Build a topology with routers, switches, MikroTik devices, Wi-Fi and PCs. Configure them with real-style CLIs, then watch every packet travel hop by hop.
1. Build. Drag devices from the left onto the workspace (or tap a device, then tap the workspace).
2. Cable. Choose Cable, click the first device, pick a port, click the second device and pick its port. Wi-Fi needs no cable: set the same SSID and password on the client and the access point and keep them close together (the dashed ring shows the range).
3. Configure. Double-click a device. Config is the graphical setup; CLI is a real command line: Cisco IOS style for routers and switches (enable, configure terminal, show ip route, ? and Tab help), RouterOS style for MikroTik (/ip address add address=192.168.88.1/24 interface=ether2), and a command prompt on PCs (ipconfig, ping, tracert, nslookup, curl, telnet).
4. Test. Use Send packet (click source, then destination), or ping from any CLI. In Simulation mode every hop pauses so you can step through ARP, ICMP, DHCP, DNS and HTTP.
Learning tools: Activity scores goals for a lab (tutorial labs in Labs come with goals). Quiz builds questions from your topology. Click any row in the Event list to open the packet inspector (OSI layers). With the Inspect tool, click a cable to run a cable test. Share copies a link to your lab; Import builds a lab from text. In Packets sent you can save and replay packet scenarios.
What is simulated: Ethernet switching with MAC learning, VLANs and trunks, ARP, IPv4 routing (static, RIP and OSPF-style), router-on-a-stick, Layer 3 switch SVIs, DHCP with relay, DNS, HTTP, ACLs, NAT/PAT and port forwarding, MikroTik bridges, firewall and Wi-Fi. Simplifications: no spanning tree, no IPv6 and no real packet timing.
More Packet Tracer-style tools. Complex PDU (X) sends ICMP, TCP or UDP packets with your own ports, TTL, count and an optional repeat. Draw (S) adds rectangles, ellipses and lines you can move, resize and recolour. Rename a cluster with the ✎ button on its label, or right-click the collapsed icon. Tick Console required to make routers and switches open only through a PC Terminal. Pick Console in the cable list to link a PC to a router or switch, then open the PC's Terminal tab. Hold Shift and click or drag to select several devices, then press Cluster to fold them into one icon (double-click it to open it again).
Your work is saved automatically in this browser. Use Save to download it as a file. Shortcuts: V select, C cable, P send packet, I inspect tables, Ctrl+Z/Ctrl+Y undo/redo, N note, D delete, Esc cancel.
Each cell is one ICMP echo from the row host to the column host. Green = reply, red = failed (hover for the reason).
One command per line. Types: router, switch, l3switch, pc, laptop, server, ap, hub, mikrotik… (see the palette names).
Repeat sends the packet again every few seconds until you press Stop in the Packets sent tab. A small TTL lets you see where a packet dies.
