Engadget
The right Ethernet switch can add ports without slowing your network or saddling you with features you don't need.
If you're running out of Ethernet ports, that doesn't mean you need another router. If your Wi-Fi coverage is already working well, an Ethernet switch is the simpler option to connect more PCs, game consoles, TVs, network-attached storage and other wired devices.
Shopping for an Ethernet switch gets complicated quickly. Buying the one with the most numbers on the box doesn't mean it will be the best for you. The best approach is picking a switch that will accommodate your existing network and leave room for future devices.
The port count is the part, though there is a catch. Typically, you'll use one port to connect the switch to your router. If you need four more ports right now, an eight-port switch gives more breathing room for future devices.
If your internet connection, router and wired devices all max out at Gigabit speeds, then a 1GbE switch is reasonable. If you have multi-gig internet, a newer PC with 2.5GbE or a fast NAS with multi-gig networking, then a 2.5GbE switch makes more sense.
If the router has a 2.5Gbps port and the switch is limited to 1GbE, the traffic between the router and switch will be limited to 1GbE.
Two 10GbE-capable devices connected to the same 10GbE switch can move files across your local network much faster than your internet plan allows, which can matter for large NAS backups or video files.