Vectoring is a transmission method that employs the coordination of line signals for reduction of crosstalk levels and improvement of performance. It is based on the concept of noise cancellation, much like noise-cancelling headphones. From 2010 ITU-T G.993.5, Self-FEXT cancellation (vectoring) for use with VDSL2 transceivers, describes vectoring for VDSL2. The scope of Recommendation ITU-T G.993.5 is specifically limited to the self-FEXT (far-end crosstalk) cancellation in the downstream and upstream directions. FEXT generated by a group of near-end transceivers and interfering with the far-end transceivers of that same group is cancelled. This cancellation takes place between VDSL2 transceivers, not necessarily of the same profile.
Although technically feasible at the moment vectoring is incompatible with local-loop unbundling but future standard amendments could bring a solution.
Read more about this topic: Very High Speed Digital Subscriber Line 2