The scenario
PC-A (192.168.10.10/24) and PC-B (192.168.10.20/24) are plugged into Switch-1. Both addresses fall inside the same network, 192.168.10.0/24, so each PC treats the other as a neighbour it can reach directly. No router or default gateway is needed, and this lab has none. The switch passes Ethernet frames between its ports by MAC address; it never looks at the IP addresses inside them.
What you will work out
Understand how two hosts on the same subnet reach each other through a switch.
Why this matters
Every office LAN, home network and data-centre rack starts here: devices on one subnet, joined by switches, finding each other with ARP. When two devices on the same switch cannot talk, the first checks are the ones in this lab: does each have an address, are both addresses in the same subnet, and does the destination answer ARP.
Running it
Two Hosts And A Switch opens on a canvas, already wired and addressed. Trace a packet through it hop by hop, or run the same topology live on real Linux network namespaces. How the two modes differ.
Open Two Hosts And A Switch
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