How to add extra ethernet ports to your router and your network.
QUESTION I have a router that has 4 ports and I need to use ethernet on some computers further around the room. Can I add a device to make the single ethernet cable I have run over the other side of the room into more ports?
HELPROOM ANSWER Yes, this is very simple indeed. All you need is an ethernet switch with the required number of ports. Connect the long cable from your router into the uplink port of your switch and then you will be able to use the ports on the switch just as though they were extra ports on your router.
There are a few points to consider when choosing your switch: First of all, you'll need to ensure you have enough ports for all the devices you want to connect, plus one. The extra port being used to connect to your router. Also consider whether you'll likely to add any additional devices in the future. In general, the fewer the ports, the less expensive the switch.
Next you need to consider the speed of the switch. If your router has Gigabit ethernet ports, then you'll probably want a switch which also supports Gigabit speeds. Otherwise, you may be able to save some money by opting for a 100Mbit switch.
Another factor is power and noise. Larger switches can often include noisy fans which you really won't want whirring away continuously in your living room. For simple plug-and-play connections, look for auto MDI / MDIX which means you won't need to worry about using special cables or a specialised uplink port for connection to your router.
A managed switch will allow you to prioritise certain ports or types of network traffic, but for general home use you can go for a low-cost unmanaged switch.