Kitz Forum
Broadband Related => Broadband Technology => Topic started by: adslmax on January 31, 2020, 12:52:56 AM
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Are these figure correct between VDSL2 and G.fast?
Mine is according to google map (dsl cable route to the pcp cabinet from back garden to the cabinet - not straight line)
831 ft - 253.1 metres line length - VDSL2 (this the same reported as GEA Test Estimated Line Length In Metres: 253.1
929 ft - 283.1 metres line length - G.fast
or
732 ft - 223.1 metres line length - G.fast
How does signal attenuation relate to wire gauge and distance ?
Attenuation relates to wire gauge and distance (approximately) as follows:
wire gauge thickness @300kHz @68kHz
22 AWG .64 mm 8.62 4.62 db/km
24 AWG .51 mm 11.90 6.65 dB/km
26 AWG .40 mm 13.81 9.37 dB/km
A sensible formula, in common use, assuming 26AWG wire, is:
DS_Atn = 13.81 dB/km * distance
It is important to note that long loop wire thickness is not consistent, it tends to increase with distance from the CO. Thinner twisted pairs are often used underground near the CO while thicker wires are used on long loops in the regions closer to the subscriber location in order to minimize the total loop resistance.
Because most loops are made up of different gauges of wire the Atn/km ratio can decrease (stepwise) with distance and is not a linear function of the loop length.
https://www.speedguide.net/dsl_speed_calc.php
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I have no idea what you're actually asking?
It doesn't matter. The numbers from the modem in terms of maximum achievable rate matter, not a theoretical calculator that takes no account of actual conditions or indeed the attenuation it reports as how this is arrived at varies.
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^This
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Are these figure correct between VDSL2 and G.fast?
Mine is according to google map (dsl cable route to the pcp cabinet from back garden to the cabinet - not straight line)
831 ft - 253.1 metres line length - VDSL2 (this the same reported as GEA Test Estimated Line Length In Metres: 253.1
929 ft - 283.1 metres line length - G.fast
or
732 ft - 223.1 metres line length - G.fast
I'm stopping at this point and will offer a comment on the above. We know the infrastructure layout for both a VDSL2 and a G.Fast circuit.
For the former, it is a metallic pathway of length X metres (the NTE5 to the PCP) and tie-cable length of Y metres (linking the PCP to the DSLAM in a separate cabinet). If I were to attach a time domain spectrometer to the pair at the NTE5 I could easily see the low-pass filter in the "fibre cabinet", which would be a distance (essentially) equal to X + Y metres. (The 253.1 metres you mention, above.)
For the latter, it is the same metallic pathway of length X metres (the NTE5 to the PCP) and an additional length of Z metres (linking the PCP to the DSLAM in the PCP's side-pod). The length of Z metres will be less than Y metres (from the VDSL2 case). Again, if I were to attach a time domain spectrometer to the pair at the NTE5 I could easily see the low-pass filter in the PCP's side-pod, which would be a distance (essentially) equal to X + Z metres.
As (Y > Z), then (X + Y) > (X + Z). Hence looking at the distances you mention, above, I suggest that out of the two the 223.1 metres would be correct.
Finally I am going to drop the decimal point ones from both values and say, from what you have shown, your VDSL2 circuit length was 253 metres and your G.Fast circuit length is 223 metres.
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Thanks burakkucat
VDSL2 80/20 about right for 253.1m (max rate 90/26)
G.fast 229/50 about right for 223.1m (max rate 249/52)
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You are welcome. But please do not obsess over those values.
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Look like ISPreview are spot on
Distance to cabinet (metres) Estimated downstream speed Estimated upstream speed Cumulative %’age of premises at this distance
100m 500 Mbps 50 Mbps 11%
150m 300 Mbps 45 Mbps 20%
200m 250 Mbps 40 Mbps 31%
300m 150 Mbps 20 Mbps 52%
370m 100 Mbps 20 Mbps 64%
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300m 150 Mbps 20 Mbps 52%
370m 100 Mbps 20 Mbps 64%
I think I'd cry if I knew what the stats are for 2,000m !
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I think I'd cry if I knew what the stats are for 2,000m !
0 Mbps. Now you know.
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I think I'd cry if I knew what the stats are for 2,000m !
My 450m line wouldn't even sync.... so technically no stats to even be had!
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Thanks burakkucat
VDSL2 80/20 about right for 253.1m (max rate 90/26)
G.fast 229/50 about right for 223.1m (max rate 249/52)
;D
Well this figures proved me wrong above!
VDSL2 80/20 about right for 243.6m (max rate 88/27)
G.Fast 221/29 about right for 213.6m (max rate 224/30)
DSLAM type / SW version: BDCM:0xc190 (193.144) / v0xc190
Modem/router firmware: AnnexA version - A2pvfbH045o.d27j
DSL mode: G
Status: Showtime
Uptime: 7 days 21 hours 29 min 36 sec
Resyncs: 0 (since 15 Jun 2021 17:18:49)
Downstream Upstream
Line attenuation (dB): 39.1 0.0
Signal attenuation (dB): 39.1 0.0
Connection speed (kbps): 221685 29359
SNR margin (dB): 3.1 3.1
Power (dBm): 0.0 4.0
Interleave depth:
INP: 550.00 538.00
G.INP: Not enabled Not enabled
Vectoring status: Not monitored
RSCorr/RS (%): 0.1696 0.2134
RSUnCorr/RS (%): 0.0000 0.0000
ES/hour: 0 0
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Does those relatively tiny differences matter ?
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Does those relatively tiny differences matter ?
Not in the grand scheme of things, we could be looking at cable quality making an iota of difference, but it doesn't really matter as @adslmax is paying for 160/30 and getting exactly what they are paying for.
It's like a car being capable of more than 70mph but means nothing as that's the national speed limit.
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Exactly well said. However I think @adslmax has regraded so will fret over the speeds.
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Exactly well said. However I think @adslmax has regraded so will fret over the speeds.
I'm not sure adslmax has, here's a quick NGA (next generation access) GEA (generic ethernet access) test on a Talk Talk Business Standard 330M G.fast product.
Sync Status In Sync
Downstream Speed (MBPS) 204
Upstream Speed (MBPS) 46.4
Estimated Line Length In Metres 199.2
adslmax's upload looks to be banded at 30...
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I'm not sure adslmax has, here's a quick NGA (next generation access) GEA (generic ethernet access) test on a Talk Talk Business Standard 330M G.fast product.
Sync Status In Sync
Downstream Speed (MBPS) 204
Upstream Speed (MBPS) 46.4
Estimated Line Length In Metres 199.2
adslmax's upload looks to be banded at 30...
What does your stats line attenunation say? If your is 35.4dB then you have a better upstream at 46.4 rather than my line attenuation 39.1dB is 30.0 for upstream.
The ISP won't given me GEA TEST say it not available for G.fast only for FTTC
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🤦♂️
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VDSL2 80/20 about right for 253.1m (max rate 90/26)
G.fast 229/50 about right for 223.1m (max rate 249/52)
Well this figures proved me wrong above!
VDSL2 80/20 about right for 243.6m (max rate 88/27)
G.Fast 221/29 about right for 213.6m (max rate 224/30)
Max, please remember those values are just estimations and nothing more.
The one decimal place is really irrelevant so we are looking at --
January 31,2020: VDSL2 253 metres, G.Fast 223 metres
June 15, 2021: VDSL2 244 metres, G.Fast 214 metres
Difference: 9 metres, 9 metres
As far as I am concerned, +/- 9 metres is well within the experimental error for crude estimations such as the above.
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What does your stats line attenunation say? If your is 35.4dB then you have a better upstream at 46.4 rather than my line attenuation 39.1dB is 30.0 for upstream.
The ISP won't given me GEA TEST say it not available for G.fast only for FTTC
I cannot retrieve those stats from an Openreach g.fast modem.
G.fast can have a GEA test.
Vectoring is enabled on the line stats I posted, it states not monitored on what you posted.
Line stats I gave are on a 3db 2m - 330m downstream, 2m-50m upstream profile.
Line is 199m long estimated.
I just can't see the point of being on a higher tariff if your upstream cannot go higher than 30.
That would be like paying for 80/20 FTTC but only seeing 10 on the upstream.
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I will contact my ISP tomorrow asking if my upstream are banded at 30 if they can removed it off! But on my Zyxel router the data max rate for upstream is still 30?
I don't think it's banded as you are on a SNR of 3dB on the upstream so that's all the speed your line can give.
As an aside my VDSL connection runs at 42/7 as that's all I can get. That speed allows me to have multiple zoom calls and/or HD videos streaming so is perfectly adequate for everyday use. If a large download is being a bit slow I go and make a cup of tea and life goes on. Of course I'd love to have a connection like yours but I can't have one and FTTP won't be where I live for years - it's not even at the planning stage. So when you are worrying about the loss of a few meg on a 200+ Mbps download speed, or the fact that you can only upload at 30 Mbps, just spare a moments thought for the rest of us who can only dream about a connection running that fast.
:)
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as @adslmax is paying for 160/30 and getting exactly what they are paying for.
afaik he's still on the 330/50 product which he upgraded from the 160/30 last week despite recommendations not to.... so is paying the extra £7
adslmax's upload looks to be banded at 30...
Unless I'm missing something, it looks like a normal line limitation. It's syncing at 29359 on SRNm of 3.1 dB. There's nothing left in the line I can see to give more speed. So I can't see any evidence of banding.
The ISP won't given me GEA TEST say it not available for G.fast only for FTTC
Yea goawd why do you need a GEA test anyhow? Stop bothering them there's nothing they can do.
I'm getting bored at the fact that you are still running estimations from the BTW/Openreach checker. >:(
I am also annoyed that you havent got it into your head that these are estimations and they change in line with your current line situation. You are not taking a blind bit of notice of how it works, nor at requests not to keep posting them. You are now using SRA and your line rate will keep changing within about 10Mbps. This is perfectly normal. Your behaviour isn't.
I just can't see the point of being on a higher tariff if your upstream cannot go higher than 30.
He was told exactly that... and he still decided to ignore all advice by going ahead and do so anyway. Max said he understood how SRA worked and he said he understood that he wouldnt get any additional upstream speed. Even his ISP advised him not to, but he insisted and still went ahead.... all for the sake of a variable ~40 Mbps downstream that he doest have any need for.
He is locked into a 12 month contract, the ISP has been good in conversations about what could happen if the line went wrong... but right now it is performing exactly as it should, so this is all he can get.
There is nothing much that can be done - He has locked himself into a 12 mnth contract that will cause a financial loss to the ISP for Max to get out of. I don't want to see any repeat of the situation with Green ISP.
Max has made his choice and paid extra only for the downstream knowing full well that even the downstream can be variable (or should know that its variable). I see absolutely no point in him keep checking checker and checking line stats. He now has to live with that decision for the next year, just like anyone else would.
I don't want to keep seeing stats, I'm not interested. Because of SRA the sync speed will continually change and I have absolutely no interest in seeing stats every time it does change. I've said it before and my patience is wearing thin because I really do have a zillion other things that I should be doing., rather than spending massive amounts of time on a line that is performing as expected. I can't see that there is much left to be said.. this thread and latest stats are pointless.
Max - I've told you to put the Zyxel away and stop chasing stats. Go enjoy your connection that you are paying for and your life would be a lot happier. So would mine.
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Max - I've told you to put the Zyxel away and stop chasing stats. Go enjoy your connection that you are paying for and your life would be a lot happier. So would mine.
I did try put openreach gfast modem but throughput speed down to 94/29 don't know why is this? So, I put Zyxel back and it stay at 221/29. I leave it as it is.
I am now going to do everyone here and kitz a big favour. I won't metion no more of G.fast stats, BTw checker, GEA test, speed test. I know my G.fast are now healthy at 221/29 as I will stay on 330/50 for next 12 months.
I am going to be busy now next week doing back garden and front garden clean up and housework.
You can relax now Kitz. :) Hope u feel better soon. :fingers: