VDSL Sync speed drop

Forums › Spark New Zealand (including Skinny and BigPipe) › VDSL Sync speed drop

kiwipeter

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#150641 29-Jul-2014 09:16

Hi all,

Quick paranoid-type question - when I first got connected to VDSL my router would show sync speed of nearly 40Mbs, and I would obtain very close to that during download. However for the past week or two I have noticed a reduction in download speed and now show a sync speed of 32Mbs.

Should I expect the sync speed to vary this much or should I escalate to Spark support? Maybe they can run a line test?

Thanks,
Peter

PeterReader

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#1097674 29-Jul-2014 09:16

Hello... Our robot found some keywords in your post, so here is an automated reply with some important things to note regarding broadband speeds.

If you are posting regarding DSL speeds please check that

- you have reset your modem and router

- your PC (or other PCs in your LAN) is not downloading large files when you are testing

- you are not being throttled by your ISP due to going over the monthly cap

- your tests are always done on an ethernet connection to the router - do not use wireless for testing

- you read this topic and follow the instructions there.

Make sure you provide information for other users to help you. If you have not already done it, please EDIT your post and add this now:

- Your ISP and plan

- Type of connection (ADSL, ADSL2, VDSL)

- Your modem DSL stats (do not worry about posting Speedtest, we need sync rate, attenuation and noise margin)

- Your general location (or street)

- If you are rural or urban

- If you know your connection is to an exchange, cabinet or conklin

- If your connection is to a ULL or wholesale service

- If you have done an isolation test as per the link above

Most of the problems with speed are likely to be related to internal wiring issues. Read this discussion to find out more about this. Your ISP is not intentionally slowing you down today (unless you are on a managed plan). Also if this is the school holidays it's likely you will notice slower than usual speed due to more users online.

A master splitter is required for VDSL2 and in most cases will improve speeds on DSL connections. Regular disconnections can be a monitored alarm or a set top box trying to connect. If there's an alarm connected to your line even if you don't have an alarm contract it may still try to connect so it's worth checking.

I recommend you read these two blog posts:

- Is your premises phone wiring impacting your broadband performance? (very technical)

- Are you receiving a substandard ULL ADSL2+ connection from your ISP?

I am the Geekzone Robot and I am here to help. I am from the Internet. I do not interact. Do not expect other replies from me.

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kiwipeter

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#1097689 29-Jul-2014 09:19

Hi,

Bit more info.

Netcom NF4V router, diags as below:

Mode:

VDSL2 Annex A

Traffic Type:

PTM

Status:

Link Power State:

Copper Loop(kft):

0.0

Downstream

Upstream

Line Coding(Trellis):

SNR Margin (0.1 dB):

122

155

Attenuation (0.1 dB):

163

Output Power (0.1 dBm):

135

-5

Attainable Rate (Kbps):

32749

12472

Path 0

Path 1

Downstream

Upstream

Downstream

Upstream

Rate (Kbps):

32621

10342

B (# of bytes in Mux Data Frame):

239

237

M (# of Mux Data Frames in an RS codeword):

T (# of Mux Data Frames in an OH sub-frame):

R (# of redundancy bytes in the RS codeword):

S (# of data symbols over which the RS code word spans):

0.2341

0.7307

0.0000

L (# of bits transmitted in each data symbol):

8200

2792

D (interleaver depth):

I (interleaver block size in bytes):

240

255

N (RS codeword size):

240

255

Delay (msec):

INP (DMT symbol):

0.00

Thanks,
Peter

NonprayingMantis

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#1097694 29-Jul-2014 09:29

maybe we should have a peter reader reply that looks for keywords VDSL Sync and replies with something like

"If your VDSL sync rate has dropped over time by a few Mbps, this is perfectly normal and likely due to crosstalk as more and more people take VDSL in your area. It is almost certainly not a fault, and neither your ISP nor Chorus can do anything about it. "

matisyahu

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#1097698 29-Jul-2014 09:36

kiwipeter: Hi all,

Quick paranoid-type question - when I first got connected to VDSL my router would show sync speed of nearly 40Mbs, and I would obtain very close to that during download. However for the past week or two I have noticed a reduction in download speed and now show a sync speed of 32Mbs.

Should I expect the sync speed to vary this much or should I escalate to Spark support? Maybe they can run a line test?

Thanks,
Peter

When did you get your VDSL connection installed? there is a time just after the install where Chorus runs like a fitness test then eventually it settles on the highest speed that is the most stable for your line. Assuming it is outside of that period you might want to check to see where the demark is, how many outlets do you have and where in that chain is your modem hooked up to?

"When the people are being beaten with a stick, they are not much happier if it is called 'the People's Stick'"

kiwipeter

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#1097699 29-Jul-2014 09:36

Hi,

'Peter reader'. Like it!

I did do a bit of research prior to posting, but thought an 8Mbps drop somewhat excessive.

Thanks.

NonprayingMantis

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#1097700 29-Jul-2014 09:40

kiwipeter: Hi,

'Peter reader'. Like it!

I did do a bit of research prior to posting, but thought an 8Mbps drop somewhat excessive.

Thanks.

8Mbps drop is on the high side, but not completely unusual.

If it had dropped below 20Mbps I'd start getting concerned.

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kiwipeter

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#1097701 29-Jul-2014 09:42

When did you get your VDSL connection installed? there is a time just after the install where Chorus runs like a fitness test then eventually it settles on the highest speed that is the most stable for your line. Assuming it is outside of that period you might want to check to see where the demark is, how many outlets do you have and where in that chain is your modem hooked up to?

Thanks for your reply - I have had VDSL for several months, and it settled at around 40Mbps pretty quickly after that (and it stayed constant at that every since). Nothing's changed in the house that might affect the sync speed.

sidefx

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#1097705 29-Jul-2014 09:48

Since the big players started offering VDSL (Telecom, Orcon, VF, etc) mine has dropped from 35 to 28. #waitingforufb :)

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timbosan

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#1097712 29-Jul-2014 09:59

Mine dropped from 43 down to 31, and is still there. I asked my ISP (BigPipe) to get Chorus to check and they said it all looks OK. I have a new master splitter, CAT5e cable, etc. It's just one of those things we have to live with I guess as more people more to VDSL.

johntynz

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#1097885 29-Jul-2014 13:48

my neighbour connected to vdsl, I dropped by about 8mb aswell... it happens, nothing can be done :(

hio77

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#1097923 29-Jul-2014 14:57

sounds verymuch like DLM or crosstalk at play.

gezz hearing all these horror stories of all your drops! happily holding my 58/10 ;)

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Athlonite

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#1100782 2-Aug-2014 18:34

My Orcon VDSL was at 35Mbps it's 28Mbps now I must find out which neighbour it is and disconnect them thieving buggers I want my 7Mbps back as I have been noticing 1080p youtube vids stutering now

hio77

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#1100784 2-Aug-2014 18:37

Athlonite: My Orcon VDSL was at 35Mbps it's 28Mbps now I must find out which neighbour it is and disconnect them thieving buggers I want my 7Mbps back as I have been noticing 1080p youtube vids stutering now

ouch..

guess the covenant thing about my area, is its mostly older people, less likely to go vdsl!

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Athlonite

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#1101051 3-Aug-2014 12:35

Yes Ouch indeed yeah unfortunately for me it's a mixed bag of elderly, young and families round my area so I wish Chorus would hurry up already with the UFB roll out past my door