The Entire Process Of Handling URL Requests.
Published: 2023-09-17 23:17:22

**Case-Study**: Looking at the "https://www.google.com" URL.

**Introduction**

In the modern digital age, the World Wide Web has become an integral part of our lives. Every time you open your browser, type in a URL, and press Enter, a complex process unfolds behind the scenes. This article will guide you through the journey of a web request, explaining each step in detail, from the moment you type "https://www.google.com" into your browser to the moment you see the Google homepage.

1. _DNS Request_ (Domain Name System)

The journey begins with the Domain Name System (DNS). When you enter a URL like "www.google.com," your computer doesn't know where to find Google's servers. It sends a DNS request to a DNS server, which acts like an internet phonebook. The DNS server translates the human-readable domain name ("www.google.com") into an IP address, such as "216.58.214.36." This IP address is essential for your computer to locate the target server on the internet.

2. _TCP/IP_ (Transmission Control Protocol/Internet Protocol)

With the IP address in hand, your computer initiates a connection using the Transmission Control Protocol (TCP) and Internet Protocol (IP). TCP ensures that data is transmitted reliably, breaking it into small packets and verifying their successful delivery. IP, on the other hand, routes these packets across the internet to the destination server, Google's in this case.

3. _Firewall_

Firewalls act as gatekeepers for your computer. They filter incoming and outgoing traffic, blocking any potentially harmful or unauthorized data packets. Firewalls help ensure your computer's security by allowing only trusted connections to pass through.

4. _HTTPS/SSL_ (Hypertext Transfer Protocol Secure/Secure Sockets Layer)

Security is paramount when transmitting sensitive information over the internet. To establish a secure connection, your browser and the web server engage in a process called the SSL handshake. During this handshake, they exchange cryptographic keys to encrypt and decrypt data. The resulting secure connection is identified by "https://" in the URL and the padlock icon in your browser's address bar.

5. _Load-Balancer_

Large websites like Google handle enormous traffic daily. To distribute this load efficiently, they use load balancers. A load balancer acts as an intermediary between your request and the web servers. It evaluates the servers' current load and directs your request to the server that can best handle it. This ensures a smooth and responsive user experience, even during peak traffic times.

6. _Web Server_

Once your request reaches the web server, it begins processing. Web servers like Apache, Nginx, or Microsoft IIS are responsible for handling incoming requests, processing dynamic content, and generating the HTML that your browser will render. In Google's case, their web servers process billions of search queries every day.

7. _Application Server_

For dynamic web applications, there's often a middle layer known as the application server. It handles tasks like database queries, business logic, and user authentication. In Google's context, this layer plays a crucial role in delivering personalized search results, managing user accounts, and handling various backend processes.

8. _Database_

Behind every web application is a database that stores, retrieves, and manages data. In Google's case, this includes storing indexed web pages, user preferences, and search history. Databases like MySQL, PostgreSQL, or NoSQL databases are used to efficiently handle vast amounts of data.

**Conclusion**

The seemingly simple act of typing "https://www.google.com" into your browser and pressing Enter sets off a chain of complex processes that involve DNS requests, TCP/IP, firewalls, HTTPS/SSL, load-balancers, web servers, application servers, and databases. This intricate web of technologies and protocols ensures that you can access information swiftly and securely on the internet.

Understanding this journey is not only crucial for software engineers but for anyone who wants to appreciate the complexity and reliability of the web. It highlights the importance of each component in delivering a seamless browsing experience, and it showcases the innovations that make the internet an indispensable part of our daily lives.

In today's tech-centric world, grasping the inner workings of web requests can open doors to exciting career opportunities. By mastering these concepts, you're not only ahead of the curve but also better equipped to navigate the intricacies of the digital landscape. So, the next time you enter a URL and press Enter, remember the fascinating journey your request embarks on, making the web a global phenomenon that connects us all.