Learning Objectives

By the end of this chapter, you should be able to:

• Explain what the Internet is and how it works at a high level.
• Understand how devices communicate over networks.
• Describe the journey of data from your device to a remote server and back.
• Define packets, frames, bandwidth, latency, throughput, and jitter.
• Explain why protocols are essential for communication.
• Understand the roles of ISPs, routers, switches, DNS, and servers in internet communication.
• Connect these concepts to real-world DevOps, cloud computing, Docker, Kubernetes, and CI/CD systems.

Introduction

Every day, billions of people use the Internet to browse websites, send emails, stream videos, join video calls, and deploy applications to the cloud.

When you type a URL into your browser, the page appears within seconds—but behind that simple action is a remarkable chain of events involving networks, protocols, routers, switches, DNS servers, and web servers spread across the globe.

As a DevOps engineer, you won't just use the Internet—you'll build, deploy, monitor, and troubleshoot systems that depend on it. Understanding how data moves across networks is therefore a fundamental skill.

This chapter explains what the Internet is, how computers communicate, and how a single request travels from your device to a remote server and back.

What Is the Internet?

The Internet is a global network of interconnected computer networks that communicate using the TCP/IP protocol suite.

Instead of being one massive network owned by a single organization, the Internet is made up of thousands of smaller networks connected together. These include: