Below interactive educational visualizer for the TCP Three-Way Handshake — the process computers use to establish a network connection before exchanging data. It lets you step through all 3 stages one by one (SYN → SYN-ACK → ACK), showing an animated packet traveling between a Client and Server, while explaining what’s happening at each stage:

If you choose Send a Packet, you can simulate sending a packet in the Packet Simulator block. You can choose the source and destination PC where the packet will be sent. To see every step, you have to click Next Step, which is at the very bottom of the app.

A simple interactive tool for building subnet masks bit by bit. Click each of the 32 bits to toggle between 1 and 0 — the subnet mask in decimal, CIDR notation, and usable host count update instantly. Quick preset buttons let you jump straight to the most common masks like /24 or /16. If you

What is a subnet mask and why should you care? Every device on a network has an IP address — but an IP address alone isn’t enough. Your device also needs to know which part of that address identifies the network it belongs to, and which part identifies itself. That’s exactly what a subnet mask

A visual explanation of how IP addresses work in a home network — from your devices all the way to a remote server. The diagram covers private and public IPs, why your router has two of them, how NAT translation works under the hood, and what actually happens step by step when your PC sends

Encapsulation is the process of wrapping data from a higher layer inside a protocol at a lower layer. Each layer adds its own header (and sometimes trailer) to ensure proper delivery and interpretation at the destination. Each layer depends on the layer below it: without the lower layer functioning, the higher layer cannot be transmitted.

DNS caching is a system that stores frequently requested queries for a limited time (controlled by TTL). The cached data is kept as resource records (RRs), which conceptually have four main fields: An interactive HTML app to see how it works.