Article in English: When setting up a LAN, you'll need to know how many computers will be connecting to the network via Ethernet. This will determine the number of ports you'll need. If you have four or less computers that you need to hardwire, you'll just need a router. If you have more than four, you'll likely need to get a switch to extend the number of ports available on your router. If you want to allow devices to connect wirelessly, you'll need a router that can broadcast a wireless network. Most routers you'll find at the store or online have wireless capabilities. Network switches do not allow wireless devices to connect, and can only be used for hardwired LANs or to extend the number of ports available to the router. If you want all of the connected devices to have access to the internet, you'll need a router to handle the connections. If you don't need the devices to have a network connection, you can just use a network switch. This isn't much of an issue in most homes, but network cables cannot run longer than 100m (328 ft). If you have to run cable farther than this, you'll need switches in between. If you're filling all of the ports on your hardware, consider future-proofing to allow for more devices in the future.

Summary in Vietnamese:
Đếm số máy tính cần kết nối. Quyết định có tạo mạng không dây hay không. Quyết định các thiết bị trong mạng có được truy cập internet hay không. Tính toán khoảng cách giữa các thiết bị được nối dây. Cân nhắc nhu cầu trong tương lai.