Network devices and topologies
Every device on a network has a clear job. Here is Nakhla's head-office network:
| Device | What it does | Works with |
|---|---|---|
| Network card (NIC) | Connects a device to the network; has a unique MAC address. | MAC |
| Switch | Connects devices inside one LAN and forwards data only to the intended device. | MAC |
| Router | Connects different networks and picks the best path for data, like the home router linking you to the internet. | IP |
| Access point (AP) | Lets wireless (Wi-Fi) devices join the wired network. | Wi-Fi |
| Firewall | The gatekeeper: allows or blocks traffic based on rules. | Rules |
| Modem | Converts the provider's signal (fibre, 5G or DSL) into data your network understands. | ISP |
A MAC address is like a car's chassis number: burned into the network card and written in hex, like 3C:52:82:1A:9F:04. An IP address is like a street address: it changes with the network you join.
A topology is the shape in which devices are connected:
Watch outMost companies today use a star: every device connects to a switch. If one device's cable fails, the rest keep working. Mesh is used between critical routers so that if one path breaks, another exists.