Editing VDSL (section)

== Conceptual development ==
The concept of VDSL was first published in 1991 through a joint [[Bellcore]]-[[Stanford]] research study. The study searched for potential successors to the then-prevalent [[HDSL]] and relatively new [[ADSL]], which were both 1.5&nbsp;Mbit/s. Specifically, it explored the feasibility of symmetric and asymmetric data rates exceeding 10&nbsp;Mbit/s on short phone lines.

VDSL2 standard is an enhancement to ITU T G.993.1 that supports asymmetric and symmetric transmission at a bidirectional net data rate up to 400&nbsp;Mbit/s on twisted pairs using a bandwidth up to 35&nbsp;MHz.