How Does The Internet Work?

TLDR: Routers Moving Packets According To Various Protocols

Steven Li
Steven Li
Aug 1, 2017 · 12 min read
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Visualization of the Internet. Source:

How does the Internet Work?

What’s a protocol?

What’s a packet?

What’s a packet routing network?

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Command-line utility traceroute showing all the hops between my computer and google’s servers

Where did these Internet routers come from? Who owns them?

Do the packets always arrive in order? If not, how is the message re-assembled?

Do packets always make it to their destination?

What do these Internet addresses look like?

How can there be over 8 billion networked devices on the Internet if there are only about 4 billion IPv4 addresses?

How does the router know where to send a packet? Does it need to know where all the IP addresses are on the Internet?

Network Prefix: 129.42
Host Identifier: 13.69

But a router still needs to know a lot of network prefixes . If a new router is added to the Internet how does it know how to handle packets for all these network prefixes?

How do networked computers figure out ip addresses based on domain names?

How do applications communicate over the Internet?

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What do each of these Internet layers do?

What’s a client versus a server?

How can sensitive data like credit cards be transmitted securely over the Internet?

What is SSL/TLS?

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The web server is SSL-enabled. The browser can connect to it over https to ensure that communication is encrypted. The browser is also confident it is communicating with a real server, and not a man-in-the-middle.

How does SSL authenticate the identity of a server and encrypt their communication?

What happens if a hacker intercepts an SSL-encrypted session?


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