Every time we send a message, open a webpage, or stream a video, we're relying on a massive system of networks known as the Internet. But what really happens behind the scenes? This lesson introduces the structure of the Internet, how websites are hosted, how domain names work, and how networks are organised using different models.
Learning Objectives:
Explain the difference between the Internet and the World Wide Web.
Understand the role of DNS, hosting, and cloud computing.
Distinguish between client-server and peer-to-peer network models.
Evaluate when each network model is suitable.
Terminology:
Internet: A global network of interconnected devices.
World Wide Web (WWW): A system of linked web pages accessible via the Internet.
DNS (Domain Name System): Translates domain names into IP addresses.
Hosting: Providing web storage and access to online content.
Cloud Computing: Storing and accessing data/services over the Internet.
Client: A device that requests services or resources.
Server: A central device that manages network resources and services.
Client-Server Model: A structured network with central management.
Peer-to-Peer (P2P): A network where all devices share resources equally.
The Internet is not the same as the Web. The Internet is the infrastructure—a network of networks. The Web is one of the services that runs on it, consisting of websites and pages linked via hyperlinks. When you enter a website address, DNS translates it into an IP address so that your device can connect to the correct server.
Web hosting companies provide the servers that store website data and serve it to users 24/7. Cloud computing allows people to store files or run software without relying on their own devices. The files are stored in massive data centres and accessed via the Internet.
Networks are also structured using models. In client-server setups, the server handles all requests. This is ideal for businesses and schools. In peer-to-peer models, each device can send and receive data without needing a central server—useful for small networks or file sharing.
Engaging Example: Imagine you’re watching Netflix. You're accessing data stored in a remote data centre. Netflix uses DNS to direct you to the right server. The whole process takes less than a second, yet it relies on several layers of the Internet, protocols, and DNS requests to work.
Common Mistakes:
Confusing the Internet with the Web.
Believing that all devices on a network need a server.
Thinking DNS stores the actual website content.
Revision Summary:
The Internet is the infrastructure; the Web is one service on it.
DNS converts URLs into IP addresses so devices can communicate.
Client-server networks are centralised; peer-to-peer networks are decentralised.
Cloud services and hosting allow for remote access to data and websites.
Comprehension Questions:
What is the difference between the Internet and the World Wide Web?
What role does DNS play in accessing websites?
What is web hosting?
Name one benefit of cloud computing.
What is a client-server network?
How does peer-to-peer networking differ from client-server?
Why might a school choose a client-server model?
What kind of IP address does DNS provide?
How does cloud computing help users access data remotely?
Give one disadvantage of using a peer-to-peer network.
Individual Activity: Draw a diagram of how a browser accesses a website. Include steps like DNS lookup, IP address resolution, and server response.
Pair Activity: With a partner, role-play a client-server interaction: one person is the client making requests, and the other is the server responding. Switch roles.
Small Group Activity: Debate: Should your school use peer-to-peer networking to save money? One side argues for cost and ease, the other for management and security.