When you’re short on ethernet ports and flirt with the idea of essentially turning one ethernet cable into two, the first thing that comes to mind is probably “ethernet splitting” – “splitting” the connection into two. But then you start looking into ethernet solutions and realise you have the choice between a hub, splitter and switch. These are actually slightly different things from each other, so you need to know which one best serves your purpose. Which one does which?
At the risk of sounding like a clickbait ad about weight loss, “the answer may surprise you.”
Let’s start with the thing that you were probably most tempted to just run out and buy when looking to turn one ethernet connection into several. (Hint: don’t do it!)
An ethernet splitter looks pretty unassuming. It’s a small gizmo with three ethernet ports on it – two on on side and one on the other. If you have a surplus of short ethernet cables kicking around and just one or two long ones, then this is where a splitter comes in handy. Crucially, note that an ethernet splitter doesn’t actually increase the number of devices you can connect via ethernet, and you will need a splitter at the other end to “unsplit” the connection back into two cables, so two ethernet splitters will be required each time.
Each pair of ethernet splitters only channels two cables because it relies on the fairly old 100BASE-T standard. 100BASE-T ethernet cables (like most Cat 5e cables) only utilise two of the four pairs of wires in the cable, and an ethernet splitter takes advantage of that by channelling two pairs of wires from each cable into all four pairs in one cable. Then, once you use that one cable to reach the room or devices you want, you plug it into another splitter and use the two remaining ports on that splitter to connect the devices. Note also that network speeds using a splitter are restricted to 100Mbps.
Returning to our original topic of turning one ethernet cable into two, the ethernet switch is the real star of this guide. The way it works is incredibly simple. Whether you have a four-port switch or an eight-port one, you use one port to connect the switch to your router via ethernet, then the rest into the other ethernet devices you want to connect. Effectively, one ethernet port becomes several.
Switches give the inbound data from your network devices their own pathways where the data between devices won’t interfere with each other. Switches allow for full-duplex communication between devices which means that data can be sent and received at the same time, resulting in a faster network. The great thing is that they’re not that expensive now either, as you can pick up one that is a good brand for around $15 or so.
Last and probably least is the ethernet hub which has been pretty much outmoded by the switch. If a switch creates pathways to precisely allow the packets sent from each device to communicate with your router, then think of a hub as a vast chamber filled with network traffic where packets go in and broadcast or shout to find the devices they’re trying to connect. In more technical terms, hubs cannot allow devices to send and receive data at the same time, which is called half-duplex communication.
This results in data holdups and collisions, hogging precious bandwidth and causing network slowdown, particularly when you’re using multiple devices simultaneously.
Note that ethernet hubs pretty much look exactly like switches, so don’t make the mistake of buying this when what you really want is a switch. Hubs are yesterday’s news.
With the above info, you should now know which of the ethernet thingymajigs you need for which purposes. Think of the ethernet switch as the “new” ethernet hub, while a splitter fulfills the more niche role of running a pair of cables “as one” over longer distances.