What happens when you type google.com in your browser and press Enter
Evolution and growth is the hallmark of our world and society; a movement from where we were to where we are, and where we want to be. There is a constant change and development, exhibited by the obvious digital era we are currently in where we employ the internet for our most basic tasks, including but not limited to studying, researching, or even just finding the latest movie or song.
Following this, we can witness that, what causes innovation in the digital world we live in is the inquisitive nature of human beings, and even as children, we often tried to open up toy cars to see what made them move, or the television set to try to figure out how people climbed into it. This inquisitive nature sticks with us as adults and extends itself as we find ourselves questioning various things about our world.
This then translates to the question of what actually happens when we search for something on google, and how we are able to find such things on the internet by just clicking a button. A simple iteration of the URL https://google.com, a written phrase or word, and a click of the “Enter” button is enough to return pages of information, relevant to whatever it is that is being sought. Thus, in this blog post, I seek to adequately explain what exactly happens in that process from a technical point of view.
In order to do this, this post would begin by explaining a few concepts before proceeding to how the process actually works.
- WEB PAGES
In essence, a webpage is a text file formatted in a specific way so that your browser (such as Google Chrome, Firefox, Safari, etc.) can interpret it. This style is known as Hyper Text Markup Language (HTML). Web pages are retained on computers that offer the storage service until someone wants them and can request access to them. Servers are the name for these machines. The reason for this is that they make their content available to anyone who needs it.
2. WEB SERVERS
There are other kinds of servers, but the one we’ll be discussing in this post is the most widespread: the web server, which is the server that delivers web pages. Additionally, there are application servers, which store the application base code that is used to communicate with a web browser or other apps. The other servers are database servers; they keep a database that is accessible for updating and consulting as required.
Similar to traditional delivery services, these servers must have an address so that the person who needs their material can send a “mail” asking delivery; in turn, the person requesting the content must have an address where the server can deliver.
IP (Internet Protocol) Addresses are how these addresses are referred to; these are a combination of 4 digits with a range of 0 to 255 (one byte), separated by periods (i.e. 136.0.0.1).
The primary responsibility of a web server is to accept and process client requests for static content from a website (HTML pages, files, images, video, and so on). The client is usually always a browser or mobile application, and both the request and the web server’s answer are made via the Hypertext Transfer Protocol (HTTP) protocol. For instance; nginx is a web server.
Following the explanation of these concepts, this blog would then describe in detailed steps what occurs when we type “google.com” and hit Enter.
- DNS RESOLUTION
Like google.com, every domain name has a corresponding IP address. Because it is simpler for people to recall a string of names than a string of numbers, DNS is a crucial component of how we browse on a daily basis. Each web server has a unique IP address in text form; translating it to an IP address is a system called DNS resolution as well as DNS lookup; in this DNS stands for Domain Name Service. The content of each and every domain name we browse for is always hosted on a remote server somewhere.
The application that wants to translate, called a web crawler component, contacts a DNS server during DNS resolution, and the DNS server returns the interpreted IP address.
The web browsers first examine the operating system’s cache to see if the required domain’s IP address is available when we press enter after typing the domain name we’re looking for. However, in the absence of an IP address, a few things occur; the web browser queries the Resolving Name Server (RNS) for the IP, and if this is not known it proceeds to the ROOT. If the ROOT also does not know, it gives the location of the Top Level Domain Name to the RNS, which then stores in its cache and requests for the required IP. If this still doesn’t work, the Domain Name Registrars are used by the TLD to identify which Authoritative Name Server (ANS) the RNS needs to query, in order to find the IP required.
This then gives the web browser an address, but it still needs to get to this particular address.
2. TCP/IP
A network conversation that allows application programs to exchange data is defined by the TCP (Transmission Control Protocol) standard. The Internet Protocol (IP), which specifies how computers send data packets to one another, works with TCP. The fundamental principles governing the Internet are TCP and IP together.
Because TCP ensures that all necessary content is transmitted, it is frequently used to deliver static websites like Wikipedia or Google, email services, and to download files to your computer. This is achieved by sending the file in small data packets, each of which includes a delivery confirmation. As a result, if you are ever downloading something and your internet connection suddenly drops, you won’t have to restart because the server will already be aware of how many packets you have and how many you still need to receive. TCP has the disadvantage of being slower because it must confirm whether or not you received the previous packet before sending the next.
Thus, when the Operating system obtains the IP Address and passes it to the browser, it performs a GET HTTP Method to that IP Address. Once the request is made, the browser will send it to the OS, which then packages it in the TCP traffic protocol we previously discussed and submits it to the IP address. It is checked for security violations along the way by both the operating system’s and the server’s firewalls. Upon receiving the request, the server, which is typically a load balancer that routes traffic to all available servers for that website, responds with the IP address of the chosen server as well as the SSL, Secure Sockets Layer certificate to begin a secure session of the HTTP called, Hyper Text Transfer Protocol Secure (HTTPS).
Finally, the selected server responds with the HTML, CSS, and JavaScript files to the Operating system, which further moves them onto the browser to decipher. It is at this juncture that you obtain the website that you are familiar with.
CONCLUSION
In essence, the simple “search” and entering require a ton of complex processes behind the scenes which eventually results in the end process of what is displayed on our digital devices.
This article was written to give a general overview of how those processes work, and what it entails in general.
Thank you.
SOURCES
2. https://www.howtogeek.com/howto/27350/beginner-geek-how-to-edit-your-hosts-file/
4. https://en.wikipedia.org/wiki/Server_(computing)#Hardware_requirement
