Communication Over the Internet
Before we dive deeper into the course, let's study some key concepts to understand how communication over the Internet works
We'll cover the following...
What Is a Protocol?
An Analogy
Let’s start with an analogy. Think of your routine conversations. They usually follow a general pattern dictated by predefined rules. For example, most conversations start with greetings and end with goodbyes. They probably go something like this:
Turns out that end systems also follow such protocols to communicate with each other effectively on the network.
Formally, according to the Oxford Dictionary, a protocol is “a set of rules governing the exchange or transmission of data between devices.” In the next few chapters, we’ll study several network protocols in detail.
TCP
The Transmission Control Protocol (TCP) is one such protocol. It was created to allow end systems to communicate effectively. The distinguishing feature of TCP is that it ensures that data reaches the intended destination and is not corrupted along the way.
UDP
The User Datagram Protocol (UDP) is also one such key protocol. However, it does not ensure that data reaches the destination and that it remains incorrupt.
HTTP
HyperText Transfer Protocol (HTTP) is a web protocol that defines the format of messages to be exchanged between web clients, e.g., web browsers and web servers and what action is to be taken in response to the message. The World Wide Web uses this as its underlying protocol.
Packets
Now that we’ve established that end systems communicate with each other based on set protocols, let’s discuss how they actually communicate. Computers send messages to each ...