version of the HTTP protocol that is used to transfer data on the web. It encrypts the data being transferred to prevent it from being intercepted by third parties.

HTTPS

5. Load-balancer
If the server has a load-balancer set up, the HTTPS request will be routed through it. A load-balancer is a device that distributes incoming requests across a group of servers to balance the load and ensure that the system remains stable and efficient. This is especially important for websites that receive a large volume of traffic.

Load-balancer

6. Web server
The request is then forwarded to the web server, which processes the request and sends back the appropriate response. The web server retrieves the requested webpage and any associated resources (such as images, videos, or other files) and sends them back to the browser.

7. Application server
If the webpage requires dynamic content (content that is generated in real-time), the request may be forwarded to an application server. The application server processes the request and generates the dynamic content, which is then sent back to the web server to be included in the final webpage.

8. Database
If the webpage requires access to data stored in a database, the application server may need to request this data from the database server. The database server retrieves the requested data and sends it back to the application server, which includes it in the final webpage.

Finally, the fully-assembled webpage is sent back to the browser, which renders it for the user to interact with. And that's what happens when you type https://www.google.com into your browser and press Enter!

I hope this post has helped you understand the various steps that occur when you access a website. While there are many technical details involved in this process, it's amazing to think that all of this happens in just a matter of seconds.

If you'd like to learn more about how the web works, check out these resources:

[How the Web Works from Mozilla] Developer Network
[How Does the Internet Work?] from HowStuffWorks
[How Web Servers Work] from HowStuffWorks
Thanks for reading!