Networking Basics

Whether you are browsing a website, streaming a video, or sending a message on your phone, networking is happening behind the scenes. Understanding networking is essential for anyone involved in software development, system design, or cloud computing. This article explains the fundamentals of networking in  a clear, practical way.

What is Networking?

At its core, networking is the process of connecting computers, devices, and systems so they can communicate and share data.

• A network can be as simple as two computers connected via a cable or as complex as the global internet connecting billions of devices.
• Networks allow applications to exchange information, whether that's loading a webpage or sending a chat message in real time.

Without networking, web applications, mobile apps, and distributed systems wouldn't exist.

The Client-Server Model

The client-server model is the most common architecture for networked applications.

• Client: Requests information or services.
• Server: Provides information or services.

Example:

When you open Gmail in your browser:

• Your browser acts as the client, sending requests for your emails.
• Google's servers respond with the data, rendering your inbox.

This model is the foundation of most web and mobile applications today.

Communication Protocols

Protocols define the rules and standards for communication between devices. Some of the most important protocols include:

HTTP & HTTPS

• HTTP (Hypertext Transfer Protocol): Enables browsers to request web pages from servers.
• HTTPS: Secure version of HTTP using encryption (TLS/SSL)

DNS Server

The client need to know where the server is, it needs an address to locate and communicate with it.

Each computers on the internet is identified using IP addresses, it is unique to everyone, it works like an home address. Technically we can say an IP address is a unique numerical identifier for every device connected to a network. 

Problems with IP Addresses:

• Hard for humans to remember
• Number have no meaning (what is 142.250.190.78?)
• Change frequently (especially in cloud environments)

DNS: The “Phone Book” System

Domain Name System – the distributed database that translates names to IP addresses.

Think of it as the entire phone book system of the internet.

Instead of relying on hard-to-remember IP addresses, we use something much more friendly: domain names.

But, we need a way to map a domain name to it's corresponding IP address. This is where DNS (Domain Name System) comes in. It maps easy to remember names (like thejat.in) to their corresponding IP addresses.

How it works:

Human-Friendly Name → DNS Translation → Machine-Friendly IP
google.com          → DNS Lookup       → 142.250.190.78

Here's what happens behind the scenes:

1. When you type www.thejat.in in the browser, your browser asks a DNS server for the corresponding IP address.
2. Once the DNS server responds with the IP, your browser uses it to establish a connection with the server, and make a request.