Zero install · runs in your browser

Browser-based CompTIA Network+ and Security+ training labs.

Learn networking by doing: no VMs, no Cisco licensing, and no install. Open a lab and start configuring in seconds.

NetForge is an independent UK-operated educational platform. Labs are browser-based simulations for personal study and exam preparation.

Free labs

Topics

£0

To start

Example output — subnet calculator

$ nf subnet 192.168.50.0/26

Network192.168.50.0 /26

Broadcast192.168.50.63

Hosts62 usable (.1–.62)

Mask255.255.255.192

Wildcard0.0.0.63

$ nf vlan 10 name SALES trunk Gi0/1

✓ VLAN 10 tagged — 802.1Q on Gi0/1

✓ Access ports Fa0/1, Fa0/2 assigned

No account requiredCompTIA-aligned

No VM required· No Cisco licence· No download· No payment· Every lab is free

Every lab, one click away.

Browse all 57 labs across 10 topics — every lab and exam practice feature is free, with no account or setup required.

01Fundamentals12 02Subnetting5 03Switching6 04Routing10 05Wireless7 06Security12 07Cloud2 08PowerShell1 09Troubleshooting1 10Training1

Fundamentals

Core protocols & concepts

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The OSI 7-Layer ModelBegFREE Network TopologiesBegFREE Access Control (CSMA/CD)BegFREE Cables & HardwareBegFREE Address Resolution (ARP)BegFREE Network Services (DHCP/DNS)BegFREE DNS Resolution VisualiserIntFREE Packets vs. FramesBegFREE Protocol Data UnitsBegFREE How Ping Works (ICMP)BegFREE TCP Connection LifecycleIntFREE Wireless-to-Wired PathIntFREE

Subnetting

IP addressing & VLSM

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IP Subnet CalculatorBegFREE VLSM PlannerIntFREE IPv6 Address BasicsIntFREE IPv6 Autoconfiguration: NDP, SLAAC & DHCPv6IntFREE Subnetting Quick SheetBegFREE

Switching

VLANs, STP & 802.1X

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What is a Switch?BegFREE MAC Learning & ForwardingBegFREE VLAN ConfigurationIntFREE Spanning Tree ProtocolIntFREE Link AggregationIntFREE 802.1X Network Access ControlAdvFREE

Routing

OSPF, BGP & NAT

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What is a Router?BegFREE Gateway & Backup RoutesBegFREE Longest Prefix MatchIntFREE NAT / PAT SimulatorIntFREE Routing Protocols MatrixIntFREE BGP Route Selection & PeeringAdvFREE OSPF VisualiserAdvFREE QoS Traffic ManagementAdvFREE IPsec / WireGuard VPNAdvFREE VPN Policy & MTU TroubleshootingAdvFREE

Wireless

Wi-Fi standards & security

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What is Wireless?BegFREE Wi-Fi Spectrum AnalyserIntFREE Cell Overlap & RoamingIntFREE BeamformingIntFREE Wi-Fi Security (WPA)IntFREE 802.11 StandardsBegFREE Enterprise Wi-Fi Design & RoamingAdvFREE

Security

Attacks & defences

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Layer 2 Attack MitigationAdvFREE ACL Rules SimulatorIntFREE TLS Handshake VisualiserIntFREE Firewall Zone PolicyAdvFREE PKI & Certificate ChainAdvFREE Network ForensicsAdvFREE Phishing SimulatorAdvFREE ARP Poisoning / MITMAdvFREE AAA & IdentityAdvFREE Stateful Firewall & NAT TroubleshootingAdvFREE Incident Response Evidence HandlingAdvFREE Zero Trust Access DecisionsAdvFREE

Cloud

Virtual networks & connectivity

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What is Cloud Networking?BegFREE Secure Three-Tier Cloud NetworkAdvFREE

PowerShell

Network diagnostics

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Diagnostics Command MatrixBegFREE

Troubleshooting

Find and fix faults

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Network TroubleshootingIntFREE

Training

Exam practice

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Exam Practice SandboxIntFREE

Learning that actually sticks

Interact, don't just read

Configure live VLANs, step through TCP handshakes packet by packet, watch OSPF's Dijkstra computation run in real time. The simulation is the lesson.

Instant, in-browser

No terminal, no VM, no Packet Tracer licence. Open a lab from any device in seconds.

Exam-objective mapped

Every lab references the exact CompTIA N10-009 or SY0-701 objective it covers.

All included. Free.

Every lab and mock exam is available at no cost. Sign in is optional and only needed to save progress across devices.

Built for CompTIA exam prep

N10-009CompTIA Network+

Networking Concepts	23%
Network Implementation	20%
Network Operations	17%
Network Security	20%
Network Troubleshooting	20%

Explore N+ labs →

SY0-701CompTIA Security+

General Security Concepts	12%
Threats & Vulnerabilities	22%
Security Architecture	18%
Security Operations	28%
Program Management	20%

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