TAZ posted : No, this is an obvious case of a line problem (unknown if inside or outside) or hardware problem (less likely, but still a possibility).
VDSL2 upstream is far more distance-limited than downstream because most of the upstream spectrum is in the higher frequencies. (Useful reference: »www.joepeesoft.com/Publi ··· SL2.html) Your loop is short enough to train at 18M upstream even in these conditions. Something appears to be knocking out a significant portion of DS spectrum and likely some US spectrum as well, thus your 10/18 train rate while at or close to 6 dB.
In other words: because upstream is the limiting factor, if your loop is capable of 18M upstream, it should also be capable of 50M downstream and higher (once the problem is resolved). And unless this problem is magically affecting only DS spectrum and not touching US in the slightest, I'd expect 20M US once this is resolved.
billaustin![See Profile]()
's recommendation is sound and should be the first thing you do. (And there's a pretty good chance that will resolve the problem.) If you have a spare VDSL2 modem, you can also try that, but otherwise if you have no luck at the NID, call for a tech (and hopefully you'll get a competent one unlike the fool who supposedly noted the loop was too long).
FWIW also, "not getting the full speed on [presumably properly functioning] DSL lines" mostly refers to ATM-based circuits (ADSL). Once this is resolved, CL should eventually overprovision you to 50/20 so you'll actually be getting more than the advertised speed on the DS side.
VDSL2 upstream is far more distance-limited than downstream because most of the upstream spectrum is in the higher frequencies. (Useful reference: »www.joepeesoft.com/Publi ··· SL2.html) Your loop is short enough to train at 18M upstream even in these conditions. Something appears to be knocking out a significant portion of DS spectrum and likely some US spectrum as well, thus your 10/18 train rate while at or close to 6 dB.
In other words: because upstream is the limiting factor, if your loop is capable of 18M upstream, it should also be capable of 50M downstream and higher (once the problem is resolved). And unless this problem is magically affecting only DS spectrum and not touching US in the slightest, I'd expect 20M US once this is resolved.
billaustin
's recommendation is sound and should be the first thing you do. (And there's a pretty good chance that will resolve the problem.) If you have a spare VDSL2 modem, you can also try that, but otherwise if you have no luck at the NID, call for a tech (and hopefully you'll get a competent one unlike the fool who supposedly noted the loop was too long).FWIW also, "not getting the full speed on [presumably properly functioning] DSL lines" mostly refers to ATM-based circuits (ADSL). Once this is resolved, CL should eventually overprovision you to 50/20 so you'll actually be getting more than the advertised speed on the DS side.