Good Sync Rate

Have just rebooted my HG612 - a rare occurrence!

On a 450m line, I have some pretty good stats:

Text

1 23 45 67 89 1011 1213 1415 1617 1819

xdslcmd info --stats xdslcmd: ADSL driver and PHY statusStatus: Showtime Retrain Reason: 0Last initialization procedure status:   0 Max:    Upstream rate = 23114 Kbps, Downstream rate = 80332 KbpsBearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 79999 Kbps Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 KbpsLink Power State:       L0 Mode:                   VDSL2 Annex BVDSL2 Profile:          Profile 17a TPS-TC:                 PTM Mode(0x0)Trellis:                U:ON /D:ON Line Status:            No DefectTraining Status:        Showtime                 Down            UpSNR (dB):        6.5             15.1 Attn(dB):        16.7            0.0Pwr(dBm):        13.6            7.0

And TBB speedtest is showing 74.6 Mbps - quite happy with that.

That's a pretty good stats as I can see SNR 6dB mean this is your final max line rate and who is your isp?

Edited by adslmax (Sun 23-Aug-15 22:06:34)

BT and the BT wholesale test gives a download rate at 77.5Mbps ...

I would say very good given the line length.

It's would be set at 77.35Mbps set by BT Openreach if it was G.INP enabled. Otherwise it will be set at 77.44Mbps if it was on fast path.

In reply to a post by MHC:

BT and the BT wholesale test gives a download rate at 77.5Mbps ...

I would say very good given the line length.

that BTW PT speedtest is wildly inaccurate i have had ds results in excess of the BTWi IP profile of 77.35 since moving to zen, but in reality throughput is lower around 74.5-75.2 mbps

Doesn't really fit in with the table on the website.

Fibre Broadband Guide

I was preparing myself for a 45Mbps connection when FTTC arrives, but you give me a lot of hope.

I expect you're one of the first people in your area to get FTTC and unfortunately I expect your sync speed will decrease due to crosstalk

Table assumes an almost worse case cross-talk scenario and thus follows the model of people being happy as they usually get better than the table suggests.

Ahh, that makes sense, thanks for explaining chaps.

It does seem a fair way out though - even at worst case.

This morning I am seeing 80768 kbps as the max attainable rate. The line is probably around 440-450m and I know the exact route within a metre or two of where it is underground. It is probably at the very top end of what can be achieved. Next time I have a BT Tech here I will get him to check the length using his TDR.

There was pressure for the figures to be even lower from some quarters, but settled on ANFP research worst case i.e. 70 to 80% take-up and no vectoring. Some fought for 350m to be absolute limit of superfast access and still do.

Same distance ranges are used for our coverage statistics, so that if anything we are under estimating superfast coverage.

Once vectoring goes national and a good sample of the changes it represents appear we will update, and info from some sub LLU doing vectoring is very promising.

It is creeping up even more! Now at 80984

In reply to a post by MHC:

This morning I am seeing 80768 kbps as the max attainable rate. The line is probably around 440-450m and I know the exact route within a metre or two of where it is underground. It is probably at the very top end of what can be achieved. Next time I have a BT Tech here I will get him to check the length using his TDR.

My last line had attenuation of 16.4dB, and acted very similarly to yours - though this was all before G.INP.

Back in 2012, the attainable speed only dropped from around 84/26 to 82/25, then stuck there for a long time. When we left, it was doing around 79/23.

That line was probably around 380-390m long.

In reply to a post by MrSaffron:

Some fought for 350m to be absolute limit of superfast access and still do.

Seriously? The limit of 24-30Mbps?

I know some pro-FTTP campaigners feel the need to belittle the actual capability of FTTC, but this is kinda ridiculous. Perhaps the "some" should be named and shamed!

In the meantime, Ofcom publish this as the speed distributions for UK FTTC:
http://postimg.org/image/bly6o16cl/

That suggests that only 10% of lines get sub-30Mbps speeds.

Meanwhile, the Sagentia report reckons D-side length distributions are:
http://postimg.org/image/bp372fcnn/

That suggests the longest 10% lines are >1km.

info from some sub LLU doing vectoring is very promising.

Oooohh .... do tell ... !

100 Mbps plus may be possible i.e. what we saw from the old Digital Region project previously

VDSL2 is far from perfect, but yes it delivering what makes the majority happy for now. Even where gigabit is available when people are given a choice of packages the 20 to 50 Mbps packages often win out, since many are happy to trade a bit of time for savings.

With the analysis we have done on line lengths from cabinets, the Sagenta stuff looks right.

Of course if one of those not getting decent speeds from VDSL2 one can understand the annoyance, i.e. those who've upgraded and still getting sub HD streaming speeds.

In reply to a post by WWWombat:

In reply to a post by MHC:

This morning I am seeing 80768 kbps as the max attainable rate. The line is probably around 440-450m and I know the exact route within a metre or two of where it is underground. It is probably at the very top end of what can be achieved. Next time I have a BT Tech here I will get him to check the length using his TDR.

My last line had attenuation of 16.4dB, and acted very similarly to yours - though this was all before G.INP.

Back in 2012, the attainable speed only dropped from around 84/26 to 82/25, then stuck there for a long time. When we left, it was doing around 79/23.

That line was probably around 380-390m long.

Peaked at 83Mbps earlier this afternoon. Attenuation is 16.7 ...

Is someone adding vectoring to your line, tone-by-tone?

I did wonder if Vectoring had been applied and it was going through a learning phase although I doubt it.

No, I doubt it too.

When I get improvements of that order, it usually happens suddenly - and I put it down to someone turning a modem off somewhere. The improvement usually disappears, perhaps a day later, perhaps a week or two.

I did a reboot as I could see quite a few tones that were locked out and my sync had slowly drifted down. A little surprised at the new level with max attainable over 80000 kbps and then the slow day by day increments.