Sync Speed vs Speed Test (ADSL2+)

I recently moved from O2 to Plusnet and I have noticed the following hope someone can help clarify.

- With sync speed of say 6518 kbps what should I expect from speed tests. I am getting between 4.4 - 4.6 Mbps. With O2 it was lot closer to the sync speed. I have tried various speed site and computers ...same results.
- The same for upload around .86 Mbps

Router - Technicolor TG582n (ordered a billion 7800N)
DSL Connection -
DSL Type: ITU-T G.992.5

Bandwidth (Up/Down) [kbps/kbps]: 1.046 / 6.518

Data Transferred (Sent/Received) [MB/MB]: 64,82 / 133,49

Output Power (Up/Down) [dBm]: 12,6 / 0,0

Line Attenuation (Up/Down) [dB]: 24,8 / 41,0

SN Margin (Up/Down) [dB]: 6,1 / 3,9

System Vendor ID (Local/Remote): TMMB / ----

Chipset Vendor ID (Local/Remote): BDCM / IFTN

Loss of Framing (Local/Remote): 9 / 0

Loss of Signal (Local/Remote): 1 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): -

Error Seconds (Local/Remote): 13 / 0

FEC Errors (Up/Down): 379 / 24.135

CRC Errors (Up/Down): 0 / 3

HEC Errors (Up/Down): 0 / 2

Actually your line is underperforming: one might expect a minimum ADSL2+ downstream sync of 7552Kbps with a 6dB SNRM on an attenuation of 41dB. Yet your router is reporting a SNRM of 3.9dB which should enable an even faster sync speed.

Possibly you may have a home wiring issue: if you have any phone extensions from the master NTE5 faceplate have you removed the bell wire(s)? The bell wire can introduce noise on the line and reduce it's full potential...

throughput is normally ~86% of sync so those speeds are normal

there is some slight noise present indicated by the 3.9 decibel (DOWN SNR) but shouldnt cause any worry

just for the hell of it can you explain your setup from the master socket .. i.e any extensions, sky boxes or fax machine and extra corded/cordless phones in the property?

Thanks for your replies.

My router is connected directly to the master socket. No extension or any other type of kit connect to it. The master socket is newly (today) fitted openreach socket.

Comment on plusnet support site is...

"Loop loss of 40db - this needs the SNR target to be raised to at least 6db as 3db is causing DCN, errors and throughput speed issues."

Not sure what this will do...

Have you got any alternative micro filters (dangle filters) and an ADSL lead that you try?

BTW. what operating system are you using on your computer?

The BT engineer actually replaced the socket today to rule things out. I have the RJ11 cable directly into the wall socket without any dangle filters.

The operating system is Windows 7.

In reply to a post by afsar:

My router is connected directly to the master socket.

Best to repeat all those readings from the hidden test socket behind the removable faceplate. This takes all other factors out the equation for starters.

As a rule of thumb, I reckon Throughput = ~ 83% Sync speed. So your down throughput is a bit down; should be ~ 5.4 Meg, but Up speed is spot-on.

As others have pointed out, your line is underperforming. Should sync at ~ 8.6 Meg.

Sometimes those filtered faceplates can be more unreliable than danglers. Still try from test socket with dangler.

In reply to a post by afsar:

The BT engineer actually replaced the socket today to rule things out. I have the RJ11 cable directly into the wall socket without any dangle filters.

The operating system is Windows 7.

Ah, so the engineer fitted a filtered faceplate also - those filtered faceplates have been known to cause problems. Can you remove the filtered faceplate and use either a modem lead or a dangle filter + RJ11 cable from the NTE5 test socket to the router. And also reboot the router? Maybe the sync speed and SNRM might be optimised if you do that...

If the computer OS was XP then there could have been some issues with ADSL2+ throughput speed, but Win7 should be OK

I was getting throughput of 5+ Meg on O2 with exact same set-up (apart from the router) so not sure why same cannot be archived on plusnet.

Output from site - http://www.dslchecker.bt.com/adsl/adslchecker.welcome.

Telephone Number 01484xxxxxx on Exchange HUDDERSFIELD is served by Cabinet 13
Available Products

Downstream Line Rate(Mbps)

Upstream Line Rate(Mbps)

Downstream Range(Mbps)

Availability Date

Featured Products

WBC ADSL 2+ Up to 11 -- 9.5 to 12.5 Available
WBC ADSL 2+ Annex M Up to 11 Up to 1 9.5 to 12.5 Available
ADSL Max Up to 5 -- 3.5 to 7.5 Available
WBC Fixed Rate 2 -- -- Available
Fixed Rate 2 -- -- Available

Stats from test socket...

DSL Type: ITU-T G.992.5

Bandwidth (Up/Down) [kbps/kbps]: 1.073 / 6.475

Data Transferred (Sent/Received) [MB/MB]: 107,30 / 471,35

Output Power (Up/Down) [dBm]: 12,6 / 0,0

Line Attenuation (Up/Down) [dB]: 24,9 / 41,0

SN Margin (Up/Down) [dB]: 5,6 / 3,3

System Vendor ID (Local/Remote): TMMB / ----

Chipset Vendor ID (Local/Remote): BDCM / IFTN

Loss of Framing (Local/Remote): 34 / 0

Loss of Signal (Local/Remote): 4 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): -

Error Seconds (Local/Remote): 60 / 0

FEC Errors (Up/Down): 0 / 1.216

CRC Errors (Up/Down): 0 / 0

HEC Errors (Up/Down): 0 / 0

Was O2 an ADSL MAX connection?

In reply to a post by afsar:

Stats from test socket...

DSL Type: ITU-T G.992.5

Bandwidth (Up/Down) [kbps/kbps]: 1.073 / 6.475

Data Transferred (Sent/Received) [MB/MB]: 107,30 / 471,35

Output Power (Up/Down) [dBm]: 12,6 / 0,0

Line Attenuation (Up/Down) [dB]: 24,9 / 41,0

SN Margin (Up/Down) [dB]: 5,6 / 3,3

Looks like noise affecting the ADSL2+ frequencies somewhere between the NTE5 and the exchange - router might be at fault, though unlikely...

Push Plusnet to investigate further...

Bandwidth (Up/Down) [kbps/kbps]: 1.073 / 6.475
Line Attenuation (Up/Down) [dB]: 24,9 / 41,0
SN Margin (Up/Down) [dB]: 5,6 / 3,3

Can you flip the ADSL mode to ADSL2 or G.dmt for comparison. That sync speed is a bit low for the attenuation as others have pointed out, despite the low target margin.

Sounds like PN are going to increase the target margin and cost you a bit of speed.

Can you confirm there are no wired extensions, bells, alarms etc on the wiring ?

Not sure. Had it for several years. Only reason I changed was it started to drop connections in the last few months and their support was not pushing for resolution. Other than this O2 was fine for last 2 years or so.

In reply to a post by afsar:

Only reason I changed was it started to drop connections in the last few months and their support was not pushing for resolution.

!!!

Nothing connected other the R11 and the phone.

The point of their investigation is to improve speed. I do not have stability issues so hope it does not slow things ...this is their comment "...you should be seeing the improvements today".

Regarding the modes I am using standard plusnet modem/router and cannot see option to switch. I have ordered a Billon 7800N but its not arrived yet.

when the downstream SNR margin goes to 6 you'll know the changes are in place. The sync speed will reduce, but it's possible the throughput will improve if there were a lot of errors.

Hi afsar,

Can you message me over your username and I'll take a look at that for you?

Chris

update....

Just got my Billion 7800N delivered and go this connected instead of the plusnet device and the stats is 864 / 7442 kbps (sorry dont know how to get detail info yet). Download sync gone up by over 1000 but actual throughput remains the same 4.4 - 4.5 meg .

In reply to a post by afsar:

update....

Just got my Billion 7800N delivered and go this connected instead of the plusnet device and the stats is 864 / 7442 kbps (sorry dont know how to get detail info yet). Download sync gone up by over 1000 but actual throughput remains the same 4.4 - 4.5 meg .

Google is great...here is detail stats...

> adsl info --stats
adsl: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 864 Kbps, Downstream rate = 9280 Kbps
Path: 0, Upstream rate = 864 Kbps, Downstream rate = 7442 Kbps

Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 4.0 14.6
Attn(dB): 42.0 25.5
Pwr(dBm): 0.0 12.8
ADSL2 framing
MSGc: 59 64
B: 232 13
M: 1 8
T: 1 2
R: 16 16
S: 0.9974 4.0000
L: 1997 256
D: 32 8
Counters
SF: 52348 48413
SFErr: 0 0
RS: 3402638 847235
RSCorr: 4642 0
RSUnCorr: 0 0

HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 14889078 1716764
Data Cells: 183249 60826
Drop Cells: 0
Bit Errors: 0 0

ES: 0 0
SES: 0 0
UAS: 206 206
AS: 849

INP: 1.02 2.00
PER: 16.20 17.50
delay: 7.97 8.00
OR: 32.08 32.00

Bitswap: 30 1

Total time = 20 min 57 sec
FEC: 4642 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 206 206
LOS: 0 0
LOF: 0 0
Latest 15 minutes time = 5 min 57 sec
FEC: 2757 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 1885 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 206 206
LOS: 0 0
LOF: 0 0
Latest 1 day time = 20 min 57 sec
FEC: 4642 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 206 206
LOS: 0 0
LOF: 0 0
Previous 1 day time = 0 sec
FEC: 0 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Since Link time = 14 min 7 sec
FEC: 4642 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0

In reply to a post by afsar:

...actual throughput remains the same 4.4 - 4.5 meg .

That could be because your profile has not been updated at the PN end yet...

If your connection will stay up, try:

adsl configure -snr 50

50 should give 3dB SNR as opposed to 6dB. A value of 75 would be 4.5dB. If your line is good for it (stable), you might get 0.5 to 1.5 Meg faster.


Edit: Woah! Your SNR is currently 4.0 anyway. I wouldn't try that tweak after all. Strange value.

Edited by camieabz (Wed 27-Feb-13 16:29:43)

Is there anyway to tell which profile I am on ? and how frequently does this change?

http://speedtester.bt.com/ will show you the BT profile on the advanced diagnostics page, I think the Plusnet profile is accessible via the user portal (?)

In reply to a post by yarwell:

http://speedtester.bt.com/ will show you the BT profile on the advanced diagnostics page, I think the Plusnet profile is accessible via the user portal (?)

Thanks yarwell.

Looks like profile has changed by around 1.5 meg but throughput has not from doing speed tests.

Download speedachieved during the test was - 4.42 Mbps
For your connection, the acceptable range of speeds is 2 Mbps-7.15 Mbps.
IP Profile for your line is - 6.57 Mbps

Upload speed achieved during the test was - 0.74Mbps
Additional Information:
Upstream Rate IP profile on your line is - 0.83 Mbps

Your profile was set to 4.6Mb/s, I've adjusted that now to match accordingly. Give it 10-15 minutes and try it again.

Post deleted by timl

In reply to a post by chrispurvey:

Your profile was set to 4.6Mb/s, I've adjusted that now to match accordingly. Give it 10-15 minutes and try it again.

Maybe a dumb question but why would my profile be set to a limit (4.6Mb/s) in first place?

Thank you for your help. The throughput is above 5.5 meg and lot closer to the sync speed.

DSP Firmware Version A2pB025f.d22k
DMT Status No Defect
Operational Mode ADSL2+
Upstream 864
Downstream 6490
SNR Margin(Upstream) 14.3
SNR Margin(Downstream) 6.6
Line Attenuation(Upstream) 25.4
Line Attenuation(Downstream) 41.5

The sync has come down by 1000 I guess this is due to the increase in the SNR (6.6) ?

Plusnet have their own system which they set to the IP profile set by BT. This helps their traffic management system correctly prioritize packets for you. It's actually a good thing... except when it doesn't pick up the BT IP profile... as in your case.

Because Plusnet mirror the IP Profile as seen by BT Wholesale and in the short time frame of this thread would probably not have had the notificaiton that it had changed at the BT Wholesale level

In reply to a post by afsar:

DSP Firmware Version A2pB025f.d22k
DMT Status No Defect
Operational Mode ADSL2+
Upstream 864
Downstream 6490
SNR Margin(Upstream) 14.3
SNR Margin(Downstream) 6.6
Line Attenuation(Upstream) 25.4
Line Attenuation(Downstream) 41.5

Unfortunately your line is still under performing; really you should be seeing at least a downstream sync of 7552Kbps with a 6dB SNRM on an ADSL2+ attenuation of 41dB.

Probably best just to monitor the line for stability for the time being...

Thank you to all for the help today much appropriated.

The new router is great...was not sure whether to buy but seems to be working great. I have managed to play with SNR. Got it to this...

DSP Firmware Version A2pB025f.d22k
DMT Status No Defect
Operational Mode ADSL2+
Upstream 864
Downstream 7314
SNR Margin(Upstream) 14.2
SNR Margin(Downstream) 2.7
Line Attenuation(Upstream) 25.5
Line Attenuation(Downstream) 41.5

SNR is low but i'll see how this router handles it.

Speed Test

Thank you again to everyone.

This http://www.thinkbroadband.com/speedtest/button/13619... is currently on my ADSL2+ partial LLU line 37dB attenuation, 6dB SNRM and 13358Kbps sync.

So even though your downstream attenuation is greater and SNRM is lower your line is not performing at it's full potential.

Keep monitoring and if there is no improvement then chase up PN about it