Modem
A modem is the box that turns your internet provider’s line, such as cable or DSL, into an Ethernet connection that a router can use.
What it means for you
The modem gets you online, and the router shares that connection with your devices and provides Wi-Fi. They can be two separate boxes or combined in one provider gateway, and fiber service uses a similar box called an ONT.
Guides on this topic
- Use Your Own Router With an Xfinity or AT&T Gateway
Add your own router or mesh behind an Xfinity or AT&T gateway without double NAT: Bridge Mode, IP Passthrough and what changes, from the providers' support pages.
- How to Choose a Wi-Fi Router
Match a router to your home size, internet plan and devices, with Wi-Fi 6, 6E and 7 explained.
- Why Does My Wi-Fi Keep Disconnecting?
Work out whether one device or the whole network is dropping, then follow the matching fixes.
Related terms
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Definitions are short and general. For model-specific details, check your device maker’s own documentation.