NetLab

A desktop app for building and experimenting with network topologies using real Docker containers.

What is NetLab

NetLab lets students design a network topology visually — nodes, cables, switches — and have each element backed by a real, runnable environment: every node is a Docker container, every cable/link is a real Docker network. Students configure IP addresses, routes, bridges and firewall rules by hand, inside the actual container's shell, exactly as they would on real hardware — NetLab only handles the wiring, not the networking itself.

Features

• Visual topology editor — drag nodes onto a canvas, connect them with links, pan/zoom, resize the layout.
• Real containers, real shells — every node opens in your OS's native terminal (not an emulator embedded in the app), attached via docker exec.
• Multiple base images — Alpine, Debian, and Ubuntu, each pre-loaded with a full network toolset (iproute2, iptables, bridge-utils, tcpdump, ethtool, and more).
• Switch nodes — a node can bridge two links together (ip link add br0 type bridge), taught and built by the student; NetLab transparently works around a Docker Desktop quirk (hairpin mode) that would otherwise break it.
• Internet-facing nodes — a dedicated WAN bridge with NAT, for exercises that need outbound connectivity while the student still configures ip_forward/iptables MASQUERADE themselves.
• Self-healing — Docker resources NetLab owns (networks, custom images, orphaned containers) are detected and rebuilt automatically if something external interferes with them (e.g. docker network rm run by hand).
• Bilingual UI — Italian and English, switchable at runtime.

Requirements

• Docker (Docker Desktop on Windows/macOS, or Docker Engine on Linux), installed and running.

Installation

Download the installer for your platform from the Releases page:

• Windows — NetLab Setup x.y.z.exe
• macOS — NetLab-x.y.z.dmg
• Linux — NetLab-x.y.z.AppImage (self-contained — chmod +x it and run it) or netlab-app_x.y.z_amd64.deb (install with sudo apt install ./netlab-app_x.y.z_amd64.deb)

Make sure Docker is running before you launch NetLab.

NetLab isn't code-signed (that requires a paid certificate), so the OS will warn you the first time you run it — this is the same warning any unsigned app triggers, not something specific to NetLab:

• Windows: SmartScreen shows "Windows protected your PC". Click More info, then Run anyway. If it was blocked silently instead, go to Settings → Privacy & security → Windows Security → Virus & threat protection → Protection history to allow it.
• macOS: Gatekeeper refuses to open it ("cannot be opened because the developer cannot be verified"). Go to System Settings → Privacy & Security, scroll down, and click Open Anyway next to the NetLab message.
• Linux (AppImage): needs libfuse2 installed (sudo apt install libfuse2, or libfuse2t64 on newer distros) — without it the AppImage fails to mount and won't start. The .deb package doesn't have this requirement.

Getting started

See the user guide for a step-by-step walkthrough of building your first topology.

Development

See the developer guide for the project's architecture, how to run it locally, and how to build a release.