Understanding the process of Data Transfer using a real-life example

In our day-to-day activities, we tend to transfer our data (information) from one device to the other. Data can be in the form of images, videos, information over phone calls, and accessing the web browser. Ever wondered how this happens? Let us understand it with the help of an example we can all relate to.

We use a lot of e-commerce websites for purchasing products. Let us consider buying a pair of shoes. We order them on any of the e-commerce websites. Firstly, the shoes are packed in a box for shipping. This box is then loaded onto the truck for the delivery of the product to our home address. The truck, obviously, uses roads for transportation.

Now let's connect the above example with the concepts of Computer Networks. The pair of shoes that were purchased can be thought of as the data to be transferred. The truck used can be thought of as the Internet Protocol, otherwise called, the IP. The truck uses roads, similarly, the IP uses some mode of transportation, technically called Network Topology. Some of the examples of the Topology are Ethernet, cable systems, etc. So, if summarizing, it would be as follows. The data to be transferred is to be put on the IP and the IP uses some form of Network Topology.

When we use a website, we are the clients and we constantly communicate with the web server and the data transfer occurs. There are basically, two types of data transfer:

1. Transmission Control Protocol (TCP)

2. User Datagram Protocol (UDP)

The TCP also called Connection-oriented protocol, is a type of data-transfer technique in which the sender of the data can keep a check on whether the receiver has received the data at the other end. In this type of protocol, we can be assured of complete data transfer from one system to the other. If data is not received at the other end, then the TCP will send the data again until the data gets transferred. It is a "Reliable" delivery mechanism.

In the case of the UDP, it is contrary to TCP, there is no such-response mechanism between the sender and the receiver. There is no assurance over the data transfer.

In simple words, in TCP, the sender sends the data and cares whether the data is received or not, but in UDP, the sender only sends the data without any clue whether the data is getting received on the other end. We can understand it with the image below.

We TCP, for web browsers, because we need to load the websites in the complete form without any error, if any data is missing, TCP will take a while and load it. UDP is used for phone calls because on phone calls, we have to transmit live data or information, if the information is not received at the other end, we have to ignore that particular data and let the new data transfer.

Hence, understanding these mechanisms gives us a brief outlook on how the data is being transferred from one device to the other.

Image source: https://cdnpractice.geeksforgeeks.org/problems/tcp-vs-udp