Strange speed increase

Im on bt option 3 with fibre as I'm about 1000m from the cab, anyway for the last few months I've been getting 21 mb down. After flashing the modern my maximum line attainable was reported at 28mb, the checker told me I would only get 7 mb down I was over the moon with 21mb, and this is how it's stayed for three months.
Just checked the stats this morning and now my maximum attainable is 41mb down and I'm syncing at 32mb with an snr of 7.5, anyone else had anything like this happen?.

Edited by Cottee55 (Fri 21-Oct-11 11:28:52)

People in this thread quoting various changes.

My actual speed hasn't changed (although I may try a modem reboot).

Also, what does the checker say for you now?

Edited by mikecrawford80 (Fri 21-Oct-11 11:00:40)

Just checked and it now says I can get 13.2mb so it's gone up, shame as if it was over 15mb I could of got them to switch me to infinity.

If you want the higher upload then plenty of other ISPs will let you have it, even if BT limit you to the 2Mbps. As for the download, Infinity would make no difference.

What ever has happened my ip profile is now stuck at 32339, so maybe they have upgraded something in the cab or the exchange And my line must of kept resyncing. At the best I could download at 2.8 but now I'm getting 4.2 so really happy with what ever they have done.

Edited by Cottee55 (Fri 21-Oct-11 11:40:28)

I think the change may be one of 2 things;

1. BT catching up with real-life speeds as more and more lines have FTTC activated on them, so they are able to give better estimates
2. VDSL2 profile 17a kicking in

Thoughts anyone?

It's number 2.

17a is now enabled on my line and we gained about 6Mbit extra

My data on the checker has gone from 14.7 d/s to 23.8, which is a lot closer to my actual real world speed of 28ish Mb/s. Upstream however says 5.8, (I can't remember if the checker ever gave an u/s figure ?) but actual is 8ish Mb/s

In reply to a post by orly:

It's number 2.

Agreed. I didn't realise the posters weren't aware of this thread.

In reply to a post by orly:

It's number 2.

17a is now enabled on my line and we gained about 6Mbit extra

Hi Orly,

Just for curiosity, what was your pre-install estimated speed?
Mine was 14.6Mb & it has just this week gone up to 24Mb.

I have had all sorts of issues with my connection that my ISP said couldn't be reported to BT as my speed was above the estimate.
Well, now they [censored] well can.

I started off with 33Mb actual downloads that dropped to as low as 7Mb at one point.

My current download speeds are around 19.5Mb.

Paul.

P.S. Did anyone notify you of the switch to 17a profile, or did it just happen as if by magic?

P.P.S. I have reboted my modem, but am still using profile 8c.

Edited by Bald_Eagle1 (Fri 21-Oct-11 21:40:44)

Mine now may be stuck - sync'd at 33723 but not reaching attainable rate which has gone up a little to 39676~ (this evening), was lower before.

My original DS estimate was 14.6, revised to 23.1 - maybe 17a as mentioned.

Not good if it's stuck now though, as I had an IP profile of 36632 before, so going the wrong way!

Will see how it goes for a week or so, and ask about getting it unstuck. Depends what they did to the cab.

In reply to a post by Cottee55:

What ever has happened my ip profile is now stuck at 32339, so maybe they have upgraded something in the cab or the exchange And my line must of kept resyncing. At the best I could download at 2.8 but now I'm getting 4.2 so really happy with what ever they have done.

17a is now enabled on my line and we gained about 6Mbit extra

Really ? How are you getting that data ?

Zarjaz, they are pulling it from the cracked firmware flashed into the OR Modem and logging in via Telnet/Putty.

If anyone is interested there is a bit more info here:-
FTTC 80/20 Updates

From our modem.

It started off, way back when, at something like 16Mbit. Then after we got it installed the estimate went up to 27Mbit (the speed we got when the engineer installed it)

Cheers Orly,

How stable does it seem using profile 17a & what are your actual download speeds like compared to 8c?

Paul.

We started off at 27Mbit as mentioned and it gradually dropped down to 23.5Mbit which was the "stable" speed. Upload was 8Mbit.

On 17a it's up to 29Mbit but the upload has dipped to 6Mbit. The estimate for upload is now 11Mbit though so it's a bit strange.

The thing being that although you see a profile change, I have seen nowt using an 'official' tester. I just wonder if it's some other tweak which is causing the reported changes.

to be fair, I have only seen the 17a profile change on longer lines and people with low connections,

Seems very clearly the 17a profile causing it here looking at the linediag command and seeing the frequencies in use.

Can you post the relevant stats / screenshots for us to examine? thanks.

Hi Orly,

Have you collected yor stats again, now that profile 17a has been used for a few days on your connection?

Most users seem to be seeing that profile 17a is now being "detected" at Discovery Phase (Initial) Band Plan, but not "fully" used at Medley Phase (Final Band Plan)

My guess is either line/signal attenuation is simply too high (distance from the cabinet), or more likely that the current BT 40Mb cap won't allow any throughput at the higher profile 17a frequencies:-

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 6157 Kbps, Downstream rate = 6352 Kbps
Path: 0, Upstream rate = 6160 Kbps, Downstream rate = 30000 Kbps

Discovery Phase (Initial) Band Plan
US: (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) (1216,1963)

VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 6157 kbps 6352 kbps
Actual Aggregate Tx Power: 2.5 dBm 11.6 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 8.5 47.2 63.8 N/A 20.1 57.6 0.1
Signal Attenuation(dB): 10.6 46.6 N/A N/A 20.1 57.6 N/A
SNR Margin(dB): 6.1 6.3 N/A N/A -7.7 -7.1 N/A
TX Power(dBm): -8.4 2.2 N/A N/A 10.0 6.5 N/A



Paul.

Edited by Bald_Eagle1 (Sun 23-Oct-11 21:49:36)

OK, seen 17A profile on a line myself today. Might just go get the tester from the van and try my own line later ........

xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 6107 Kbps, Downstream rate = 33460 Kbps
Path: 0, Upstream rate = 6104 Kbps, Downstream rate = 30000 Kbps

Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 7.9 6.2
Attn(dB): 0.0 0.0
Pwr(dBm): 11.7 2.3

What phase of the rollout was your exchange in orly?

Hi All,

My exchange was in Phase 2.

I noticed that my profile had switched from 8c to 17a in the early hours of this morning.

Before the switch :-

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 6454 Kbps, Downstream rate = 23608 Kbps
Path: 0, Upstream rate = 6435 Kbps, Downstream rate = 20345 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (696,1183)
DS: (32,687) (1192,1627)
Medley Phase (Final) Band Plan
US: (0,95) (696,1183)
DS: (32,687) (1192,1627)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 6454 kbps 23608 kbps
Actual Aggregate Tx Power: 3.2 dBm 9.6 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 8.6 52.0 N/A N/A 21.5 65.0 N/A
Signal Attenuation(dB): 14.0 51.7 N/A N/A 21.5 65.0 N/A
SNR Margin(dB): 5.9 5.9 N/A N/A 6.2 6.4 N/A
TX Power(dBm): -9.3 2.9 N/A N/A 9.1 -0.1 N/A


After the switch:-

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 4654 Kbps, Downstream rate = 29588 Kbps
Path: 0, Upstream rate = 4647 Kbps, Downstream rate = 25975 Kbps

Discovery Phase (Initial) Band Plan
US: (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) (1216,1963)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 4654 kbps 29588 kbps
Actual Aggregate Tx Power: 6.3 dBm 12.0 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 8.4 55.7 64.3 N/A 22.4 65.3 0.1
Signal Attenuation(dB): 14.3 55.0 N/A N/A 22.4 65.3 N/A
SNR Margin(dB): 6.3 6.3 N/A N/A 5.6 5.6 N/A
TX Power(dBm): -4.2 5.8 N/A N/A 10.8 5.3 N/A

A bit of a hit on the Upstream, but an increase on the downstream.

Getting Zilch from the new higher frequency bands though.

Probably due to high attenuation caused by a high resistance fault still present on my line (supposedly fixed ages ago), or that BT still have me capped at a low profile due to all the previous connection issues.

I was manually capped at 25Mb at one point.
Maybe one part of BT hasn't told another part of BT that the faults have been fixed?

My ISP seems too reluctant to even ask BT to try my connection at 40Mb again & I'm not ALLOWED to speak to BT directly myself!!!!!!.

Paul.

Edited by Bald_Eagle1 (Fri 28-Oct-11 11:55:34)

In reply to a post by Bald_Eagle1:

My exchange was in Phase 2.

Thanks. Me too, hopefully won't be long till it changes here aswell.

In reply to a post by Bald_Eagle1:

I'm not ALLOWED to speak to BT directly myself!!!!!!.

I can sympathise there, ISPs are piggy in the middle, very frustrating

Maybe moving to aaisp (who are apparently very good at getting bt to fix faults) untill it's fixed and then back to your prefered ISP is your only option now.

Edited by Croftie (Fri 28-Oct-11 16:43:12)

In reply to a post by Croftie:

Maybe moving to aaisp (who are apparently very good at getting bt to fix faults) untill it's fixed and then back to your prefered ISP is your only option now.

Hi Croftie,

I am tied in to an 18 month contract, so moving to AAISP would be quite expensive at this stage, especially as AAISP seem to be quite a bit more expensive for my type of internet useage.

I have considered that though, as all the time I have spent trying to get this resolved has some cost attached to it. I still haven't ruled it out.

I actually quite like my current ISP (Plusnet) despite what may have been construed elsewhere.
At least they haven't just given up on me like some others would.
They have got close a couple of times, but are still in there with me (sort of)

Good luck when it's your turn for the 17a switch & keep us posted on how it goes.
I don't know whether or not the switch is based on geographical areas but FYI, my exchange is Oldham.


Paul.

In reply to a post by Bald_Eagle1:

Before the switch :-

Discovery Phase (Initial) Band Plan
US: (0,95) (696,1183)
DS: (32,687) (1192,1627)

=============================================

After the switch:-

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)

==============================================

A bit of a hit on the Upstream, but an increase on the downstream.

Those numbers in the band plan show another significant change... BT haven't just switched the profile from 8c to 17a, but they've also switched the bandplan from 997 to 998.

As you've noticed, the significant difference (below 7MHz) is to steal 0.6MHz from upstream, and give it to downstream: Downstream gains the bandwidth from 3.0MHz to 3.7MHz, but loses the bit between 5.1MHz and 5.2MHz.

The next significant difference is that the first 1.5MHz of the new bandwidth (up to 8.5MHz) also goes to the downstream in the 998 plan; with 997 it would have gone to upstream.

Seems like BT have chosen to focus *more* onto the downstream deliberately.