DSL is digital subscriber line. DSL offers much faster speeds than does dial-up. However, it uses the traditional twisted-pair copper wires. For most residential customers, speeds of about 500 kbps (or 10 times that of dial-up) are available. DSL could offer up to 7 Mbps, using today's technologies.

Typically, DSL means "ADSL," or asymmetric DSL, which offers much higher speeds in one direction than in the other. Symmetric DSL (SDSL), which provides high speeds in both directions, is more expensive than is ADSL and is less widely available. ADSL2 and ADSL2+ can reach, respectively 12 Mbps and 25 Mbps. Very high data rate DSL (VDSL), modems can achieve speeds up to 106 Mbps downstream (to you) and 43 Mbps upstream (from you), according to Light Reading Insider (9/8/04). The key with VDSL, ADSL2 and ADSL2+ is that they can bring much faster broadband to end users through standard twisted-pair copper wires and do so without costing providers huge infrastructure enhancement outlays.

The most common form of DSL in the US today is ADSL, which is limited to about 2.5 miles distance from a telephone company hub station with a DSLAM connection. This is unfortunate for people in rural areas, because the phone company often uses far fewer hub stations in rural areas than in suburban or urban areas. This is because each hub station supports a certain number of telephone customers, and rural areas are often run as distant branches from suburban areas, to reduce the telephone company's overhead. In summary, most rural customers, unless they are extremely lucky, cannot get DSL service.