Beginner to advanced · No install · Free account opens Module 1

Build, configure, and simulate networks — in your browser.

NetForge-AI is an interactive packet-level network lab with a networking course led by AI. Drag in routers, switches, PCs, and servers. Configure them with an industry-standard CLI. Watch ARP, ICMP, DHCP, and routing decisions unfold live across cables.

Browse the networking courseOpen the lab

Built for students, instructors, and engineers learning networking from beginner to advanced. Now with ARIA — your AI tutor leading every chapter.

Animated demonstration: a student asks ARIA, the AI tutor, to build a network topology in plain English. ARIA generates the devices and cables on the lab canvas, configures them, and verifies connectivity with a ping — looping through several example networks.

Features

Everything you need to actually understand a network

No quizzes. No memorization. NetForge-AI teaches by letting you build broken topologies and watch them fail — then fix them, hop by hop.

Drag & wire

Drop devices on an infinite canvas, click two ports to lay a cable. Cable type auto-resolves: copper, fiber, serial, or wireless.

Industry-standard CLI

A familiar EXEC, privileged, and config mode. hostname, interface, ip address, no shutdown, ip route, show running-config — all working.

Live packet animation

Every ARP, ICMP, and DHCP frame is rendered as a glowing dot traveling the cable. See exactly which port floods and which forwards.

L3 routing

Connected, static, and default routes. Longest-prefix match, hop-by-hop tracing, TTL exhaustion, and routing-loop detection — all visualized.

Switch fabric

MAC learning, flooding-vs-forwarding, VLAN tagging, broadcast domains, and ARP-resolved unicast paths.

Topology I/O

Save and load topologies as JSON files. Share a complete lab with classmates in one click. Three example labs ship in-app.

How it works

Four steps. No setup. No license.

A free account opens the lab and Module 1. No download, no card — just sign up and start building.

  1. 01

    Drop devices onto the canvas

    Routers, L2/L3 switches, PCs, servers, hubs, access points, and a WAN cloud — each with realistic interface counts.

  2. 02

    Wire ports with one click

    Click a port on device A, click a port on device B. Cables auto-pick the right media for the interface kind.

  3. 03

    Configure with GUI or CLI

    Set IPs from the side panel, or drop into the network device CLI: configure terminal, interface gi0/0, ip address …, no shutdown.

  4. 04

    Run traffic and watch it travel

    ping from any device. Frames animate across cables. ARP and MAC tables fill in. Routing decisions log live.

Protocol coverage

The OSI stack — visible, inspectable, and breakable

NetForge-AI is intentionally designed as a teaching tool. Every protocol it implements is logged step by step, so you can see why a packet was dropped or which route was chosen.

Physical / L1

  • Copper Ethernet
  • Fiber
  • Serial WAN
  • Wireless 802.11

Data Link / L2

  • MAC learning & aging
  • VLANs (access/trunk)
  • Spanning Tree (STP/RSTP/PVST+)
  • EtherChannel (LACP/PAgP)
  • ARP request/reply

Routing / L3

  • IPv4 addressing & subnetting
  • Static & default routes
  • OSPF (DR/BDR, cost)
  • EIGRP (bandwidth+delay metric)
  • RIPv2
  • BGP (eBGP & iBGP)

Services & security

  • DHCP server pools
  • VRRP first-hop redundancy
  • NAT (static / pool / PAT)
  • Standard & extended ACLs (L4 ports)
  • ICMP echo / time-exceeded
Who it's for

Built by network engineers, for everyone learning

Students learning networking

Work through an 8-module networking curriculum that takes you from beginner to advanced: 47 chapters, 104+ practice questions, hands-on labs, and a 60-question final assessment. Module 1 is part of the free plan; modules 2–8 unlock with Pro.

Instructors running labs

Save a topology, distribute the JSON, students load it locally. Give graded scenarios with broken configurations — let them fix it.

Engineers prototyping designs

Sketch an IP plan and validate routing logic in minutes. NetForge-AI is a fast, lightweight whiteboard for L2/L3 conversations.

FAQ

Frequently asked questions

What is NetForge-AI?+
NetForge-AI is a browser-based network simulator and networking course for learning routing, switching, and core IP protocols from beginner to advanced. Drag virtual routers, switches, and PCs onto a canvas, configure them with an industry-standard CLI, and watch packets animate across the topology in real time.
Is NetForge-AI a browser-based network simulator?+
Yes. NetForge-AI covers the core networking topics learners practice — IP addressing, subnetting, VLANs, ARP, ICMP, static routing — and runs entirely in the browser. It is independently developed and not affiliated with any networking vendor or certification body.
Do I need to install anything?+
No. NetForge-AI is a web app. Anyone can browse the course syllabus without an account; reading chapter content and using the lab requires a free account (no card needed).
Which protocols are simulated?+
NetForge-AI simulates Layer 1 cabling (copper, fiber, serial, wireless), Layer 2 switching with MAC learning, VLANs and 802.1Q trunks, Spanning Tree Protocol (STP/RSTP/PVST+) with real root-bridge election, and EtherChannel (LACP/PAgP). At Layer 3 it runs IPv4 static and default routing plus four dynamic protocols — OSPF with DR/BDR election, EIGRP with the bandwidth-and-delay composite metric, RIPv2, and BGP (both eBGP and iBGP). It also models VRRP first-hop redundancy, NAT (static, dynamic pool, and PAT/overload), standard and extended ACLs with Layer 4 TCP/UDP port matching, ARP, ICMP, and DHCP server pools.
Can I save and share my topology?+
Yes. The Save button exports your full topology — devices, interfaces, IPs, routes, links — as a JSON file. Anyone with NetForge-AI can load it with the Load button.
Is this suitable for building real networking skills?+
NetForge-AI covers core networking topics in switching and IPv4 routing, taking you from beginner to advanced. It is great on its own and pairs well with any study guide, giving you hands-on practice that mirrors real-world configuration tasks.
Does NetForge-AI cost anything?+
There are two tiers. The Free plan (with a free account) unlocks Module 1 of the networking course, the lab with up to 5 devices, and 3 saved topologies — no card required. Pro is $29.99/mo (or $299/yr) and unlocks all 8 modules, the final assessment, unlimited lab and saves, and the ARIA AI tutor — a hosted cloud assistant in both the lab and course chapters.

Stop reading about networks. Start building them.

The lab is one click away. Your first topology takes 30 seconds.

Open the lab
NetForge-AI — Interactive Network Lab, Beginner to Advanced