If you want to learn a little bit more about the communication between a web browser and an HTTP server, why not build your own web server and take a closer look.
Programming your own web server might seem like a difficult and unnecessary undertaking. Any number of freely available web servers exist in the Linux space, from popular all-rounders like Apache or NGINX to lightweight alternatives like Cherokee or lighttpd (pronounced “lighty”).
But sometimes you don’t need a full-blown web server. If you just want to share a couple of HTML pages locally on your own network or offer people the ability to upload files, Linux on-board tools are all it takes. A simple shell script is fine as a basic framework that controls existing tools from the GNU treasure chest. Network communication is handled by Netcat , aka the Swiss army knife of TCP/IP.
With a project like this, the best place to start is at the root. Because a web server is still a server at the end of the day, it needs to constantly listen on a given port and respond appropriately to requests. Usually, web servers listen on port 80 for normal requests, and port 80 generally only accepts HTTP requests without encryption. The web server I’ll describe in this article listens on ports 8080 and 8081 and communicates without encryption. If you are using a firewall and want to test the server on the local network, remember to allow these two ports in the firewall.
Use Express-Checkout link below to read the full article (PDF).