Kitz Forum
Broadband Related => FTTC and FTTP Issues => Topic started by: michty_me on April 02, 2015, 09:51:50 AM
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Good morning everyone!
Long time lurker but barely made any posts here.
I'm looking for information as to why I am suffering drop outs on my line.
My fibre connection initially synced at 75Mb and was running this for a few months but after trying home plugs my sync went down to 48Mb in two days. They were removed and sent back. Within a few weeks, My sync had recovered to 64Mb and Zen confirmed a cap was still on the line. They suggested waiting a few more weeks. Today however, My ECI modem re-synced at 60.1Mb and pings increased to 40ms approx.
I discovered I am on a Huawei 288 cab so I took the opportunity to connect my unlocked HG612 as I thought matching modem and cab may help. Whilst I was changing the modem out, I left it powered off for an hour and made a slight adjustment to my internal wiring. (I found the second incoming pair had at least four extensions joined into it for some reason and was also wired into the master socket? All extensions are disconnected now so all that leaves is the incomer.
These are the stats I pulled from the modem earlier using DSLstats.
Max: Upstream rate = 27953 Kbps, Downstream rate = 78092 Kbps
Path: 0, Upstream rate = 19998 Kbps, Downstream rate = 64986 Kbps
Line attenuation (dB): 0.0 0.0
Signal attenuation (dB): Not monitored
Connection speed (kbps): 64986 19998
SNR margin (dB): 6.1, 7.0
Power (dBm): 13.6, 7.4
Interleave depth: 1363, 607
INP: 3.00, 4.00
G.INP: Not enabled
EDIT to add:
Per second Per minute Per hour Per day
CRC Up 0 0 0 0
Down 0 0 0 0
FEC Up 0 0.02 0.92 22.1
Down 0.14 8.14 488 11715
HEC Up 0 0 0 0
Down 0 0 0 0
ES Up 0 0 0 0
Down 0 0.13 7.57 182
SES Up 0 0 0 0
Down 0 0 0 0
What do the different levels of INP mean? What do the numbers correspond to for the interleave depth? My IP profile has increased by changing to the Huawei modem anyway by at least 3Mb.
On a side note, I tried to get the HG612 stats GUI to work but couldn't. I may have an old firmware on the modem though as I first 'hacked' it early last year. I updated the HG612 stats program but everything just shows blank. At the moment I don't want to disconnect my line again until I see some positive movement from DLM. I followed the instruction provided but I still couldn't get any stats. I'll try find the latest firmware and flash that when I get a chance.
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I can't comment on your (frequent?) disconnections but I had a similar BDCM > ECI setup and came home one day to find 10ms ping had turned into 25ms. I was on a 40:20 service so noticed no throughput degradation. When I slapped the HG612 on the line, my line stats looked a lot like the ones you just posted (INP and interleaving whacked up with no appreciable error stats - I actually had double digit FECs as I recall).
My conclusion was that the cab just got G.INP'd. There are similar anecdotes across other forums.
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Thanks. I'll keep monitoring my line and see what happens. There has been a lot of work going on near by my neighbours property with all sorts of power tools so I was wondering if something like that had caused noise on the line. What about the 11,000+ FEC errors in 24hrs I posted? Will that have any detrimental effect? I was doing some heavy downloading yesterday after my re-sync. Absolutely no CRC errors though.
I hope to see some positive changes to DLM over the next few days.
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11k FECs is not to be sniffed at I guess!
Some argue that INP 4 and >1k interleave is pretty heavy handed for a one off noise burst but who knows the reasons for getting smited by DLM? :D
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I think it may be because my line was still recovering after using the home plug adapters. I'll leave it be for now and see how we get on in a few days/weeks. ;D
Also spoke with Ixel on here on another forum and he explained a lot so it has helped my understanding.
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What do the different levels of INP mean? What do the numbers correspond to for the interleave depth? My IP profile has increased by changing to the Huawei modem anyway by at least 3Mb.
INP values tell the modem how much protection against Impulse Noise is required; it is measured in the number of symbols (a symbol lasts one four-thousandth of a second, and has a variable number of bits: if tone 1603 has bit-loading of 7, then 1 symbol is 7 bits. An INP of 3 would want protection for 21 bits, on that tone anyway.
In pre-G.INP days, a value of 3 was "low" interleaving, and a value of "4" was high interleaving; recently, however, a greater variety of values has been seen (and G.INP activation comes with values > 40). You would tend to see depths of 1,000 or more.
The other parameter that matters is "delay", which indicates how many milliseconds of additional latency are allowed to be used. delays of 8ms and 16ms are common; if DLM has intervened on both upstream and downstream, then the delays are accumulative.
In pre-G.INP configurations, the modem would respond by making use of FEC (to correct any errors) and interleaving (to spread data around, so that noise bursts affect different blocks of data. With G.INP in place, expect to see FEC and interleaving still in use, but the overheads they employ are considerable reduced (depths less than 64, delays less than 1ms)
I'll try find the latest firmware and flash that when I get a chance.
It is probably worth using B030SP08, which works with G.INP.
Anything earlier than B030 seems to not like G.INP - and can end up with slower speeds and even higher latencies.
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INP values tell the modem how much protection against Impulse Noise is required; it is measured in the number of symbols (a symbol lasts one four-thousandth of a second, and has a variable number of bits: if tone 1603 has bit-loading of 7, then 1 symbol is 7 bits. An INP of 3 would want protection for 21 bits, on that tone anyway.
In pre-G.INP days, a value of 3 was "low" interleaving, and a value of "4" was high interleaving; recently, however, a greater variety of values has been seen (and G.INP activation comes with values > 40). You would tend to see depths of 1,000 or more.
The other parameter that matters is "delay", which indicates how many milliseconds of additional latency are allowed to be used. delays of 8ms and 16ms are common; if DLM has intervened on both upstream and downstream, then the delays are accumulative.
In pre-G.INP configurations, the modem would respond by making use of FEC (to correct any errors) and interleaving (to spread data around, so that noise bursts affect different blocks of data. With G.INP in place, expect to see FEC and interleaving still in use, but the overheads they employ are considerable reduced (depths less than 64, delays less than 1ms)
It is probably worth using B030SP08, which works with G.INP.
Anything earlier than B030 seems to not like G.INP - and can end up with slower speeds and even higher latencies.
Thank you for taking the time to write that. I think I understand most of it. I've just downloaded those very firmwares this minute but will flash it tomorrow at a better time.
Sorry for asking a stupid question but what is the core differences in Original, Unlocked and Webgui? I did have a look through the 9 pages of the HG612 firmware thread but couldn't see what I was really looking for. I think I'm currently on the 28SP10 version.
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I think the unlocked version lets you connect via LAN2, but only has the telnet port working - so you have to connect yourself, and issue commands to extract the stats (or use one of teh stats-harvesting programs). WebGUI adds to unlocked, by also allowing you to point a browser at the LAN2 port, and get the stats via the browser. I tend to not trust the stats given out this way.
Original locks it all back down again.
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Many thanks. Can the unlocked and webgui ones both be read with dslstats or HG612 stats?
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My HG612 allowed access to DSLStats on telnet via lan2, and I could also use the web gui via lan2 as well, this was using it in bridge mode to my router. I had not used the HG612 as a router for some time and only then when I was on ADSL2+. Have not used the HG612Stats program.
Stuart
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I'll try the webgui one first then. Thanks.
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What do the different levels of INP mean? What do the numbers correspond to for the interleave depth? My IP profile has increased by changing to the Huawei modem anyway by at least 3Mb.
INP values tell the modem how much protection against Impulse Noise is required; it is measured in the number of symbols (a symbol lasts one four-thousandth of a second, and has a variable number of bits: if tone 1603 has bit-loading of 7, then 1 symbol is 7 bits. An INP of 3 would want protection for 21 bits, on that tone anyway.
In pre-G.INP days, a value of 3 was "low" interleaving, and a value of "4" was high interleaving; recently, however, a greater variety of values has been seen (and G.INP activation comes with values > 40). You would tend to see depths of 1,000 or more.
The other parameter that matters is "delay", which indicates how many milliseconds of additional latency are allowed to be used. delays of 8ms and 16ms are common; if DLM has intervened on both upstream and downstream, then the delays are accumulative.
In pre-G.INP configurations, the modem would respond by making use of FEC (to correct any errors) and interleaving (to spread data around, so that noise bursts affect different blocks of data. With G.INP in place, expect to see FEC and interleaving still in use, but the overheads they employ are considerable reduced (depths less than 64, delays less than 1ms)
That is some brilliant info, thanks! :D
Question for you... is an interleave depth of one truly akin to fastpath or is it marginally more latent?
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Ok.
I'm all updated and powered the modem back up after 45mins to an hour. New stats are as follows.
Max: Upstream rate = 28386 Kbps, Downstream rate = 78204 Kbps
Bearer: 0, Upstream rate = 20000 Kbps, Downstream rate = 66999 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Downstream Upstream
Line attenuation (dB): 17.2 0.0
Signal attenuation (dB): Not monitored
Connection speed (kbps): 66999 20000
SNR margin (dB): 9.3 11.3
Power (dBm): 13.5 7.4
Interleave depth: 16 8
INP: 49.00 47.00
G.INP: Enabled
My pings have reduced back down to 25ms which is the best it has been. It normally sat around 28ms to BBC.
I wonder if I will get any further speed increases hopefully back to where I started with all my issues in January where I was synching around 75Mb.
Considering my line profile went to 60.1Mb with the ECI modem two days ago, I'm impressed so far that I've gained 6Mb in two days.
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Hey michty that still doesn't look right.
What fw you using with the HUAWEI ?
its being reported that the following firmware's
B027SP06 or v27.06
B028SP10 or v28.10
B030SP06 or v30.06
Will not work correctly with G.INP.
Only one that works is B030SP08 or v30.08
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Hey michty that still doesn't look right.
What fw you using with the HUAWEI ?
its being reported that the following firmware's
B027SP06 or v27.06
B028SP10 or v28.10
B030SP06 or v30.06
Will not work correctly with G.INP.
Only one that works is B030SP08 or v30.08
Hi,
I'm using the latest B030SP08 Webgui version. Just flashed this morning and a brief stats page taken from DSL stats.
What looks wrong with it? I believe I still have a cap on my line which Zen confirmed last week. They have asked me to keep it stable for the next few weeks to see if it lifts. If not they will try and get a DLM reset.
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Ok.
I'm all updated and powered the modem back up after 45mins to an hour. New stats are as follows.
Max: Upstream rate = 28386 Kbps, Downstream rate = 78204 Kbps
Bearer: 0, Upstream rate = 20000 Kbps, Downstream rate = 66999 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Downstream Upstream
Line attenuation (dB): 17.2 0.0
Signal attenuation (dB): Not monitored
Connection speed (kbps): 66999 20000
SNR margin (dB): 9.3 11.3
Power (dBm): 13.5 7.4
Interleave depth: 16 8
INP: 49.00 47.00
G.INP: Enabled
My pings have reduced back down to 25ms which is the best it has been. It normally sat around 28ms to BBC.
I wonder if I will get any further speed increases hopefully back to where I started with all my issues in January where I was synching around 75Mb.
Considering my line profile went to 60.1Mb with the ECI modem two days ago, I'm impressed so far that I've gained 6Mb in two days.
OK - you definitely have G.INP running now - those INP values above 40 are a big giveaway.
Given the change you've seen, it suggests that the very recent slowdown was probably caused by your modem not being compatible with G.INP.
Aside: I know that BT engineers have been told that ECI modems, with old firmware, will not sync at all. However, we're seeing more cases like yours - with noticeable slowdowns and big increases in latency - that happen to both Huawei and ECI modems. We know the Huawei modems that end up like this seem to be on old firmware, but we can't tell about the (locked) ECI's. I wonder if this is new behaviour from BT, as yet unreported via engineers, so that modems at least keep some form of connection up.
Your status now suggests you are syncing at the top of one of the DLM bands (I guess 67Mbps), as you have some SNR margin to spare. That 3dB of SNR would normally be worth another 11Mbps or so - which ties in with the modem's own estimate of an attainable 78Mbps.
Zen's suggestion seems fair enough for now.
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Question for you... is an interleave depth of one truly akin to fastpath or is it marginally more latent?
No different.
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OK - you definitely have G.INP running now - those INP values above 40 are a big giveaway.
Given the change you've seen, it suggests that the very recent slowdown was probably caused by your modem not being compatible with G.INP.
Aside: I know that BT engineers have been told that ECI modems, with old firmware, will not sync at all. However, we're seeing more cases like yours - with noticeable slowdowns and big increases in latency - that happen to both Huawei and ECI modems. We know the Huawei modems that end up like this seem to be on old firmware, but we can't tell about the (locked) ECI's. I wonder if this is new behaviour from BT, as yet unreported via engineers, so that modems at least keep some form of connection up.
Your status now suggests you are syncing at the top of one of the DLM bands (I guess 67Mbps), as you have some SNR margin to spare. That 3dB of SNR would normally be worth another 11Mbps or so - which ties in with the modem's own estimate of an attainable 78Mbps.
Zen's suggestion seems fair enough for now.
Oh right. That is very interesting! I have two ECI modems and this HG612 modem. I may get rid of the ECI modems and purchase a second HG612. I just thought I would try it as my cab is Huawei (match cab and modem).
It seems to have had a positive increase rather rapidly so I'm hoping that it will bring me up to full speed soon. Although my pings have always remained this level since install. That must mean I had a slight interleave on. When was G.INP roll out started?
I've been trying to get my sync speed up since the initial error from the homeplug use back around the 10th of February. I was going to wait the 8 weeks before speaking to Zen again but now I'm seeing a good result for once.
You are correct in saying about the DLM syncing. Zen confirmed my sync rate was 67Mbps.
Out of interest, A friend of mine was trying to upgrade his 40/10 service from BT to the 80/20 service. As soon as it went live it couldn't hold sync and speed was all over the place from 50Mbps to 1Mbps. BT couldn't get to the bottom of it and just put him back on the 40/10 service. I wonder what modem he was using. I must find out.