How Internet works ??

The Internet

We use internet in our day to day life, we use social networking sites, we chat, we shop online, we exchange emails, we do online banking this are some examples of what we do by using internet. We will take a small example we chat using internet, have we ever thought of how many computers we use in this process?? the answer is no. We never think of such silly things, for most of the people the answer for this will be 2 computers i.e. one which is I am using to send a message and the other one is to receive the message. But the answer is no, in between this 2 computers there are dozens of computer bridging together to form a network. So collectively, the collection of this world's linked-up computers together is known as Internet. How they actually do this?? Let's take a closer look at that later.

If I ask some people to define Internet most of them will answer by naming the applications they use over internet for e.g. Google, Flipkart, facebook, and so on. But actually this is not internet, this is World Wide Web. An Internet is the underlying telecommunication network which make use of this application possible.

We can understand internet better if we assume it to be some system, this system consist of two main components the one is Hardware. This component consist of everything from cables which are used for transmission to the computer which we use. Still there are many hardware components in between this such as Routers, Switches, Servers, mobile towers, satellite, radios, smartphones and other connecting devices. All this components together forms a network and combination of this networks is known as Internet. In these networks, some of the components may act as an end points, computers, smartphone and other connecting devices which you use to read this are known as the end points or in other terms they are known as clients. Machines that store the data that we see on web are known as the Servers. Other hardware components are the nodes, which help in connecting the route of a traffic. In between this route it comes the transmission lines, it can be the physical i.e. cables or fiber optics, or it can be wireless i.e. using satellite or radio signals using mobile towers. 

The Second component of this system is Protocols, without this the hardware component would have failed to work. Protocols are the set of rules that should be used to complete some task. without this rules communication between two devices would fail, different machine would not understand each other without this Protocols.

There are many protocols that we use over the internet, One of them is HTTP. It stands for Hyper Text Transfer Protocol which is used to view web pages in browser. Next protocol is FTP, i.e. File Transfer Protocol which is used to transfer files over internet. There are many such protocols that are used to do some specific task over the internet. Some of the important protocols are TCP stands for Transmission Control Protocol and IP i.e. Internet Protocol. Mostly we use them together i.e. TCP/IP.

We have heard of IP addresses, This addresses follows Internet Protocols. Each computer or any node which is connected to internet has this address. We presently use 32-bit address known as IPv4. But the problem we are facing is we are running out of addresses. So in future we will be using IPv6 i.e. address of 128 bits and that will be enough for the large demand.

When we send some message or if we want to retrieve some information from internet we make use of TCP/IP protocols. Your request is transferred over the network, which first goes to the DNS server. This server stores all the domain name and their Ip addresses to find the target server so that it can fetch the information that the user wants. Ones the target server is identified, the request is sent to that server and the response of that will be transmitted to the node which has requested the information. Internet is so flexible that it will take any connecting route to deliver the information.

Now we will take a look at how actually the data is transferred over the internet.

To retrieve an article, the computer had to connect to the server which was storing this article. We will now use this example to explain the flow of data over the internet.

First, you open your browser and type the domain name of the website you want to visit. Then This request is sent to ISP further Isp sends this request to the DNS server. DNS server then tries to match your Domain name to the domain names stored on that server. when DNS server finds the match it gives the IP address of the server where the data is stored. If suppose the DNS server fails to match the domain name then it sends it further for matching.

Finally, this request will come to the server where the data was stored. Now this server will respond by sending the requested data in the form of packets.  Each packet is of some size and has the data which is requested and also the header footer containing the information of what is there in the data andt the destination of that packet, it also has the information of how all the packets can be combined to form an entire file. Each packet then travels from the network to reach your computer, it may so happen that all the packets may come from different routes. They take the path which has the least traffic.

When the receiver receives the packets, it then try to connect this packets together to form an entire file. It may so happen that some of the packets may have been destroyed on the way, if this is the case then server again requests for that packet again. When entire file is compiled you see the result on your computer by opening the requested site for you. This is the way how data is moved over the internet.

This is how the Internet works for you in microseconds. If you take a deeper look at the various nodes, Components and different protocols that are used over the internet the picture becomes more complex for you. This article just gives you a broad view of highly complex Internet. To go deeper in this stay connected with me for my articles on computer network. Thank you.

About
Shrikrishna Parab is founder of The- ShreeOnTechnology. He is a researcher in the field of Computer Science and Technology. He is 25 and lives in Goa. You can Follow him on Twitter, Facebook and Google+.