Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: arunmn73 on September 06, 2020, 03:22:33 PM

Title: FTTC Speed Issue
Post by: arunmn73 on September 06, 2020, 03:22:33 PM
Hi,
I am looking for some advice and guidance re an intermittent issue with my broadband speed. I am with TalkTalk and in a vdsl package with a min download of 10mbps and max of 22mbps. This is because my street is a bit away from the exchange. That said, I have for years got between 18-20 mbps until 2 weeks back when I had intermittent network dropping. Openreach came out and identified a fail and gave me a new line. The speed was fine for a day and the next day it went right down with a latancy of between 70ms and 800ms. I have never seen any latency over 20ms until this issue. Nothing has changed at my end with respect to set up that would cause this. The high latency was obviously affecting my speeds. I have since had 5 OR engineer visits and 2 new routers from TalkTalk. There were a few other issues which OR resolved and they have also done a lift and shift. Whilst my speed from exchange to the house was shown at 22mbps, I was still getting low speeds and high latancy. OR sent an OR fiver engineer who reset my DLM profile and that immediately resolve ld my issue. The OR engineer explained that profile should have reset automatically but in my case it did not which was causing my speed issue even though I was getting the max speed to premesis. The performance was great for 3 days with no issues I.e. low latancy and 20mbps speed. This morning the high latancy and poor speed resurfaced and I am at a loss why that happened. Can anyone please advise what might be causing this and what my options are. I am so frustrated and upset due to this ongoing issue with no end in sight.

Any advice will be greatly appreciated as I know there ta da lot more knowledgeable folks here than me.

Thanks
Title: Re: FTTC Speed Issue
Post by: mofa2020 on September 06, 2020, 03:32:36 PM
Welcome to the forum  :)

Would you post line stats?
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 06, 2020, 04:21:32 PM
Hi,
How do I get the line stats to post?
Title: Re: FTTC Speed Issue
Post by: mofa2020 on September 06, 2020, 04:28:09 PM
From the modem/router user interface. What is the modem/router model?
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 06, 2020, 04:43:51 PM
Itís was the Latest sagemcom TalkTalk WiFi hub but I have changed that to an older TalkTalk d-link DSL-3872 router. The strange thing is that by changing to the d-link router the speed has increased, which I will monitor over next day or so as this has happened before where I have change to this route and speed gets better and then drops. But the latest sagemcom TalkTalk WiFi hub was the one where the speed suddenly dropped from this morning. I donít think itís a router issue whilst readers may see it that way.
Title: Re: FTTC Speed Issue
Post by: mofa2020 on September 06, 2020, 08:12:34 PM
Sorry for the late reply I were on mobile, hoping that the TalkTalk D-link DSL-3872 looks like the DSL-3782 model you might find the same section in the picture just after logging in to router page and clicking on DSL then select the whole section text with mouse cursor and copy/paste in reply here.
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 06, 2020, 08:21:51 PM
Attached, thanks
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 06, 2020, 08:36:33 PM
What I have read in a few forums is this type of intermittent speed issues can be down to a problem with my vdsl profile between openreach and TalkTalk. Could that be the problem? what I donít understand is why my profile would suddenly have an issue when I didnít have any issues before this line fault started two weeks ago. The fact that the reset of my profile by OR engineer immediately fixed the issue makes me wonder that might be accurate, however the fact of the problem resurfaced after three days baffles me.
Title: Re: FTTC Speed Issue
Post by: mofa2020 on September 06, 2020, 08:44:17 PM
Well from the posted picture the line is doing fine in the past 10 hrs, SNRM shows the speed is healthy and DLM is giving all the speed line can handle..

BUT for this part
This is because my street is a bit away from the exchange.

what actually matters is the line distance from FTTC cabinet to your house/building, can you confirm the location of OR cabinet number from BT checker and its approximate distance to you? because at this speed either your line distance is way long to the cabinet or may something else causing the low attainable speed.
Title: Re: FTTC Speed Issue
Post by: mofa2020 on September 06, 2020, 08:52:05 PM
What I have read in a few forums is this type of intermittent speed issues can be down to a problem with my vdsl profile between openreach and TalkTalk. Could that be the problem? what I donít understand is why my profile would suddenly have an issue when I didnít have any issues before this line fault started two weeks ago. The fact that the reset of my profile by OR engineer immediately fixed the issue makes me wonder that might be accurate, however the fact of the problem resurfaced after three days baffles me.

could be that, but other Kitzens would be more helpful in this issue cause I am not from UK and do not have enough knowledge about OR and ISPs profiles.
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 06, 2020, 09:52:34 PM
Well from the posted picture the line is doing fine in the past 10 hrs, SNRM shows the speed is healthy and DLM is giving all the speed line can handle..

BUT for this part
what actually matters is the line distance from FTTC cabinet to your house/building, can you confirm the location of OR cabinet number from BT checker and its approximate distance to you? because at this speed either your line distance is way long to the cabinet or may something else causing the low attainable speed.

Many thanks for all your responses, the distance is around 1.4km so itís a bit away but the key is that I have never has this speed issue in years so not sure why itís started all of a sudden. I agree the line stats show all is well and that is what the OR engineer said as well which is also why I believe itís an issue with my profile (the one that OR engineer reset) to resolve the speed issue in the first place. Hopefully someone might be able to shed some light on possible issue with my profile and if so what, if anything, I can do.
Title: Re: FTTC Speed Issue
Post by: MTW on September 06, 2020, 10:14:11 PM
You say you are getting poor download speed, but what speed are you actually getting?
Title: Re: FTTC Speed Issue
Post by: siofjofj on September 06, 2020, 11:00:12 PM
From your stats it looks like your sync speed is 22Mbps which, as you say, is what TalkTalk predicted so all looks good there. What is your actual throughput speed (i.e. as measured by a speed test website)?

As for the increased latency, it looks like the DLM has applied interleaving to your line (hence the non-zero FEC count) which does increase latency. This does happen when the DLM is reset, but usually is taken off after a few days. Then again, your FEC count seems very high for just 10 hour of uptime. FECs are effectively 'errors that didn't happen', as the interleaving has corrected them, however if interleaving was off these would likely be a large number of CRCs which likely would effect your throughput speed. It looks like the DLM is doing its job here, and keeping interleaving on to keep your line stable. The question is why is this necessary? Can you hear any noise on the line if you use a corded phone plugged into the test socket?
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 07, 2020, 06:48:15 AM
From your stats it looks like your sync speed is 22Mbps which, as you say, is what TalkTalk predicted so all looks good there. What is your actual throughput speed (i.e. as measured by a speed test website)?

As for the increased latency, it looks like the DLM has applied interleaving to your line (hence the non-zero FEC count) which does increase latency. This does happen when the DLM is reset, but usually is taken off after a few days. Then again, your FEC count seems very high for just 10 hour of uptime. FECs are effectively 'errors that didn't happen', as the interleaving has corrected them, however if interleaving was off these would likely be a large number of CRCs which likely would effect your throughput speed. It looks like the DLM is doing its job here, and keeping interleaving on to keep your line stable. The question is why is this necessary? Can you hear any noise on the line if you use a corded phone plugged into the test socket?

Thanks, no I cannot hear any disturbance in the phone line, itís crystal clear. The OR engineer also tested the line with his special phone like device when he rest my profile last week and said there were no errors on voice or data. From what you are saying is this the DLM doing its thing and I just need to ride it out? Yesterday morning when i had my brand new WiFi hub router plugged and which was giving me consistent 20 up and 1 down dropped to 7up and 0.3 down. I did a speed test a few times and speeds  were similar, the latency was sky high. I simply could not use the Internet. as I said above, I swapped to my older dlink router and have since seen the speed increase to 18 up and 0.8 down. This morning the speed has been similar albeit the latency yesterday was around 75ms but this morning itís 36ms (I used to always have latency between 11ms and 20ms which I did see for the 3 days after my profile was rest do believe it was working similar to pre-fault). I am unsure why the issue gets better with a different router as I am pretty sure the other router is not faulty. Itís brand new, I will just monitor the speeds and see how it plays out. You all can see while the sync speed is great my throughput is getting affected. I have never had anything like this ever before, hence I am so confused. Is there any obvious signs of issues that I can challenge TalkTalk?
Title: Re: FTTC Speed Issue
Post by: siofjofj on September 07, 2020, 08:08:36 AM
I'm afraid I don't know anything about the Sagecom device TalkTalk supply (in terms of what chipset it has and whether or not this is any good). What I can tell you is that all lines are slightly different, and on each there can be noticeable differences in performance depending on the modem used, so the fact that the Sagecom device is newer doesn't necessarily mean better. Indeed, one of the favourite modems on this forum, the Zyxel VMG1312-B10A, is getting pretty old now and has long been discontinued. That said, I am surprised there is such a large difference between the two. Are the speed tests done using an Ethernet connection?

Multiple resyncs can also upset the DLM, so try not to change between the routers too many times. My suggestion for the moment is to leave your D-Link device connected and left alone for as long as possible and see if the connection improves further.

I wouldn't say there is anything in particular to report to TalkTalk at this stage.
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 07, 2020, 09:15:20 AM
I'm afraid I don't know anything about the Sagecom device TalkTalk supply (in terms of what chipset it has and whether or not this is any good). What I can tell you is that all lines are slightly different, and on each there can be noticeable differences in performance depending on the modem used, so the fact that the Sagecom device is newer doesn't necessarily mean better. Indeed, one of the favourite modems on this forum, the Zyxel VMG1312-B10A, is getting pretty old now and has long been discontinued. That said, I am surprised there is such a large difference between the two. Are the speed tests done using an Ethernet connection?

Multiple resyncs can also upset the DLM, so try not to change between the routers too many times. My suggestion for the moment is to leave your D-Link device connected and left alone for as long as possible and see if the connection improves further.

I wouldn't say there is anything in particular to report to TalkTalk at this stage.

Many thanks for all your advice. That is exactly what I plan to do, keep on dlink and monitor over next few days.

This is the router I replaced- https://accessories.talktalk.co.uk/productdescription/39

[Moderator edited to merge two posts into one.]
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 08, 2020, 12:30:47 PM
Hi folks. I have been monitoring my speed issue and it was again fine over Sunday and Monday and today again the speed started to feel slow so I did a few speed tests and whilst it rang 18mb down and 0.9mb up, the latency was very highly 270ms. So I went and got the line stats via my dlink router which I have attached. I would be grateful if anyone can shed light on a few things:
Why am I now showing CRC when I did not have any on my last post on Sunday
FEC is showing 0/some large number where on Sunday I had a few FEC
Why is my latency increased suddenly, seems to be changing every 2 days
I also see my uptime is showing 9 hrs. Why is that I changed to this dlink router on Sunday and have not changed or switched it off, so should the up time not be much higher? Is it getting possibly disconnected automatically due to an issue?

Any guidance will be greatly appreciated

Thanks
Title: Re: FTTC Speed Issue
Post by: tiffy on September 08, 2020, 03:07:24 PM
The line stats you are providing from your D-Link router are very limited and as such make it difficult to offer a very definitive opinion on your line condition, have a look at the "DSLStats" web site and you can see the sort of detail that is available from a suitable router, not sure if your particular D-Link router falls into that catagory, basically has to use a Broadcom chip set and have Telnet/BusyBox access.

From the limited stats provided, the best estimation of line length is from DS line attenuation (shown as DownLink on your router) yours is 26.9 dB, that's a long line (house to PCP/fibre cabinet) by VDSL-2 standards, measuring physical distance to the cabinet can be misleading as the cable very often does not take a direct route.
As a close comparison, my line shows a 29.8 dB. DS attenuation and I get very close to 40 Mbps. DS synch and approx. 5.6 Mbps. US synch speeds, so in theory, your line could do better but accepting that every line is unique and every modem/router can behave well or badly on different lines.

Your DS SNRM shows 5.9 dB which would normally indicate that a greater DS synch speed could be achieved but would really need to know if your fibre cabinet was Huawei or ECI and if DS G.Inp was active.

Quote
I also see my uptime is showing 9 hrs. Why is that I changed to this dlink router on Sunday and have not changed or switched it off
Your stats show the "DSL up-time", it's very likely you had a DLM re-synch for some reason, this usually occurs in the early hours of the morning, approx. 01:00 to 04:00 hrs. but can be any time, more detailed router stats would show "router up time" as well so you could tell the difference between a DLM re-synch and a re-boot of the router.

Try to establish if your D-Link router supports more detailed stats provision, there's plenty of good information available on the subject on this forum and on the "Broadband" information section, with more detailed stats there will be a much better chance of diagnosing if your line is performing to it's best capability or you do indeed have an issue.
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 08, 2020, 05:44:28 PM
Many thanks for all your advice, my router is not compatible but I will see what else I can find online. The key thing that baffles me is that I have the same set up for years and have never had this issue but since I got a new D line the latency issue and throughput issues surfaced. I can understand if something has changed from my internal set up but everything is as is.
Title: Re: FTTC Speed Issue
Post by: tiffy on September 08, 2020, 06:17:06 PM
Quote
Many thanks for all your advice, my router is not compatible but I will see what else I can find online.

The old BT issue Huawei HG-612 modem (unlocked) would fit the bill for stats harvesting, they are very cheaply and readily available on line and very easy to unlock, all details available on this forum, you could bridge this to your existing hardware to perform router function I would think so outlay should be modest.
DSLStats will run on Windows, Linux or a Raspberry Pi.
RouterStats will run on Windows or Linux (under Wine)
Both programs are free.

Quote
The key thing that baffles me is that I have the same set up for years and have never had this issue

As with all things in life, it's OK until it's not OK, your D side line swap is likely to be a factor I would have thought, certainly worth further investigation.
Extract, log, record some proper line stats, preferably on a 24/7 basis with "DSLSDtats" or "RouterStats" and advice/analysis will be available here.
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 08, 2020, 06:40:44 PM
The old BT issue Huawei HG-612 modem (unlocked) would fit the bill for stats harvesting, they are very cheaply and readily available on line and very easy to unlock, all details available on this forum, you could bridge this to your existing hardware to perform router function I would think so outlay should be modest.
DSLStats will run on Windows, Linux or a Raspberry Pi.
RouterStats will run on Windows or Linux (under Wine)
Both programs are free.

As with all things in life, it's OK until it's not OK, your D side line swap is likely to be a factor I would have thought, certainly worth further investigation.
Extract, log, record some proper line stats, preferably on a 24/7 basis with "DSLSDtats" or "RouterStats" and advice/analysis will be available here.

Appreciate that but the 6 OR engineers who have been to the house and ran countless test have categorically stayed the line is perfect (even did a lift and shift so say I have a brand new line) and it could be down to an MDF issue with talk talk equipment at the cabinet. I did not even know that ISPs has their own equipment but OR engineer says they do / talk talk, sky and of course BT ate the three that do. Re DSL stats site I went on it but my dlink 3872 model is not on the compatible list 3870 is. I could still try and see if it works. I just donít want to gubb my router by doing something and be left with no internet! This is perhaps my paranoia kicking in as I have now been passed from pillar to post between OR and talk talk.
Title: Re: FTTC Speed Issue
Post by: tiffy on September 08, 2020, 07:27:06 PM
I understand you dilema.

Have you checked RouterStats for modem compatability:
http://vwlowen.co.uk/internet/files.htm

Could likely be the same issue as DSLStats if your modem/router does not use a Broadcom chip set.
There is very much cut down version of RouterStats which works with Lantiq chip sets such as earlier BT Home Hubs, PN Hub One etc., see site, limited stats but better than nothing.

Quote
I did not even know that ISPs has their own equipment but OR engineer says they do
On ADSL2/2+ service (LLU) TT do have their own equipment at most major exchanges.
I don't believe this is the case on VDSL2 (FTTC) service, there is no "other provider" kit in the BTw/OR FTTC (DSLAM) cabinets.
I'am sure I will be corrected on this if untrue !

Quote
my dlink 3872 model is not on the compatible list 3870 is
Give it a try, the program author, roseway (Eric), would be the first to admit that the device compatability list is not completely comprehensive.
Title: Re: FTTC Speed Issue
Post by: burakkucat on September 08, 2020, 07:31:34 PM
On ADSL2/2+ service (LLU) TT do have their own equipment at most major exchanges.
I don't believe this is the case on VDSL2 (FTTC) service, there is no "other provider" kit in the BTw/OR FTTC (DSLAM) cabinets.

For VDSL2 based services, all ISP/CP's equipment is situated in the (fibre) head-end exchange building.
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 18, 2020, 12:44:56 PM
Hi,

I have been trying to get a tool that can capture more details but all the one mentioned here donít work for me, does not allow me to remote into my router. I downloaded a tool called pingplotter to capture pins and pack loss details. I have attached the line stats from my router and a snap of the ping trace to google. As you can see there is packet loss but I cannot figure out what is causing it. When I run a speed test it comes with 19down and 1 up but due to Hugh latancy the speed does not translate into performance. The CRC and FEC are also high. Any suggestions on what I could do as ISP is simply looking at speed test and not doing anything. Thanks in advance.
Title: Re: FTTC Speed Issue
Post by: Chrysalis on September 18, 2020, 01:38:45 PM
I will speculate you on a ECI cabinet, that is just speculation mind.

If I am right then I think whats  happened is the line has too many errors and is getting moved onto a interleaving profile which in turn increases latency, with that FEC count, you not going back to fast path any time soon.

Do you use powerline networking?
Title: Re: FTTC Speed Issue
Post by: arunmn73 on September 18, 2020, 04:21:32 PM
Thanks, Yes I used to use powerline adapter but have removed that and now, any suggestions on what I can do, itís driving me insane! Do you think it could have started since my line change?