Data communication and OSI layer Model

  . 🖥️ 1. What is TCP/IP? TCP/IP (Transmission Control Protocol / Internet Protocol) is a set of communication protocols used to connect computers and devices over the internet or local networks. It defines how data is packaged, addressed, transmitted, routed, and received from one device to another. TCP/IP is the foundation of modern networking and is used by all internet-based applications (like websites, emails, YouTube, etc.). 🌐 2. Why Do We Need TCP/IP? Without TCP/IP: Devices would not understand each other’s data There would be no standard format for communication Internet services would not function TCP/IP solves this by providing a universal communication language for all connected devices. 🧱 3. Layers of TCP/IP Model TCP/IP is divided into 4 layers , each with a unique function: 🔹 a. Application Layer Closest to the user Interacts with software applications (browsers, email apps) Protocols: HTTP, FTP, SMTP, DNS 🔹 b. Transport L...

  🌐 Introduction Have you ever wondered how your WhatsApp message or an email reaches from your device to someone else's device across the world? Behind this communication lies a well-structured system called the OSI Reference Model . OSI (Open Systems Interconnection) is a conceptual framework used to understand and design how data travels from one computer to another over a network. 📘 What is the OSI Model? The OSI Model was developed by ISO (International Standards Organization) in 1984. It consists of 7 layers , each responsible for a specific function in data communication. Full Form: OSI – Open Systems Interconnection Type: Conceptual (Theoretical) model Purpose: Standardize communication between different systems 🧱 7 Layers of the OSI Model (Top to Bottom) 1. Application Layer (Layer 7) This is the layer closest to the end-user. It provides network services directly to user applications like browsers and email. Functions: ✅ Web browsin...

✍️ Introduction: The Internet is the largest and most powerful network in the world. It connects millions of devices globally, enabling communication, data sharing, research, social interaction, and business. But what really is the internet? Let’s break it down in simple terms. --- 🌐 What is the Internet? The Internet is a global network of interconnected computers and servers that communicate using standardized protocols like TCP/IP. It allows users to: Access websites and online services Send emails and messages Stream videos, play games Use cloud storage Access real-time information Example: When you open Google.com, your device connects to Google’s server via the Internet, fetches the page, and displays it in seconds. --- 🎯 Key Features of the Internet: 1. Global Connectivity – Links the world together 2. Decentralized System – No single owner 3. Multimedia Access – Text, video, audio, images 4. Always Growing – Billions of websites 5. Supports Many Services – Web, email, file sh...

After this sessions you are able to understand these topics: What is OSI Model? What is 7 layers and its function? Real- life example (e.g, Post office or WhatsApp. Diagram. 🌐 What is OSI Model? (Open Sy stems Interconnection Model) The OSI Model (Open Systems Interconnection Model) is a theoretical framework developed by ISO (International Organization for Standardization) that helps us understand how data travels from one computer to another over a network . 🌐 OSI Model Using Trick: "Aaj Phir Se Test Nahi Dena Padega" “ To remember the 7 layers of the OSI model from  top to bottom (Layer 7 to 1) , use this simple Hindi sentence: Aaj Phir Se Test Nahi Dena Padega” Each word stands for one layer: Aaj → Application Layer This is the topmost layer. It allows the user to interact with network applications like Gmail, WhatsApp, or Google Chrome. Phir → Presentation Layer It formats the data, encrypts or compresses it so that the receiver can understand it prop...