For my connection, the drop wire comes from the DP at the top of the pole across the road from my house to another pole on my side of the road & then straight into the master socket.
When FTTC was first installed the drop wire came in upstairs at the front of the house.
The installing engineer re-used my existing high speed braided data extension cable to reposition the master socket downstairs, near my P.C.
He then used a spare pair in the braided cable to back-wire to what was the original master socket upstairs, making it an extension.
A number of other phone extensions run from that socket, some plugged in & one hard wired in a daisy chain sort of configuration.
It all worked perfectly for around a month, giving me 33 Mb steady throughput download speeds (which must have meant a sync speed of around 35Mb on the original 8c profile - I didn't have access to any modem stats back then, June 2011).
Come near the end of July, my telephone & FTTC services were completely cut off for 4 days. I believe it was some sort of earth fault somewhere external to my house, but I have no idea exactly where.
My wife who was at home at the time the engineers visited told me it took at least 3 of them them a few hours to restore services.
Ever since then, my connection has been rather unstable (almost unuseable at times) with sync speeds as low as 7Mb or 8Mb.
Back in November, the drop wire was replaced from the DP at the top of the 2nd pole & rerouted to make the downstairs socket at the rear of the house a true master socket (the whole socket was also replaced), again re-using my braided cable to make upstairs the first extension socket.
I have tried a few 2 week periods of running the connection with everything else disconnected by removing the faceplate, both from when the drop wire came in upstairs at the front & more recently since it came directly in directly to the downstairs master socket.
I could cope with occasional slow throughput at congested periods.
However, I don't really see any congestion on my connection, usually achieving throughput of around 97% of IP Profile (regardless of the time of day), IP Profile usually being 96.79% of sync speed.
I suspect that an intermittent D-side HR fault was introduced at the time my 4 day loss of service was restored.
An engineer once used a 'Hawk' to run a TDR test on my connection from the end of the drop wire (when it came in upstairs at the front of the house), stating that he had found "something" near the cabinet.
On his return from his trip to the cabinet, he said he had found that someone had "absolutely stupidly" double-jumpered my connection, actually inside the cabinet, which must have been the cause of my connection's problems.
This engineer would not run another TDR test to confirm he had located & fixed the one & only fault as he said "it wasn't necessary".
Unfortunately, the removal of the double-jumpering appeared to have no lasting effect whatsoever on the performance & stability of my connection.
That was back in August 2011.
Despite being requested (by me), not one of the other visiting engineers have been prepared/willing to run a TDR test on my connection
I have tried to purchase a 'Mole' 301C tester on Ebay a few times, just so that I could run a TDR test myself, but was outbid in the closing seconds each time.
I have never achieved much in the way of bit-loading in the D2 frequency band & have never achieved anything at all from the higher D3 frequency band.
However, today I see that my Line & Signal attenuation have increase a little & I am achieving nothing at all from the D2 band:-
# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY statusStatus: Showtime
Retrain Reason: 2Max: Upstream rate = 6015 Kbps, Downstream rate = 29240 Kbps
Path: 0, Upstream rate = 6004 Kbps, Downstream rate = 21172 Kbps
Discovery Phase (Initial) Band PlanUS: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939) Medley Phase (Final) Band Plan
US: (0,95) (868,1207) DS: (32,859)
VDSL Port Details Upstream DownstreamAttainable Net Data Rate: 6015 kbps 29240 kbps
Actual Aggregate Tx Power: 6.3 dBm 10.9 dBm============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3 Line Attenuation(dB): 8.4 54.0 64.0 N/A 22.1 64.1 0.1
Signal Attenuation(dB): 10.7 53.3 N/A N/A 22.1 N/A N/A SNR Margin(dB): 6.0 6.1 N/A N/A 10.3 N/A N/A
TX Power(dBm): -4.1 5.8 N/A N/A 10.9 N/A N/A
Along with US attenuation looking rather high in comparison with other users' stats, fluctuating SNRM levels when the phone is used, fluctuating power levels most of the time (unlike other users' "straight line" power levels, regular re-syncs & low speeds, what else can I do to provide evidence that there is a physical fault - probably intermittent - somewhere between my home & the cabinet (or even inside the cabinet itself) to get this fixed once & for all?
My connection is probably only 800m or so in length.