User Guide
Welcome to the SimNet user guide! SimNet is a browser-based network simulator built for cybersecurity challenges (CTFs). Think of it as a "virtual network lab"—no installation required, just open the page and start experimenting.
The Three Main Areas of SimNet
The SimNet interface is split into three main areas, mirroring what you would see on a real security analyst's workstation:
Topology
The topology view visualizes the entire network architecture—which devices (computers, switches, servers) are connected to each other, and what their IP and MAC addresses are. Like looking at a city map, you can take in the whole picture at a glance.
It supports mouse zooming, drag-to-pan, and hover-to-inspect for details.
Traffic
The traffic panel displays every packet flowing across the network in real time—where it came from, where it's going, and which protocol it uses. It's like setting up a camera on a highway that records every car and its license plate as it passes.
It supports protocol filtering, keyword search, and expanding packets to see each layer's details.
Terminal
The terminal is where you actually "get your hands dirty." You can type commands here to inspect network settings, send packets, capture traffic, and even launch attacks—all inside a safe simulated environment. It behaves just like a real Linux terminal, but you can't break anything.
Go to Terminal command reference
What's Next
If this is your first time using SimNet, we recommend starting with Getting Started with SimNet and following the steps.
If you're already familiar with the basics, jump straight to the Terminal command reference to find the command you need.