What is DSL?

Digital Subscriber Line (DSL) is the most common broadband connection in homes today. DSL connects you to the internet through a dedicated pair of copper wires within your telephone lines and the use of a modem. Because DSL transmits at a different frequency than your voice service, it doesn’t interfere with home phone service, allowing you to be on your phone and internet at the same time.  

Types of DSL

There are a number of different types of DSL service, all described below. CenturyLink provides broadband services over ADSL, ADSL2+, VDSL2 and G.fast technologies, varying by geographic location.

Asymmetrical Digital Subscriber Line (ADSL)

ADSL is called asymmetrical because it provides faster download speeds than upload. Dowload speeds can be up to 8 Mbps, and upload speeds are 800 Kbps.


ADSL2+ is a newer version of ADSL that connects at higher frequencies, which increases both download and upload speeds. ADSL 2+ can provide download speeds of up to 24 Mbps and upload speeds of up to 1.4 Mbps.

Very-high-speed Digital Subscriber Line (VDSL)

This type of DSL connection (also sometimes known as Very-high-bit-rate) connects at even higher frequencies than ADSL 2+, providing download speeds of up to 52 Mbps and upload speeds of up to 16 Mbps.


VDSL2 uses the highest frequencies of any of the DSL connections and can provide speeds of up to 100 Mbps for both download and upload.

G.fast access to subscriber terminals

This technology can connect new fiber lines to existing copper lines over the last 500 feet or less of transmission. This enhancement to DSL service can provide speeds up to 940 Mbps. It’s currently available in limited locations.

Pair bonding

Pair bonding is an option for some DSL connections that generally provides double the bandwidth as compared to single line DSL service. With typical DSL service, there is only one pair of copper wires being used to deliver internet service. With pair bonding, two copper wire pairs (four wires) are used, thereby doubling your internet speed.  When using pair bonding, speeds can reach up to 200 Mbps.  Pair bonding services are subject to availability within CenturyLink’s internet coverage.

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Now that you understand DSL, click the button below to see what service is available in your area and get connected today.

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