Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Pages: [1] 2

Author Topic: VDSL2 Woes  (Read 6234 times)

TomPoolHD

  • Member
  • **
  • Posts: 13
VDSL2 Woes
« on: May 31, 2017, 09:27:12 PM »

Today I had VDSL installed, and the speeds seem to be somewhat interesting.

The line is rather long and I didn't expect huge speeds but at 2km from the cabinet I think a 3000kbps sync is a little lower than expected. Im connected to Malton exchange on cabinet 9.

I just wondered if anyone can deduce any information from my line stats and mydslwebstats data that I have started to upload.

mydslwebstats username: TomPoolHD
Line stats: http://imgur.com/7plrT2U

Any help is greatly appreciated!

Thanks Tom
Logged

burakkucat

  • Respected
  • Senior Kitizen
  • *
  • Posts: 38300
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: VDSL2 Woes
« Reply #1 on: May 31, 2017, 10:17:27 PM »

Hello Tom. Welcome to the Kitz forum.  :)

Having taken a quick look at the information your have provided, along with viewing MDWS, it does seem as if you have a circuit that is at the "far limit" for a G.993.2 (VDSL2) based Internet service. I think we need to let the circuit "do its own thing" and then review the situation after 24 hours have elapsed.

Being a new provision, the circuit is running on fast-path with a "wide open" profile. I suspect that once the first 24 hours have elapsed the DLM will then attempt to optimise the circuit's performance.

I may be wrong but I thought that Ofcom had issued a diktat that all ISPs/CPs must provide a personalised estimate as to the performance one could expect when signing up for their service. So if I'm not imagining it what estimate did your ISP/CP provide, please?

Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

forceware

  • Member
  • **
  • Posts: 81
Re: VDSL2 Woes
« Reply #2 on: May 31, 2017, 10:25:44 PM »

Hi, I am 1.9km from my eci cabinet and I get 16 down and 0.5 up. I have to limit it to 10 down or I get horrendous amounts of interleaving applied.
Logged

Dray

  • Kitizen
  • ****
  • Posts: 2361
Re: VDSL2 Woes
« Reply #3 on: May 31, 2017, 10:38:57 PM »

Hi Tom, is that a Zyxel modem?
Logged

TomPoolHD

  • Member
  • **
  • Posts: 13
Re: VDSL2 Woes
« Reply #4 on: May 31, 2017, 10:56:36 PM »

Hi Tom, is that a Zyxel modem?
It's a Billion 8900AX 2400.
I may be wrong but I thought that Ofcom had issued a diktat that all ISPs/CPs must provide a personalised estimate as to the performance one could expect when signing up for their service. So if I'm not imagining it what estimate did your ISP/CP provide, please?
Great to be here, thanks.
I think the clean estimate was 4.7 Mbps downstream, impacted 2Mbps. AAISP have the range of 2-10.7 as they Quote from the bottom of impacted to the top of clean estimate.
Logged

burakkucat

  • Respected
  • Senior Kitizen
  • *
  • Posts: 38300
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: VDSL2 Woes
« Reply #5 on: May 31, 2017, 11:21:30 PM »

I think the clean estimate was 4.7 Mbps downstream, impacted 2Mbps. AAISP have the range of 2-10.7 as they Quote from the bottom of impacted to the top of clean estimate.

Thank you.

Ah, yes, I had read that A&A tend to quote a rather optimistic wide range. My feeling -- with the sparse amount of data that is currently available to us -- is that around 3 Mbps DS may be the upper limit for your circuit.
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

banger

  • Kitizen
  • ****
  • Posts: 1186
  • TTB 80/20
Re: VDSL2 Woes
« Reply #6 on: May 31, 2017, 11:51:15 PM »

Blimey 2km to the cab. I didn't think it was possible, would you not be better off with ADSL2+ Tom?
Logged
Tim
talktalkbusiness.net & freenetname
Asus RT-AC68U and ZyXEL VMG1312-B10A Bridge on 80 Meg TTB Fibre

https://www.thinkbroadband.com/speedtest/1502566996147131655

TomPoolHD

  • Member
  • **
  • Posts: 13
Re: VDSL2 Woes
« Reply #7 on: June 01, 2017, 09:04:50 AM »

Blimey 2km to the cab. I didn't think it was possible, would you not be better off with ADSL2+ Tom?

ADSL was giving a speed of around 5Mbps so yep at the moment it looks that way.

On the plus side an engineer arrived this morning and has found a battery fault, and something to do with a bad earth. I'm not entirely sure but he is checking everything so fingers crossed we could see some more speed!
Logged

stevebrass

  • Reg Member
  • ***
  • Posts: 261
Re: VDSL2 Woes
« Reply #8 on: June 01, 2017, 12:39:56 PM »

I am km from the cabinet and get 15/1 with latency about 20. The happy days of G.inp gave me 18/1 and 15.
Logged
Netgear Orbi; BT FTTP with Smart Hub 2

burakkucat

  • Respected
  • Senior Kitizen
  • *
  • Posts: 38300
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: VDSL2 Woes
« Reply #9 on: June 01, 2017, 03:59:02 PM »

On the plus side an engineer arrived this morning and has found a battery fault, and something to do with a bad earth.

It will either be a "battery contact fault" or an "earth contact fault". I'd be surprised if both types of fault were found . . . but then I'm not the Openreach technician tasked with the fault.  :)  (And that explains the cessation of uploads to MDWS at 0839 hours this morning.)

I will be very interested to see the resultant Hlog and QLN plots once the work is complete -- I hope to see an improvement.

Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

TomPoolHD

  • Member
  • **
  • Posts: 13
Re: VDSL2 Woes
« Reply #10 on: June 01, 2017, 04:24:15 PM »

It will either be a "battery contact fault" or an "earth contact fault". I'd be surprised if both types of fault were found . . . but then I'm not the Openreach technician tasked with the fault.  :)  (And that explains the cessation of uploads to MDWS at 0839 hours this morning.)

I will be very interested to see the resultant Hlog and QLN plots once the work is complete -- I hope to see an improvement.

I'm going to setup the computer again to record the results. Sadly no gain in speed from the fault being fixed but hopefully errors reduced or some effect on the quality of the broadband  :)
« Last Edit: June 01, 2017, 04:26:53 PM by TomPoolHD »
Logged

burakkucat

  • Respected
  • Senior Kitizen
  • *
  • Posts: 38300
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: VDSL2 Woes
« Reply #11 on: June 01, 2017, 04:37:40 PM »

Uploading to MDWS is, once again, in progress.

I was hoping to see an improvement in both the Hlog and QLN plots . . .

The latter still looks like a fine-tooth flea-comb.  :-X
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

TomPoolHD

  • Member
  • **
  • Posts: 13
Re: VDSL2 Woes
« Reply #12 on: June 01, 2017, 04:50:38 PM »

Uploading to MDWS is, once again, in progress.

I was hoping to see an improvement in both the Hlog and QLN plots . . .

The latter still looks like a fine-tooth flea-comb.  :-X

I thought we had cracked it with the battery fault, seems not  :(

The SFI engineer said his final tests said the line was perfect. I'm not sure what to do now...

AAISP have said they will continue to chase it up, hopefully they can find something else that might be causing the problem.

In regards to the upstream speed is that in any way related with the downstream speed? Like a correlation, as I can see another user on mydslwebstats is also at the end of a long line recieving around 10Mbps down and 1Mbps up. Im not great with the technical side of broadband but I think it's best to analyse as much as possible to see if there is an underlying problem and comparison with another long line may help.

Thanks Tom
Logged

burakkucat

  • Respected
  • Senior Kitizen
  • *
  • Posts: 38300
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: VDSL2 Woes
« Reply #13 on: June 01, 2017, 05:06:46 PM »

In regards to the upstream speed is that in any way related with the downstream speed? Like a correlation, as I can see another user on mydslwebstats is also at the end of a long line recieving around 10Mbps down and 1Mbps up. Im not great with the technical side of broadband but I think it's best to analyse as much as possible to see if there is an underlying problem and comparison with another long line may help.

The DS and US synchronisation and throughput speeds are related to the loop-loss (the attenuation) of the circuit . . . Strictly, it is an inverse relationship.

We need to watch and wait, as the circuit has not yet had a full 24 hours of operation.

Quote from: BT SIN498
2.2 User Network Interface - General

2.2.1 Dynamic Line Management

Dynamic Line Management (DLM) is employed in GEA-FTTC. DLM constantly
manages lines to maintain a target link quality (speed and stability). It does this for as
long as the product exists.

At provision, the line is put on “wide open” VDSL2 line profiles allowing the
upstream and downstream line speeds to run at the upper limit of the product option
selected.

On the first day of operation, DLM will intervene if severe instability is detected.
Otherwise, DLM will wait until the day after provision before deciding if it must
intervene, provided that the line has been trained up for at least 15 minutes during the
preceding day.

If DLM intervenes it will set a profile with a maximum rate and a minimum rate,
where the minimum rate is set at approximately half of the maximum rate. The
purpose of the minimum rate is to ensure that the line does not train at a rate which is
significantly below the level the line should be able to achieve. If this happened, then
the line is likely to remain at a very low rate until a re-train is forced by the user by
powering off the modem.

Note : It is the DLM system that sets the line profile, and this should not be interfered
with by CPs/users setting rates, SNR margins etc. at the modem.

Note : The upstream throughput is also constrained on the DSLAM to the upstream
rate requested in the order, i.e. 2 Mbit/s, 10 Mbit/s or 20 Mbit/s, so even if the VDSL2
upstream line speed is higher, the upstream throughput is constrained to the level
ordered for the product.

SIN 498 v7.3
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

TomPoolHD

  • Member
  • **
  • Posts: 13
Re: VDSL2 Woes
« Reply #14 on: June 01, 2017, 05:18:06 PM »

The DS and US synchronisation and throughput speeds are related to the loop-loss (the attenuation) of the circuit . . . Strictly, it is an inverse relationship.

We need to watch and wait, as the circuit has not yet had a full 24 hours of operation.

SIN 498 v7.3

Ah ok thanks for that!

The engineer also mentioned he had preformed a DLM reset. Am I right in thinking G.INP could be placed on the line? That could bring some more speed :)
Logged
Pages: [1] 2