Free CCNA | OSI Model | Day 3 Lab | CCNA 200-301 Complete Course

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Published on Nov 25, 2025 This response is partially generated with the help of AI. It may contain inaccuracies.

Table of Contents

Introduction

This tutorial will guide you through the OSI model as demonstrated in Day 3 of the Free CCNA 200-301 course. Understanding the OSI model is crucial for networking professionals, as it provides a framework for understanding how different networking protocols interact. This lab focuses on examining network traffic to see the OSI model in action.

Step 1: Setting Up the Lab

To get started, you need to set up your lab environment. Follow these steps:

  1. Download and Install Packet Tracer

    • Visit the NetAcad website and download Packet Tracer.
    • Install the application on your computer.
  2. Open Packet Tracer

    • Launch the Packet Tracer application.
  3. Create a New Project

    • Start a new project by selecting 'File' and then 'New'.
  4. Add Devices

    • Drag and drop the following devices onto the workspace:
      • 2 PCs
      • 1 Switch
    • Connect the PCs to the switch using copper straight-through cables.
  5. Configure the Devices

    • Assign IP addresses to the PCs.
      • PC1: 192.168.1.1 /24
      • PC2: 192.168.1.2 /24
    • Ensure both PCs can communicate with each other on the same network.

Step 2: Initiating Network Traffic

Now that your lab is set up, you will generate and observe network traffic. Follow these steps:

  1. Ping Test

    • On PC1, open the command prompt.
    • Type ping 192.168.1.2 and press Enter.
    • Observe the results. Successful replies indicate that the devices are communicating.
  2. Use Packet Tracer Simulation Mode

    • Switch to simulation mode in Packet Tracer.
    • Initiate the ping command again to see the packets being sent across the network.
    • Click on the packets to view details.
  3. Analyze the OSI Layers

    • As you examine the packets, notice how they relate to the OSI model:
      • Layer 1 (Physical): Physical connection details.
      • Layer 2 (Data Link): MAC addresses.
      • Layer 3 (Network): IP addresses and routing information.
    • Understanding these layers will help you troubleshoot and design networks effectively.

Conclusion

In this lab, you successfully set up a basic network, generated traffic, and observed how data flows through the OSI model. This hands-on experience is invaluable for grasping networking concepts.

Next Steps

  • Review the OSI model in your CCNA study materials.
  • Experiment with different configurations in Packet Tracer.
  • Continue with the next lessons in the CCNA course to deepen your understanding of networking principles.