TP-Link Deco mesh Wi-Fi system

What it is good at

• Covering rooms the single router never reached usefully
• Handing devices between units without dropping the connection
• Being managed from an app instead of a browser page full of menus

Check before you buy

• Whether each unit has enough wired ports for a desk and a console
• Whether the units can be joined by cable, which is the only way to keep full speed
• The app: some systems keep most settings behind an account and an internet connection

Who it is not for

A small flat where one router already covers every room, or anyone who wants a router they can flash with their own firmware.

A mesh system is several access points that share one network name and coordinate which unit answers a device. The handover is the engineering, because a phone that holds on to the wrong unit keeps a strong-looking signal and a slow connection.

The cost is the link between the units. Unless they are joined by cable, they talk over the same radio the devices use, so the second hop carries roughly half the throughput. Wiring the satellites is the single change that makes a mesh system worthwhile.