Networking

Have you ever asked, why do we usually listen on localhost:8080 during development process, can we listen on Google IP instead of localhost? I have a little code snippet written in NodeJS: 1 2 3 4 5 var http = require('http'); http.createServer(function (req, res) { res.writeHead(200, {'Content-Type': 'text/plain'}); res.end('Hello World\n'); }).listen(8080, 'localhost'); It doesn’t do anything complex, just starts a new server, listens on localhost:8080, and responds ‘Hello World’ to requests. I need you to do a little more thing, open your terminal, and execute this command (MacOS or Linux) to get your local IP: ...

So this is just a quick recap of what I have learned about networking First, you have to connect your computer to the local network. Your computer then will be assigned a local IP by a DHCP server (Dynamic Host Configuration Protocol), you cannot use that local IP to talk to the outside network. All the devices in the same local network will use the IP of the gateway to talk to the internet, sometimes it’s called public IP. The protocol to map from local address to public address is called NAT (Network Address Translation). ...