SLC_96 home-runs to avoid old quad telephone cables to maximize speed.
Quad in of itself was not a problem, what caused problems was how the quad was run, if it was hub and spoke that was easy to solve just install a inline splitter on every jack even it there was not a set connected there, the inline splitter would become a termination eliminating near end bridged tap reflections of the DSL signal.
However most prewired homes where wired in a ring, the IW would leave the NID loop around the prem to each jack and then end back at the NID.
That was a problem because if the DSL modem was not exactly in the middle of the loop it would receive the DSL signal from two different directions and due to the different loop lengths the two signals would arrive slightly out of phase causing peaks and nulls in the signal (multipath distortion) and because of that distortion the modem would take errors shutting down the errored bins, once enough bins where shut down speed would drop and remain low until the modem was power down reset, which place all the bins back into service, until more errors where collected..
That was one of the primary reasons TS would have the sub do a power down reset which allowed the remote test to come back good so the ticket could be closed.
Of course that didn't solve the problem so sooner or later the sub would blow up on TS and a truck roll would be initiated.
The easy fix for the tech as I explained to a number of them was to open the jack where the modem was plugged in and split the loop allowing the modem to be fed from a single direction from the NID, or if the tech really wanted to solve the problem after splitting the quad install a whole home splitter at the NID and feed the modem on the yellow/black, which how the Alcatel 1000 was designed to be connected.
Doing that totally isolated the POTS from the DSL signal feeding the MODEM and the problem was solved properly.
