In Part II, we learned how an HTTP request travels across the Internet to the correct destination server, through several layers, and returns with a response. But how does this happen reliably and securely, without becoming corrupted or being intercepted by a malicious hacker?
What exactly happens when you enter a URL in your browser? How does your browser know what content to display? To answer this question, we need to understand how the various layers of the Internet work.
ISPs, routers, gateways, LANs, HTTP, the cloud, the web… the Internet is so complex that we could spend days, months, and even years studying this stuff, and we still wouldn’t be done.