What Is DSL Internet? How Does DSL Internet Work, and How Fast Is It? (2024)

If you think about it, that makes sense: DSL is the OG of high-speed internet.

DSL has a lot going for it: it’s faster than dial-up; in a lot of cases it’s faster than satellite (and no latency for gamers); and it’s infrastructure makes it more available than either cable or fiber internet.

But how does DSL work exactly? What kind of speeds can you expect to get? What equipment will you need? And the most important questions of all: is DSL internet right for you and how do you get it if it is?

Let’s start by understanding how DSL internet works a little better.

Both DSL and old-school dial-up internet use phone lines to connect you to the internet; but dial-up works on a frequency that prevents you from being able to be on the (landline) phone and the internet simultaneously.

Plus, every time you use the internet with dial-up, you need to re-connect.

With that said, there are a lot of types of DSL service, but only 2 concern us: ADSL and VDSL.

ADSL – asymmetrical digital subscriber line – gives you more bandwidth for downloads than for uploads. This means that your download speed – all the data coming to your device – will be faster than your upload speed – any data going from your device to the internet.

By doing this, you’re able to get faster download speeds than if your bandwidth was symmetrical (equal upload and download speeds).

VDSL – Very high bit-rate digital subscriber line – is newer, and the fastest form of DSL available. It provides considerably faster speeds than ADSL.

When it comes to equipment, there isn’t much for you to do with DSL.

DSL Filter/Line splitter: As we touched on, this is a special filter that separates your phone line from your DSL. It allows you to use both simultaneously. It’s essentially an adapter that plugs into the phone jack in your wall.

If you have more than one landline phone, you’ll need to plug in a filter at every jack that’s connected to a phone so it doesn’t interfere. If you don’t have a landline at all, you just need one filter for your DSL connection to work.

DSL modem: You’ll receive a special modem from your internet service provider (ISP) that is specifically for DSL internet. A cable will run from your DSL filter to this modem.

Router: The router is what provides internet to your devices; if you want Wi-Fi, you’ll need a Wi-Fi router. Often, your ISP will provide this as well, usually for a monthly fee. You can also buy your own as long as it’s compatible with your provider. The DSL modem will connect to your router.

Landline phone jacks/wiring: Lastly, if your home isn’t wired for landline phones (it should be), you can’t use DSL internet until it is – it’s an essential part of the system.

Let’s clear something up quick: true DSL, while faster than dial-up by lightyears, is relatively slow – the fastest type (VDSL) caps out around 50Mbps or so.

However, most ISPs that offer DSL – often termed “broadband” – utilize as much technology as possible to boost that number up – which means their DSL offerings can reach as high as 100Mbps.

So with that said, DSL occupies the middle-ground for speed. You can check out the table above for a quick comparison of the internet type to DSL, or keep reading for the breakdown.

Satellite occupies the slower end of the spectrum for internet speed. In some areas, you may get speeds as fast as DSL; but in terms of reliably getting fast speeds – and being more affordable -, DSL wins out.

Plus, with satellite internet, latency is a far bigger concern – i.e. the time it takes between clicking on something online and the item responding. Check out our guide to satellite internet to learn more about that.

The only area where satellite reliably beats DSL is in availability: DSL is widespread, but satellite internet is available anywhere you can see the southern sky clearly.

The cable modem is different from a DSL modem, too – instead of running into your telephone line, a cable modem hooks up to a copper coaxial cable.

However, in some cases, DSL is more affordable; and in nearly every case, DSL is more widely available. That’s because DSL uses telephone wires, which are wider-spread than the underground cable lines that cable internet uses.

Plus, with cable internet, you share bandwidth with your neighbors; that means your internet will slow down when a lot of people are online at once.

Fiber-optic internet is the next-gen of cable internet: like cable, it runs underground, but unlike cable, it uses a different type of wiring that allows for much faster speeds – and symmetrical upload speeds, too.

Fiber is more expensive than DSL, and most providers offer 50-100Mbps for starting speeds. However, fiber-optic’s availability is super restricted in comparison to every other type of internet.

If you’ve decided that DSL is going to be the right option for you, how do you get it?

First, check out our guide to the best DSL internet providers. Then, dig into some individual reviews:

• CenturyLink Internet Review
• Frontier Internet Review

When you’re checking them out, compare on a few things: your budget, location, data caps, and hidden fees. Then, it’s time to call or order online.