Massive bandwidth drop after change of plan from 150GB to 500GB

Forums › Spark New Zealand (including Skinny and BigPipe) › Massive bandwidth drop after change of plan from 150GB to 500GB

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Jase2985

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#1107823 13-Aug-2014 17:35

sounds like you dont know much about how VDSL works :) VDSL has bits in common with other types of DSL but there is a whole other part to it.

DLM is dynamic, you have a 10day training period after a port reset when DLM tires to give you the most stable line with out sacrificing too much on speed. in that 10 days you may see a couple of resyncs and changes in speed. this generally lowers your ping and sometimes lowers your bandwidth. after the 10 days thats normally the DLM profile/sync speed you are stuck on. I havent seen many people go up in sync speeds after the 10 day peroid, the only exception is if they go from a 8B band plan to a 17A band plan, which as pointed out earlier requires those 3 factors.

you havent posted up your INP or delay stats so we dont know what DLM profile you are on so we cant really give you too much more info on how your line will end up.

FYI, i lost 17A about 2.5 months ago due to a line fault, i started back on 53Mbps then dropped to 52Mbps but gained about 16ms less ping.

The fact that more people are hopping on VDSL because they cant get fiber means those with high sync speeds start loosing those speeds and those with low speeds loose those speeds too.

there is nothing really you can do if the wiring in your house is up to scratch. it is what it is and thats a best effort service.

hio77

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#1107832 13-Aug-2014 17:41

Jase2985: sounds like you dont know much about how VDSL works :) VDSL has bits in common with other types of DSL but there is a whole other part to it.

DLM is dynamic, you have a 10day training period after a port reset when DLM tires to give you the most stable line with out sacrificing too much on speed. in that 10 days you may see a couple of resyncs and changes in speed. this generally lowers your ping and sometimes lowers your bandwidth. after the 10 days thats normally the DLM profile/sync speed you are stuck on. I havent seen many people go up in sync speeds after the 10 day peroid, the only exception is if they go from a 8B band plan to a 17A band plan, which as pointed out earlier requires those 3 factors.

you havent posted up your INP or delay stats so we dont know what DLM profile you are on so we cant really give you too much more info on how your line will end up.

FYI, i lost 17A about 2.5 months ago due to a line fault, i started back on 53Mbps then dropped to 52Mbps but gained about 16ms less ping.

The fact that more people are hopping on VDSL because they cant get fiber means those with high sync speeds start loosing those speeds and those with low speeds loose those speeds too.

there is nothing really you can do if the wiring in your house is up to scratch. it is what it is and thats a best effort service.

the 10 day training period is simply 10 days where they poll at an increased rate, and in turn, profile changes are pushed far more rapidly.

after that the same system is at play, its just much slower at deciding on a move.

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Jase2985

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#1107837 13-Aug-2014 17:44

just checked and i have less than 7 days of my 90 remaining, i dont think i will get back onto 17A though

hio77

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#1107838 13-Aug-2014 17:45

Jase2985: just checked and i have less than 7 days of my 90 remaining, i dont think i will get back onto 17A though

thats not to say it will take an extra month to move to 17a though. or even that your 100% likely to flop over to 17a.

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darac

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#1109905 17-Aug-2014 13:08

Yes, you're right. I don't know a lot about VDSL, because it's not that commonly used in my country because of really good and well spread fibre and cable infrastructure. I know a lot about ADSL and SHDLS though, but hey concepts are quite similar.

From what I heard from second level support that I talked with few times, and from basic facts, I don't think DLM is enabled all the time. IMO they enable DLM during initial connection (like you said first 10 days) and IF user has problems and complains about them. If you think DLM is enabled all the time please explain this: I had a faulty modem which was causing my DSL to drop up to 15 times a day. Sometimes it worked fine for few days, but mostly it was causing problems on a daily basis. How come that my profile NEVER changed and modem was always synced with about 55-60Mbps? But changing plan from 150 to 500GB just dropped it to 30Mbps. The fact is that my line can definitely handle more than 41Mbps and I can actually see the Chorus cabinet located across the street. When initially installed it synced with 60Mbps and that they have "reset" the port and it synched with 41Mbps. I'm sure that Telecom/Spark is changing profiles to 8b (possibly using custom profiles) for all high usage users (probably not for 500GB plan, but they do it definitely for unlimited users + they limit the throughput during the peek hours). They messed my plan by mistake and changed it to unlimited and presumably that's the reason why I am where I am currently.

I definitely agree with comments from everyone and I know what D stands for and thanks to you I have better understanding of VDSL profiles, but there is definitely some kind of profile manipulation for heavy users by Spark/Chorus present here.

RunningMan

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#1109907 17-Aug-2014 13:20

darac: [snip]
From what I heard from second level support that I talked with few times, and from basic facts, I don't think DLM is enabled all the time. IMO they enable DLM during initial connection (like you said first 10 days) and IF user has problems and complains about them.

It's always enabled, however it is far more aggressive in changing in the first 10 day period and then slows to a far less aggressive rate of change. The idea is to rapidly settle on a good profile when a new connection is activated (first 10 days) and then it will (should) really only change if there is a significant change to the line after that. In the real world, this is usually increased background noise from other new connections coming on line meaning a profile jump that will keep the noise margin at 12.0dB and a resulting lower downstream sync rate for the user.

hio77

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#1109937 17-Aug-2014 14:29

CSRs very commonly state that DLM is only active for the first 10 days, its rather frustrating to read really, considering you assume the CSR knows what they are talking about.

NO isp can influence your profile, apart from resetting your line... if they could, then every man and his cat would be queuing up to jump on the 17a 9db snr profiles, which would be a huge overhead for chorus to manage considering they push DLM on every line.

what spark could be doing is traffic shaping after your physical DSL connection.. although ild expect more people to have complained on gz if this was happening.

your line when it was resyncing alot, probably lost DLM profiles, but not changed bandplans..

it would be very bad for them to be randomly resetting peoples DLM for being "too heavy usage", likely that would surface on here pretty quick and backfire. so ild say that is defiantly not the case here.

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Jase2985

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#1109954 17-Aug-2014 14:58

what was your attenuation when you were connected at 60mbps?

the more people who get VDSL the more those who already have it suffer

hio77

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#1109957 17-Aug-2014 15:01

Jase2985: what was your attenuation when you were connected at 60mbps?

the more people who get VDSL the more those who already have it suffer

6.1 on 8b, so ild say about 8~9 on 17a looking at the first post.

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Talkiet

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#1109963 17-Aug-2014 15:06

darac: Yes, you're right. I don't know a lot about VDSL, because it's not that commonly used in my country because of really good and well spread fibre and cable infrastructure. I know a lot about ADSL and SHDLS though, but hey concepts are quite similar.

From what I heard from second level support that I talked with few times, and from basic facts, I don't think DLM is enabled all the time. IMO they enable DLM during initial connection (like you said first 10 days) and IF user has problems and complains about them. If you think DLM is enabled all the time please explain this: I had a faulty modem which was causing my DSL to drop up to 15 times a day. Sometimes it worked fine for few days, but mostly it was causing problems on a daily basis. How come that my profile NEVER changed and modem was always synced with about 55-60Mbps? But changing plan from 150 to 500GB just dropped it to 30Mbps. The fact is that my line can definitely handle more than 41Mbps and I can actually see the Chorus cabinet located across the street. When initially installed it synced with 60Mbps and that they have "reset" the port and it synched with 41Mbps. I'm sure that Telecom/Spark is changing profiles to 8b (possibly using custom profiles) for all high usage users (probably not for 500GB plan, but they do it definitely for unlimited users + they limit the throughput during the peek hours). They messed my plan by mistake and changed it to unlimited and presumably that's the reason why I am where I am currently.

I definitely agree with comments from everyone and I know what D stands for and thanks to you I have better understanding of VDSL profiles, but there is definitely some kind of profile manipulation for heavy users by Spark/Chorus present here.

You are very wrong on most points.

- Spark doesn't control DLM in any way
- We don't change port profiles for 150 / 500 / unlimited customers because of the above point about not controlling DLM in any way
- We don't own the DSLAMs, so we can't control the DLM in any way.

You are 100% wrong about there being any sort of profile manipulation for heavy users by Spark or Chorus.

Cheers - N

Please note all comments are from my own brain and don't necessarily represent the position or opinions of my employer, previous employers, colleagues, friends or pets.

Jase2985

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#1109965 17-Aug-2014 15:07

"but i have to blame something for me not getting the speed i use to get"

Talkiet

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#1109966 17-Aug-2014 15:09

Jase2985: "but i have to blame something for me not getting the speed i use to get"

BOFH - "Solar Flares"

N :-)

Please note all comments are from my own brain and don't necessarily represent the position or opinions of my employer, previous employers, colleagues, friends or pets.