Managing unvectored lines in a vectored group

Abstract

Vectoring technology allows removing far-end crosstalk from coordinated digital subscriber lines. Challenges arise when vectored lines are mixed with legacy VDSL2 lines in the same binder. Using data rate targets from the European Union's Digital Agenda, we show that an automated line management technique based on scalar parameters that control the maximum transmit power spectral density, signal-to-noise-ratio margin and data rate allows the vectored lines to recover part of the performance loss due to the presence of the legacy lines when the data rate on these legacy lines is significantly capped. This is a practical solution when all lines are served by a single operator. When multiple operators serve lines in the same access network, this technique does not provide a fair competition between the operators without loss of vectoring gains, and virtual unbundling may be preferred.