What Is a DSL Modem?

Learn about one of your several internet options

A DSL modem is a piece of hardware that brings a data signal into your home. You'll usually receive one from your internet service provider when you set up your account. While all modems provide similar functions—transmitting online information back and forth—a DSL modem is unique to a specific kind of signal.

An Ethernet bridge with an open DSL port

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What Does DSL Mean?

DSL is short for "digital subscriber line." This type of data connection uses phone lines to send and receive information. You'll usually buy the service from a phone company specializing in non-cellular options (i.e., landlines).

A DSL signal uses a higher frequency than a regular phone line so that you can use both services simultaneously. If you're using a landline and DSL, you'll usually need to add an adapter to split the port and plug both your phone and modem in at the same time.

What's the Difference Between a DSL Modem and a Router?

You'll need a DSL modem to use the internet; it's the connection that handles the data traffic entering and leaving your home or office. A router is optional, however. You'll use it to set up a wireless network and use your devices without connecting them directly to the modem.

While you'll always have a modem to connect to the internet, you may or may not use a router, depending on your needs. DSL is not the same as Wi-Fi because the former describes the actual internet connection, and the latter refers to how information from that connection moves through your home or building.

You can often get a combination modem and router from your ISP, which combines both functions in a single box. Alternatively, you can buy one from your preferred electronics store.

How Fast Is DSL?

Because DSL is an older technology, it won't usually hit the same upload and download speeds as newer offerings like cable and fiber internet. Depending on availability in your area, you can get up to 100 Mbps, which is more than enough to stream the highest quality content from platforms like Netflix.

  • How do I set up my DSL modem?

    To set up your modem, plug it into the cable or phone outlet on your wall, then connect your modem to a router to set up a Wi-Fi network.

  • How do I reset my DSL modem?

    Press the Reset button on the back or side of the device. Restarting or resetting your modem can fix a lot of connection issues.

  • Why is my DSL modem not working?

    Reasons your modem isn't working could include loose power or coax connections, damaged Ethernet cable connections, miscommunication with the router, overheating, or outdated firmware.

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