The five jobs of a home router
A home “router” is really several devices in one box:
| Job | What it does |
|---|---|
| Routing | Sends each packet to the right place: to a device at home, or out to the internet. |
| NAT | Lets all your devices share the one public IP address your ISP gives you. |
| DHCP | Gives each device a private address like 192.168.1.23 when it joins. |
| Firewall | Blocks connections from the internet that your devices didn't start. |
| Wi-Fi access point and switch | Connects devices wirelessly and through the Ethernet ports on the back. |
Router, modem or both?
The modem (or fibre ONT) connects to your ISP's line; the router builds your home network on top of it. Many ISPs supply a single box that does both. If you have two boxes, the one connected to the wall is the modem/ONT and the one making Wi-Fi is the router. Modem vs router explains how to tell them apart.
Lights and ports
Labels vary by brand, but most routers show the same things:
- Power: on steadily when running.
- Internet / WAN (or PON/LOS on fibre units): shows the connection to the ISP. Red or off usually means an ISP-side or line problem.
- Wi-Fi (2.4G / 5G): on or blinking when the wireless networks are active.
- LAN 1–4: lit when a cable device is connected.
- WAN port: often a different colour; this is where the cable from the modem/ONT goes.
What you can change in the router settings
The admin page, usually at an address like 192.168.1.1, lets you change the Wi-Fi name and password, see connected devices, set parental controls, forward ports, change DNS servers and update firmware. See router login for how to get in safely.
When a router is the bottleneck
Signs include Wi-Fi speeds far below your plan even close to the router, frequent drops that a restart fixes, and the whole network slowing when one device downloads. Test on a cable and on Wi-Fi next to the router with our speed test. If the cable gets full speed but Wi-Fi next to the router doesn't, the router's Wi-Fi is the limit (Wi-Fi standards).
Common questions
Do I need a router if I have a modem?
If you want more than one device online, yes. A plain modem gives one connection; the router shares it and provides Wi-Fi. Most ISP-supplied boxes are both in one.
How long does a router last?
The hardware often works for many years, but security updates stop sooner. Replace a router when the manufacturer no longer releases firmware for it, or when it can't deliver your plan's speed over Wi-Fi.
Does restarting the router help?
Often. A restart clears memory leaks and stuck connections and can pick a less congested Wi-Fi channel. If you need to restart it frequently, update the firmware or replace it.