This Recommendation specifies means to support Distribution Point Unit - Fast Backhaul (DPU-FB), which uses the G.fast technology for both the backhaul connections (back lines) and the connections to the G.fast NTs (front lines) in an environment where crosstalk cancelling between the wire-pairs of the back lines and wire-pairs of the front lines is required in addition to the FEXT cancellation provided by G.fast. This Recommendation is written as a delta Recommendation relative to [ITU-T G.9701]. For the clauses that have been changed, this Recommendation contains complete replacement text (unless explicitly indicated). For the clauses that have not been changed, this Recommendation contains only the clause heading, with reference to [ITU-T G.9701].