Stands for "Digital Subscriber Line." It is medium for
transferring data over regular phone lines and can be used to
connect to the Internet. However, like a cable modem, a DSL
circuit is much faster than a regular phone connection, even
though the wires it uses are copper like a typical phone line.
An asymmetric DSL (ADSL) connection allows download speeds of up
to about 1.5 megabits (not megabytes) per second, and upload
speeds of 128 kilobits per second. That is why it is called ADSL
and not just DSL (because of the asymmetric speeds). There is
also a "Symmetric Digital Subscriber Line" (SDSL) which is
similar to ADSL, but allows data transfer speeds of 384 Kilobits
per second in both directions. Theoretically, this type of
connection allows download speeds of up to 9 megabits per second
and upload speeds of up to 640 kilobits per second. The
difficult part in establishing an DSL circuit is that it must be
configured to connect two specific locations, unlike a regular
phone line or cable modem. DSL is ofte