1. Unit 4, Lesson 11 How Data Travels the Internet AOIT Principles of Information Technology

2. The Internet Is the World’s Largest Computer Network Does this artist’s interpretation of the Internet remind you of anything? The Internet is a vast network of linked computers.

3. All Data Travels the Internet as Packets HeaderSender’s IP address Receiver’s IP address Protocol Packet number PayloadData TrailerData to show end of packet Error correction Email Packet Every web page that you view or file that you receive over the Internet comes as a series of packets. The chart on the right shows the breakdown of a generic email packet.

4. Most People Connect to the Internet With a LAN A LAN diagram, showing IP addresses and how each computer connects to the Internet

5. Each Device on the Internet Has an IP Address Every device on the Internet has an IP address. This control panel shows a computer’s IP address. Can you find your computer’s IP address?

6. Data Packets Travel Many Steps Between ISPs Packets take many “hops” to reach their destinations.

7. “Ping” a Computer to Check Your Connection Pinging a computer can tell you if your connection to the other machine is working.

8. The Internet Is Complicated Yet Effective The Internet uses a complicated yet highly effective system for sending data. Every day, billions of packets travel the Internet delivering data to millions of users around the world.

9. Image Credits The artist’s representation of the Internet on Slide 2 is available at http://en.wikipedia.org/wiki/Image:Internet_map_1024.jpg and is reproduced here under the terms of the Creative Commons Attribution 2.5 License. http://en.wikipedia.org/wiki/Image:Internet_map_1024.jpgCreative CommonsAttribution 2.5