Modems, routers & WiFi
Network switch vs router: how do you add more ethernet ports?
A router shares your internet connection and runs the home network. A network switch only adds ethernet ports to it. To get more ports at the TV cabinet or the office from one cable, plug a small unmanaged switch into the socket there. It always goes after the router, never between the router and the NBN box.
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The TV cabinet has a smart TV, a games console and a streaming box, and there is one ethernet port in the wall. Or the office has one data point and a desktop, a printer and a docking station that all want a cable. You do not need another cable run for each of them: in most homes, a small box called a network switch turns one port into four or eight. If there is no cable at the cabinet or the desk yet, that part is data cabling to the TV cabinet or the office; if there is, this post covers the rest.
What is the difference between a network switch and a router?
A router connects your home to the internet and runs the home network; a switch only adds more ports to that network. Cisco puts it simply: a switch connects the devices on one network to each other, and a router connects networks, including yours to the internet.
Your router does the jobs that make the internet work in the house. It shares the one connection from the NBN, hands every device its address, makes the WiFi and keeps the firewall. A switch does none of those. It takes one cable in and gives you more ports out, and every device plugged into it gets its address from the router, exactly as if it were plugged into the router itself.
Our technician’s way of putting it on the phone is that the router is the brain, and a house only ever wants one. The four yellow ports on the back of your modem are already a small switch, built into the router. A separate switch is the same thing in its own box, put where the ports are needed. For the router’s side of it, and which box on your NBN is really the modem, see the difference between a modem and a router.
How do you add ethernet ports at the TV cabinet from one cable?
Plug a small switch into the wall socket at the cabinet, then plug the TV, the console and the streaming box into the switch. The one cable from the router to that socket now serves all of them.
You cannot split a data cable to get a second port, the way a double adapter splits a power point. Each socket in the wall has its own cable, and the way to get more ports out of one cable is a switch.
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Check the wall socket is live
Plug a laptop into the socket with a lead and run a speed test. If it gets the same speed as plugged straight into the router, the cable is good. If it gets nothing, the socket or the cable behind it needs looking at before a switch will help.
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Get a small unmanaged gigabit switch
Pick one with more ports than you need today, because a cabinet always gains another box. It needs a power point nearby for its plug pack.
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Connect the switch to the wall
A patch lead from the wall socket into one of the switch's ports. Its lights come on as soon as it sees the router at the other end of the cable.
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Plug the devices into the switch
One lead from the switch to each device. There is nothing to set up: each device gets its address from the router as if it were plugged in beside it.
- Connected
- Not connected
- Drops off
One port, one device
One cable, one socket, one device. The console and the streaming box have nowhere to plug in.
A switch at the cabinet
A small switch on the socket turns one cable into four ports. Every device gets its address from the router, as if it were plugged in beside it.
Switch on the NBN box
The NBN box hands over one connection for one router. A switch in front of the router cannot share it. The router goes first, the switch after.
A second router
An old router behind the new one is a second brain handing out addresses. Devices drop off. Use a switch, or set the old router to access point mode.
One cable is usually plenty for a TV cabinet. Everything coming from the internet already shares one connection, your NBN plan, so a gigabit cable to the cabinet only becomes the limit on a plan faster than a gigabit. A TV, a console and a streaming box sharing it will not notice.
The office is where a second cable earns its place: two people on video calls, a desktop copying large files to a drive elsewhere in the house, or an access point on the same run. If every device on the end of one cable is moving a lot of data at once, one cable will not cut it. And if the wall is being opened anyway, our technician’s advice is to pull two cables rather than one, because the second takes the same time to run.
Where does a network switch go?
After the router, wherever the ports are needed. That is either at the far end of one cable, at the TV cabinet or the desk, or at the hub beside the router, where it fans the house’s cables out to each room.
- At the far end of a cable. The TV cabinet, the desk, a games room. One cable in, the devices out.
- At the hub, beside the router. Once a house has more data points than the router has ports, a switch beside the router connects them all. It is sized to the points: a dozen ports for ten points, more for a bigger house, with a patch panel once there are more than a handful of cables.
- With the NBN box in the garage. Either the router and the switch stay in the garage and every point runs from there, or one cable takes the internet to the middle of the house and the router and switch go there. NBN box in the garage weighs up the two.
- Somewhere you can reach. A switch needs power and air, and you need to be able to see its lights and restart it. A sealed cupboard or a ceiling space nobody can get into is a poor home for one.
If the house has no cables back to a hub yet, Cat5e vs Cat6 vs Cat6a covers the cable that goes in, and why the way it is finished matters more than the label.
Unmanaged, managed or PoE: which switch do you need?
For a home, an unmanaged switch: it works the moment it is plugged in, with nothing to set up. A managed switch is for a network someone administers, and a PoE switch is for when the devices on the end of the cables need their power through it, such as cameras and ceiling access points.
| Kind | What it does | Where it fits | Setting up |
|---|---|---|---|
| Unmanaged | Adds ports and passes everything through | The TV cabinet, the desk, the hub in most homes | None. Plug it in |
| Managed | Can be configured for security, traffic and capacity | Offices and larger networks someone looks after | Needs setting up by whoever runs the network |
| PoE | Sends power and data down the same cable | IP cameras, ceiling access points, IP phones | Match the device's PoE type to the switch |
Cisco’s guide to switches (opens in a new tab) describes unmanaged switches as plug and play, suited to small networks, and managed ones as switches a networking expert configures, with more capacity, flexibility and control. Configuring a managed switch is IT work rather than cabling, so if an office has one, whoever looks after the network’s settings is the person for it.
What is a PoE switch?
A PoE switch sends power down the network cable as well as data, so a camera on the eaves or an access point on the ceiling needs no power point of its own. TP-Link’s page on PoE (opens in a new tab) lists IP cameras, wireless access points and IP phones as the usual devices, and sets out the three types by the power each port can supply: 15.4 watts, 30 watts, and 60 or 90 watts. Check the device’s type against the switch before you buy. Power and data both reach the normal 100 metres of cable.
Where there is no PoE switch, a PoE injector does the same for one device: it sits in line between an ordinary switch port and the device, and plugs into a power point. That is how the outdoor dishes of a wireless bridge are usually powered. On the job on our WiFi technician page, the power an access point was drawing down a long cable had dropped too far by the time it arrived, and a powered switch fixed it.
PoE is not powerline. People on the phone often call powerline adapters, which send the network through the power wiring, “power over ethernet”, but they are a different thing. Powerline adapters vs mesh WiFi vs a cable covers those.
These are the switches that fit each case, from a five-port box behind the TV to PoE for cameras and 2.5 gigabit for the fastest plans.
We earn a small commission if you buy through our Amazon links, at no extra cost to you. As an Amazon Associate we earn from qualifying purchases.
| Product | What it is for | Link |
|---|---|---|
| TP-Link TL-SG105 | 5 ports, plug in and go | View on Amazon for the TP-Link TL-SG105 (opens in a new tab) |
| TP-Link TL-SG108 | 8 ports, plug in and go | View on Amazon for the TP-Link TL-SG108 (opens in a new tab) |
| NETGEAR GS308 | 8 ports, silent | View on Amazon for the NETGEAR GS308 (opens in a new tab) |
| TP-Link TL-SG108E | 8 ports, VLANs and QoS | View on Amazon for the TP-Link TL-SG108E (opens in a new tab) |
| TP-Link LS105GP | 5 ports, PoE on four | View on Amazon for the TP-Link LS105GP (opens in a new tab) |
| TP-Link TL-SG108PE | 8 ports, PoE on four, managed | View on Amazon for the TP-Link TL-SG108PE (opens in a new tab) |
| TP-Link TL-SG108-M2 | 8 ports at 2.5 gigabit | View on Amazon for the TP-Link TL-SG108-M2 (opens in a new tab) |
What should you not do with a network switch?
Three mistakes cause most of the switch trouble we hear about: plugging it into the NBN box instead of the router, making a loop, and adding an old router where a switch was needed.
Don’t plug the switch into the NBN box
On fibre to the premises, HFC and fibre to the curb, the NBN box hands over one connection, and the router is what shares it. NBN’s installation guidelines for the fibre box say your WiFi router is what connects to it. A switch between the box and the router cannot share that connection, so the order is always the NBN box, then the router, then the switch.
The other ports on a fibre NBN box are not spare switch ports either. Each one is a separate service, and only the ones a provider has switched on do anything. On fibre to the node and fibre to the building there is no separate NBN box: the modem is the router, and the switch goes into one of its yellow ports.
Don’t make a loop
A loop is two paths between the same two points on a network, and it can bring the whole network down. NETGEAR’s knowledge base (opens in a new tab) describes the result: the traffic goes round and round and multiplies, the internet goes slow and irregular or stops, and the name for it is a broadcast storm.
- Both ends of one lead in the same switch. It happens when a cable is tidied up and pushed into the nearest empty port. Unplug it.
- Two cables between the same two boxes. Two runs from the router to the same switch, or two switches joined twice. Use one.
- A device on cable and WiFi to the same network. NETGEAR’s example is a device connected to a router or extender by both WiFi and ethernet. Unplug the cable or turn that device’s WiFi off.
Don’t add an old router to get more ports
An old router plugged in behind the new one is a second brain on the network. Plugged in by a yellow port, it hands out addresses alongside the new one, which our technician calls IP conflicts; plugged in by its internet port, it builds a second network inside the first, which the makers call double NAT. Either way, devices drop off or will not connect. If you want to reuse an old router for its ports, NETGEAR’s advice on fixing double NAT (opens in a new tab) is to set one box to access point or bridge mode, so only one runs the network. A switch avoids the problem altogether.
Why does a device on the switch drop out or run slow?
Take the switch out of the chain and test again. Plug the device, or a laptop, straight into the router with a cable: if the problem goes away, it is the switch, the lead or the cable to the switch; if it stays, it is the device or the connection.
- Swap the lead and the port. Try a different patch lead and a different port on the switch. A cable has only two ends, so it is either the leads, the cable, the port or the device.
- Restart the switch. Unplug its power, wait a moment and plug it back in. A switch that restarts on its own every so often will drop everything on it each time.
- Check it is gigabit. An old switch with 100 megabit ports caps every device on it at 100, whatever the plan.
- Restart the device. A printer or a camera that has lost its address often picks up a new one from the router after a restart.
If the device is slow even plugged straight into the router, the switch is not the problem, and an internet technician who tests the connection is the next step.
When you need a technician, and when you don’t
You do not need a technician to buy a switch, plug it in or move devices onto it: that is yours to do, and it takes minutes. If you would rather someone set up the router, the WiFi and the devices on it, that is home tech support, not cabling.
You do need us when there is no cable where the switch would go, when the wall socket at the cabinet does not work, or when the house needs points in several rooms run back to a switch at the hub. That is data cabling, and it is quoted. The data cabling cost estimator asks whether you want a switch or access points from us and gives a price range in about two minutes, and how many data points a home needs helps you decide how many runs to ask for. For ceiling access points on their own cables, a WiFi technician who plans where they go is the better fit.
Frequently asked questions
Is a network switch the same as a router?
No. A router connects your home to the internet: it shares the connection, gives each device its address, makes the WiFi and runs the firewall. A network switch only adds more ethernet ports to the network the router has made. Devices plugged into a switch get everything from the router, just as if they were plugged straight into it.
Can I plug a network switch into my NBN box?
Not in place of the router. The NBN box hands over one connection for one router, and the router is what shares it with the house. Plug the router into the NBN box, then plug the switch into one of the router's ports or into a wall socket fed from it. The other ports on a fibre NBN box are separate services, not spare switch ports.
Do I need a managed or unmanaged switch at home?
Unmanaged, in nearly every home. It works as soon as it is plugged in and has nothing to set up. A managed switch can be configured for security and traffic control, which suits offices and networks someone looks after. If the devices on the end need their power through the cable, such as cameras or ceiling access points, you want a PoE switch.
Does a network switch slow down the internet?
Not a gigabit switch in good order. Everything coming from the internet already shares your one NBN connection, so the cable to the switch only becomes the limit on a plan faster than a gigabit, or when devices on it copy big files to each other. A switch that keeps restarting, or a tired lead, can cause dropouts, so test with the device plugged straight into the router.
Need this fixed rather than explained?
This is written from the field. When the fault needs a technician on site, this is where to go next.