RoadToWebDev Day#3 —Internet
This is a part of my ongoing series about exploring the Road To Web Development, you can find rest of the blogs here
How does the Internet work?
The internet is usually imagined to be working above clouds. But it’s not like that. The Internet is a network of optic fiber cables, lying under the ground. Any number of computers, directly connected to the cables, can communicate with each other. A server is a special type of computer where the web-pages are stored. To identify the required computer, every computer has its own identity known as the Internet Protocol address or (IP) address. A typical IP address looks like 208.65.153.238. It seems difficult to remember a string of numbers such as this to search a web-page such as youtube.com or else. Hence each IP address is given a name known as the Domain name.
Any data we get through the internet is stored in the servers which are located in the data center which is normally thousands of miles away. The data travels thousands of miles through the optic fibers in the form of light signals. These light signals are converted to electrical signals with the help of a router. From the server, the data is sent to you in the form of a large collection of 0s and 1s. The efficiency of the data transfer depends on the way this collection of 0s and 1s are sent. These 0s and 1s are packed into small packets and are transmitted. Each packet of the data consists of the sequence number and the IP address of the server and your computer. There are many paths available to the data packets in order to reach the desired location. So every data packet takes the best path. After the data packets reach your computer, they are rearranged in the order with the help of the sequence number.
How does DNS work?
The DNS provides a mapping between human-readable names or domain names (like www.amazon.com) and their associated IP addresses (like 205.251.242.103). It can be compared to a phone book where we find the phone number of a specific person with the help of its name. In a similar manner, DNS provides you the IP address of the respected domain names.
Here are some steps of getting the desired IP address using DNS:
- First of all, a user enters a desired domain name in the search bar and presses enter. Let us take the example of www.youtube.com.
- This request is directed to a DNS resolver. The user’s Internet Service Provider(ISP) manages the DNS resolver.
- The DNS resolver passes on the request to a DNS root name server.
- The DNS root name server identifies the last part of the domain name. Here it is .com hence according to the last part of the domain DNS root name server directs the request to the respective name server. This name server returns the IP address to the DNS resolver.
- Hence, the DNS resolver gets the required IP address and it returns the IP address to the web browser.
And in this manner, the user gets his desired webpage.
What is Web Hosting?
Web Hosting is the process of buying or renting space for the website. The amount of space allocated on a server to a website depends on the type of hosting. The types are differentiated by the kind of technology used for the server, the level of management provided, and other facilities. The users can connect to the created website with the help of the server.
How does a browser work?
The main task of a browser is to take the request from the user and display the required result.
Let’s understand the process briefly:
First of all, the user enters the request to the web browser. In order to get the desired results from the web server, the correct IP address of the respective server is required. This IP address is obtained from the local cache memory or the DNS server. After getting the required IP address, the web browser sends the HTTP request to the server. The web browser asks the server to send the required file(normally a text file formatted in HTML) to display it. The browser interprets the HTML page and interprets the remaining objects such as images, audios, videos, and others. After this process, the browser displays the required content. And finally, the browser will wait for the user to make the next request and start the whole process again. (provided the internet connectivity is good ;)
References:
