Concluding that an "Ethernet splitter" is the best solution for splitting an Ethernet cable is an easy mistake to make.
The scenario which leads to this conclusion may even be how you found this article. You wanted to split an Ethernet cable to connect to two different computers or devices, so you searched for an "Ethernet splitter." You may have even found some products advertised as Ethernet splitters. They do exist. However, they are not the ideal tool for the job.
This article will explain what an Ethernet splitter is and why you probably want an Ethernet switch or hub instead. I'll also show you my recommended Ethernet switches in the section below.
I've seen two different types of products marketed as Ethernet splitters. They are both hacks and not supported by any Ethernet specifications.
First, note that Ethernet cables contain four twisted pairs of wires, with eight wires total.
For our examples below, we'll consider three devices that you want to connect: A, B, and C.
Hard-Wired Ethernet Splitter
For the first type of Ethernet splitter, which we'll call a hard-wired splitter, device A is on one end of the splitter, and B and C are on the other end of the splitter. In this case, all of the wires for B and C are shared.
It splits all four twisted pairs of wires into two directions, with both directions sharing the same electrical connection.
However, Ethernet communication doesn't allow for more than two devices to communicate on a single cable. Due to this, the product descriptions indicate that you can only connect one device at a time.
This sort of contraption works if you have only one of either device B or device C powered on at a given time. A hard-wired splitter could prevent you from having to unplug the Ethernet cable from one device (B) to plug it into the other (C). For example, this might work for switching from one game console to another if the other console and its Ethernet adapter are entirely powered off.
Drawbacks of a Hard-Wired Ethernet Splitter
A hard-wired Ethernet splitter's critical drawback is that it doesn't allow you to connect additional devices (you can only connect one at a time). This drawback seems pretty important, as this feature is what people searching for an Ethernet splitter are typically looking for!
Additionally, even if you unplug device A and plug devices B and C in, devices B and C will not communicate due to improper wiring. Devices B and C would have a straight-through connection, which many network adapters won't support. In this regard, the "split" is only in one direction.
Split-Pair Ethernet Splitter
We'll call the second type of splitter a split-pair Ethernet splitter.
You must use a split-pair Ethernet splitter type in pairs (two adapters). It converts a single Ethernet cable into two joined cables.
So, for example, you might have an Internet router (A) that connects to two ports of one end of the splitter and two computers (B and C) which connect to the other end.
These Ethernet splitters direct two pairs of twisted wires to one connector and the other two twisted pairs to a second connector. The split-pair Ethernet splitter effectively produces two cables that use half as many wires as modern Ethernet cables are intended to use.
The split-pair Ethernet splitter is closer to what most people think they want when searching for an "Ethernet splitter." Compared to the hard-wired Ethernet splitter, at least this type of connector allows you to connect an additional device!
Drawbacks of a Split-Pair Ethernet Splitter
This type of splitter has a variety of drawbacks:
- With only two of the four pairs used for each connection, the connection can only support a maximum of 100 Mbps.
- Due to improper use of the twisted pairs, cross-talk can not be prevented, resulting in signal interference and reduced data rates (lower than 100 Mbps).
- Unless one of the two splitter adapters is connected to a router, hub, or switch, the devices on the other end (B and C) will not communicate with each other.
- Splitting an Ethernet cable multiple times using this strategy isn't possible (you can't separate the remaining two pairs again).
Rather than struggling with the many undesirable aspects of using Ethernet splitters, I would recommend going with the correct and ideal way to expand an Ethernet network.
The correct way to add additional clients to an Ethernet network is to use an Ethernet switch.
An Ethernet switch acts as a traffic controller on your network, forwarding packets to the desired recipients. Routers typically have a switch built into them, so those can work too.
Unmanaged Ethernet switches are plug and play, meaning that no configuration is required.
- The TL-SG108 is a well-known and reliable network switch.
- I own this exact switch model and have been using it without any problems for many years.
- It supports Ethernet speeds of up to 1 Gbps.
- Due to the fanless design, it is silent.
- It uses solid capacitors, which means that it should last a long time.
- It's an unmanaged switch, meaning that it's plug and play, and no configuration is required.
If you want to learn more about internet equipment, networking, wiring, or troubleshooting, check out these articles:
- Cat 5e vs. Cat 6a - Which to Buy?
- This article compares the various categories of Ethernet cables.
- How to Connect Ethernet Cables - Network Switches & Couplers
- This article explains how to use network switches and couplers for extending and distributing your network.
- Ultimate Cable Internet Wiring & Optimization Guide
- This guide shows you how to wire and optimize cable Internet for your home or office.
- Essential Equipment Guide for Cable Internet
- This guide shows you the essential components required for setting up your cable Internet connection.
- Ethernet Over Coax?! A Complete Guide to MoCA Adapters
- This guide discusses how to use existing coax cabling for distributing Ethernet and Wi-Fi throughout your house.
- Ultimate Cable Internet Troubleshooting Guide
- This guide shows you how to troubleshoot cable Internet problems.
- MoCA vs. Powerline? Which You Should Buy
- This article compares MoCA adapters and Powerline adapters for home networks.