Kitz Forum
Broadband Related => ADSL Issues => Topic started by: GigabitEthernet on September 25, 2012, 07:21:27 PM
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I seem to accumulate a massive number of FEC errors on a daily basis. I know these are not issues in themselves, but could it indicate some interference perhaps?
Here are my stats:
Max: Upstream rate = 1040 Kbps, Downstream rate = 8808 Kbps
Path: 0, Upstream rate = 1040 Kbps, Downstream rate = 8174 Kbps
Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 4.4 5.8
Attn(dB): 44.0 22.2
Pwr(dBm): 0.0 12.7Since Link time = 11 hours 16 min 15 sec
FEC: 878980 0
CRC: 112 403
ES: 86 266
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
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Well, yes. Definitely something is causing a problem to the data transfer on your line but, fortunately, the error correcting code is able to salvage the data without needing to request a retransmission of the affected block.
Here are my corresponding statistics --
Max: Upstream rate = 952 Kbps, Downstream rate = 5848 Kbps
Path: 0, Upstream rate = 940 Kbps, Downstream rate = 5820 Kbps
Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 1.5 6.0
Attn(dB): 50.5 28.6
Pwr(dBm): 19.9 12.8
Since Link time = 26 days 7 hours 34 min 25 sec
FEC: 551889657 0
CRC: 846990 1203
ES: 128384 948
SES: 14623 1
UAS: 0 0
LOS: 1 0
LOF: 0 0
You seem to be clocking up FECs at a rate of nearly 1300 per minute, whereas for my line it is a rate of nearly 14564 per minute!
Care to swap lines? :P
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Wow, Mr Cat ..... thats a lot of interleaving going on there, never mind ES !! You look to have issues yourself there bud ??!!
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Wow, Mr Cat ..... thats a lot of interleaving going on there, never mind ES !! You look to have issues yourself there bud ??!!
Thanks for confirming it. Now if you would care to arrange to be seconded to the East Anglia region, with a particular bias towards the EABSE exchange, then I might be inclined to do battle with TalkTalk to arrange for an Openreach technician sheep appointment! :D
With regards to the Huawei HG612's ability to "hang-on" during a "noisy onslaught", I have watched the DS SNRM reach zero, go negative (to -1 dB) and then some more (to -1.9 dB) whilst still providing throughput. It was only when the DS SNRM reached -2.0 dB that the device let go and invoked a re-sync event. I am suitably impressed with the BCM6368 within the device. ;)
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LOL .... the way the floods are going up here, there's half a chance I may end up sailing past E. Anglia in the very near future !! ;D
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So, is there anything I can do?
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In my opinion, probably not. :no: Unless, that is, you have thousands of pounds that you are prepared to give to the BT Group plc. ::)
Are you concerned because of a sudden noticeable effect on your line's performance or is it just because you have the means to observe the statistics? If it is the latter, I would suggest that you do as I do and just ignore the figures. ;)
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So, there is nothing I can do about this noise?
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:hmm: Hmm . . . Assuming that is your QLN graph, you could determine the frequency of each distinct, major peak and then: (1) check to see if it is an authorised broadcast transmission (2) monitor the frequency with some suitable directional apparatus, with the aim of locating its source.
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:hmm: Hmm . . . Assuming that is your QLN graph, you could determine the frequency of each distinct, major peak and then: (1) check to see if it is an authorised broadcast transmission (2) monitor the frequency with some suitable directional apparatus, with the aim of locating its source.
I wouldn't even know how to start?
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I wouldn't even know how to start?
From the beginning, from first principles! ;)
We know that in the UK an xDSL service has tones spaced at 4.3125 kHz.
Thus Tone 0 begins at 0 Hz and extends up to 4.31249999999 . . . kHz. Tone 1 begins at 4.3125 kHz and extends up to the start of Tone 2. Tone 2 starts at 2 x 4.3125 kHz and extends up to the start of Tone 3.
Hence the range of frequencies for Tone N is from (N x 4.3125) to ((N + 1) x 4.3125) kHz.
We now look at an accurate QLN plot and annotate each peak with its closest tone number (or numbers). By substituting for N, in the above, we can calculate the frequency range of the "noise" signal. We can then compare those frequencies against known LW and MW broadcast stations, using the Medium Wave Radio (http://www.mediumwaveradio.com/uk.php) site, for example. If there is no match, then the peak in question could be due to some extraneous event. If that is the case, you will need some form of portable receiver (with a directional aerial system), maps of your locality, a notebook, lots of time and patience.
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Thank you, bk.
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Fec errors are not considered a problem, unless service affecting. I have seen fec errors increment from the dsl out in the exchange.
Crc events or error seconds are a problem, you have some ;) your snr is dipping over time asuming target of 6db for you i would reccomend a router reset every 2 days let the fault develop and when it gets worse report to your cp.
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JT .... it obviously depends on the level of FEC's, and the speed in which they increment. A lazy way of faulting a circuit is to increase the depth of interleaving, thus giving more FEC's. It is IMO, masking a real-life fault condition.
Interleaving is a great way of stabilising a circuit, but both the OP and B*Cat have far too much interleaving taking place on their circuits. :)
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My DS interleaving depth is currently 64. I could ask for this to be lowered, but then surely I would get more CRCs and ES?
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Yes you would. As I said, interleaving depth is only masking the real issue ........ a faulty circuit.
That said, if it is REIN/RFI causing the problem, it tends to manifest itself purely as FEC's on our HHT. So, if you had your Inter Depth lowered to as low as 2 then you wouldn't get massive CRC's/ES's anyway, just plenty of FEC's. To reiterate, that's if it is REIN/RFI.
If you have the ID lowered and CRC's/ES's are prevalent, then the chances are you have a 'normal' circuit fault. Hope this makes sense ??
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My DS interleaving depth is currently 64.
So is mine now, and I don't believe it to be a problem in itself, unless latency is a critical issue for you. In my case the ping response is still less than 30 ms, so it's no issue at all. I don't see any obvious reduction in speed due to the interleaving. But it's true that it may be obscuring an underlying problem.
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That said, if it is REIN/RFI causing the problem, it tends to manifest itself purely as FEC's on our HHT. So, if you had your Inter Depth lowered to as low as 2 then you wouldn't get massive CRC's/ES's anyway, just plenty of FEC's. To reiterate, that's if it is REIN/RFI.
Hang on, with an interleaving depth of 2, surely I wouldn't get any FECs as interleaving would be disabled?
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Sure ?? I was under the impression that any integer other than '0', gave a level of Interleaving to the circuit ?
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An interleaving depth of 1 equals fastpath. Anything over 1 is interleaved.
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Whoops, Eric is indeed correct. My mistake.
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Okay, should I request the interleaving depth to be changed to 2 then?
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I would for monitoring purposes.
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@ AR - can you request a ID of "2" ..?
- are there any noticeable problems? , you could increase your Noise Margin which may help reduce error counts, but of course at cost of sync speed.
the lower the ID the more susceptible you are to errors on the line? in that respect a low ID on a noisy line would not be suggested...
has the noise increase (on QLN graph) just appeared? or has it been there for a while? you could try turning off everything in your house at the wall except router and laptop, reboot the router and see if it persists, if so then its likely that the source of the noise is a neighbour or somewhere else down the line and will be hard to resolve.
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The problem really is that I was expecting more out of this line on ADSL2+, I think this must be related to that. I mean, I have got barely any increase out of ADSL2+, I was hoping for 8.5Mb+, but I can't get there at the moment!
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Here are the stats for tonight:
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 1064 Kbps, Downstream rate = 8288 Kbps
Path: 0, Upstream rate = 1077 Kbps, Downstream rate = 8015 Kbps
Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 3.7 5.3
Attn(dB): 43.5 22.1
Pwr(dBm): 21.5 12.9
ADSL2 framing
Path 0
MSGc: 59 10
B: 124 24
M: 1 8
T: 2 6
R: 10 8
S: 0.4970 5.9007
L: 2173 282
D: 64 4
Counters
Path 0
SF: 646720 590252
SFErr: 34 20
RS: 84073419 2777658
RSCorr: 182427 232
RSUnCorr: 599 0
Path 0
HEC: 455 36
OCD: 0 0
LCD: 0 0
Total Cells: 197493824 26496844
Data Cells: 43802502 1970893
Drop Cells: 0
Bit Errors: 25537 2998
ES: 23 14
SES: 0 0
UAS: 30 30
AS: 10447
Path 0
INP: 1.17 0.45
PER: 16.15 17.70
delay: 7.95 5.90
OR: 32.19 7.23
Bitswap: 6182 0
Total time = 2 hours 54 min 46 sec
FEC: 182427 232
CRC: 34 20
ES: 23 14
SES: 0 0
UAS: 30 30
LOS: 0 0
LOF: 0 0
Latest 15 minutes time = 9 min 46 sec
FEC: 18968 6
CRC: 4 0
ES: 1 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 25626 1
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 2 hours 54 min 46 sec
FEC: 182427 232
CRC: 34 20
ES: 23 14
SES: 0 0
UAS: 30 30
LOS: 0 0
LOF: 0 0
Previous 1 day time = 0 sec
FEC: 0 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Since Link time = 2 hours 54 min 7 sec
FEC: 182427 232
CRC: 34 20
ES: 23 14
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
A lot of FECs but the ES and CRCs aren't too bad.
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Dont have time to type out a full explanation as I have a few family commitments this week... but DMT (adsl) uses several different bearer channels which have different framing modes. Payload frames can contain either the fast channel or interleaved channel or even both depending on how the SP configures it - for example its possible that they could route VOIP over fast channel and other non time essential traffic via the interleaved channel.
Its also possible to send data down the interleaved channel with a depth of 1 -ie just the bitstream - and no forward error correction.
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how do they compare with your previous connection? (ADSL1 was it?)
your already getting more than the average 44db line at 8.2Mb..or are you forcing that by lowering the Noise Margin? if so then yes your FEC count will be higher, the lower the SNRM, the higher the error count. If I put my SNRM down to 3db the RSCorr (FEC) jumps up considerably, right now your FEC accounts for about 0.2% of all your traffic (i think) - I check the RS (all traffic) vs RSCorr (corrected) vs RSUnCorr (uncorrected, these cause CRC's) and roughly work out how much of my traffic is having to be corrected and compare - one thing I would like to know is just how much latency does correcting traffic add, i.e. how much slower are web pages and downloads if more of your traffic is having to be corrected vs un-corrected? - as far as I can tell it must be micro-seconds and why theres not much noticeable difference, only when the traffic cant be corrected and re-transmits occur.
what was your sync rate on ADSL1 (default noise margin)
and what is it on ADSL2+ (if your result above is with reduced noise margin)
some people on the border of where speeds may be better on ADSL2+ are usually better on ADSL1, your adding twice as many frequencies and these are "weaker" than the first 'half' that you use on ADSL1, and sharing the signal across them when noise is present just weakens the signal further, looking at your QLN it would seem that the noise starts around tone 120 and ends around 380, ADSL1 operates up to tone 256 and ADSL2+ extends it up to tone 512 - because the location of the noise in the tones it means that even though your doubling the use of tones in ADSL2+, your also 'roughly' doubling the 'introduced' noise (tones 257-380), but because these tones attenuate more and have a lower SNR than the lower tones of ADSL1 it means they are affected more by the noise resulting in less speed - also if you take a look at your QLN the noise seems slightly worse/stronger from tone 255-350 before lessening, these combined mean the ADSL2+ signal is taking much more of a hit on SNR and usable bits across those tones, this is why your not getting any/much increase from switching.
if you get 'some' increase and you dont notice any slowdown of traffic and web-pages still render at same speeds and dont 'hang' now and again, then it may be worth sticking with it and working on locating the source of the noise. One can get drawn into keep checking their xDSL stats and trying to keep sync high and errors low to the point it becomes obsessive, sometimes Im glad I cant check stats on my Sky Hub because I would be checking them all the time & trying different Noise Margins VS Error Counts etc lol... infact ive just purchased a Huawei HG612 so I can have a BCM6368 chipset with tweakable SNR and stats monitoring...lol
EDIT: I see you have an HG612...great, you can help me unlock it when it comes lol
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Well, on ADSL1 I got 8000Kbps at a 6dB margin (it actually synced at that at 7dB sometimes), here the default margin is 6dB (untweaked) and I get the same.
So, what can I do to see if the noise is in my home?
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Here are the stats for tonight:
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 1064 Kbps, Downstream rate = 8428 Kbps
Path: 0, Upstream rate = 1077 Kbps, Downstream rate = 8015 Kbps
Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 4.3 4.9
Attn(dB): 43.5 22.1
Pwr(dBm): 21.7 12.9
ADSL2 framing
Path 0
MSGc: 59 10
B: 124 24
M: 1 8
T: 2 6
R: 10 8
S: 0.4970 5.9007
L: 2173 282
D: 64 4
Counters
Path 0
SF: 5666515 431938
SFErr: 220 390
RS: 736646719 1836985
RSCorr: 1377312 3150
RSUnCorr: 4425 0
Path 0
HEC: 2717 658
OCD: 0 0
LCD: 0 0
Total Cells: 1730425271 232253809
Data Cells: 61642979 3191555
Drop Cells: 0
Bit Errors: 216615 64342
ES: 129 202
SES: 1 0
UAS: 30 30
AS: 91531
Path 0
INP: 1.17 0.45
PER: 16.15 17.70
delay: 7.95 5.90
OR: 32.19 7.23
Bitswap: 47395 0
Total time = 1 days 1 hours 26 min 10 sec
FEC: 1377312 3150
CRC: 220 390
ES: 129 202
SES: 1 0
UAS: 30 30
LOS: 0 0
LOF: 0 0
Latest 15 minutes time = 11 min 10 sec
FEC: 15033 0
CRC: 5 0
ES: 3 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 2627 57
CRC: 0 6
ES: 0 4
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 1 hours 26 min 10 sec
FEC: 30110 335
CRC: 11 40
ES: 8 23
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 1 day time = 24 hours 0 sec
FEC: 1347202 2815
CRC: 209 350
ES: 121 179
SES: 1 0
UAS: 30 30
LOS: 0 0
LOF: 0 0
Since Link time = 1 days 1 hours 25 min 31 sec
FEC: 1377312 3150
CRC: 220 390
ES: 129 202
SES: 1 0
UAS: 0 0
LOS: 0 0LOF: 0 0
Not looking too good :(.
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is the noise present all the time or is it rising at peak times? have you ran/checked the scripts we have been using?
personally I would run the scripts for 24 hours and look at the SNRM over time and see if its gradually kicking in, see how your Noise Margin drops to 4db as soon as its sync'd at 6db...meaning at that moment in time theres 2db worth of noise on the line...
if it were me I would monitor to see when it happens / or is at its worst and see if I can relate the timing to anything turning on or in use in my house, if not then I would turn every device off in my home (at the wall as standby is no good) except the router and use a laptop in the next room to check stats in the router via wifi - then check the QLN / SNR / SNRM and see if theres any difference, if so then you know its something in your home, turn on each device one by one until the QLN / SNR / SNRM changes then you have found the culprit... if the noise is still present when everything is turned off then its a neighbour or somewhere else down the line and could be hard to sort out.
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Well, from my research, installing an RF3 filter may help things, would this be a good thing to do? I have also discovered that the iPlate has an RF3 filter built in, does the vDSL faceplate have the same?
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iPlate has RF3 built in? does it? hmm - I dont think the SSFP has (VDSL faceplate) - RF3 may be able to remove some noise but it can also remove some of your broadband signal, ive had no personal experience with RF3's this is just what I have been told, you could try it? have you already determined that the noise source is not in your home? , if not it will be worth trying to find that out before purchasing RF3 filter.
edit: an iPlate has a Bell-Wire filter on it (22mH choke which is a low-pass filter), I wonder if this is what your confusing with an RF3 filter (which is something else entirely different) ..?
if you have a filtered faceplate (which you have) then your bell-wire is already filtered (if its even connected, terminal 3)
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My only experience of an RF3 was when an OR engineer experimentally fitted one in the course of diagnosing a problem I had at the time. The effect of the RF3 was to reduce my connection speed by about 20%, so it was quickly removed again.
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edit: an iPlate has a Bell-Wire filter on it (22mH choke which is a low-pass filter), I wonder if this is what your confusing with an RF3 filter (which is something else entirely different) ..?
According to this (http://www.run-it-direct.co.uk/bt-junction-boxes/bt-80b-rf3-available-now-t38.html), it does have an RF3.
Quote added for convenience:
We now have the BT 80B RF3 available to purchase online. These have the same inductor as the BT I Plate so if you installed the following you acheive the exact same result as the I Plate :-
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hmm thats odd - i may be wrong but I think they are two different things.
the Bell-Wire inductor is a 22mH choke that acts like a low-pass filter that wipes most of the xDSL signal from the ring-wire allowing only the phone signal to pass-through, this stops any interference thats in the xDSL part of the spectrum that's getting into the ringwire (which is only in your extension wiring in the home) from back-feeding into the xDSL signal itself, and its only partially/mostly successful... I think anyway.
the RF3 Filter attempts to strip interference from the xDSL signal (that may be introduced anywhere down the line from exchange to nte) without affecting the signal itself..but people have reported that it does so, if the noise is having a massive impact on your broadband then RF3 may remove it but may also take the broadband in that range with it too, but result is stable broadband, albeit with or without lower speed, as Roseway said he had 20% reduction in speed, I believe B'Kat also had one installed.
if you read the iPlate page on his website it says:
How?
- Provide a filtered ‘bell wire’ which reduces the amount of noise picked up by home extension wiring from affecting the broadband ADSL signal.
- Provide common mode filtering of RF signals without affecting frequencies in the ADSL band.
to me this implies it has both a 22mH inductor and RF3...possibly anyway
if you take a look at the pictures of each one, the bell-wire inductor is a small white rounded thing, the RF3 is a bigger black unit with lots of copper wire exposed, looks like they are wrapped around a magnet - the RF3 is slightly larger than the 22mH choke, not saying they cant make smaller one...but...
RF3 filter is usually more for removing noise from your telephone line
Bellwire Inductor is for removing noise from the bellwire in your home
..thats the way I see it anyway
one thing I can tell you is that the SSFP your using does not have RF3, but your faceplate might have 22mH Choke.. the Bell-Wire Inductor is now fitted onto the actual faceplate of newer NTE-5's , SSFP would not have RF3 because its used for a VDSL service and they wouldnt want anything messing with the signal. also if your master socket is the only socket you have then you do not have a bell-wire, and even if you did the SSFP filters the broadband from the phone signal BEFORE passing it on to the extension wiring, thats the whole point of filtered faceplate.
RF3 FILTER ------ 22mH CHOKE on back of NTE-5
(https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fwww.kitz.co.uk%2Fadsl%2Fimages%2Fphone%2FBT80A_RF3.jpg&hash=3234403eea566ba25627590056ff27cdc97ce9ab) (https://forum.kitz.co.uk/proxy.php?request=http%3A%2F%2Fwww.kitz.co.uk%2Fadsl%2Fimages%2Fphone%2FNTE5_faceplate_reverse2007.jpg&hash=2cf64fc9fa5381e120e8fd2de154f47c5434ffbf)
maybe someone else can shed some light on this?
it wont hurt trying an RF3 anyway, at least you can remove it if it has a negative impact.
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I have been doing some maintenance on my master socket (clearing up the wires), and I think the QLN is better. Could somebody confirm?
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yes theres defo improvement, especially up the higher end... what did you do/change exactly?
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yes theres defo improvement, especially up the higher end... what did you do/change exactly?
BT wouldn't like it, but I just cleaned up the wires coming in from outside; I just made sure the wires were straight and there were no creases, then I just reconnected them to the back of the master socket 'plate' and it seems to be better.
I have got an iPlate coming tomorrow to see if that helps. I will probably order an RF3 filter, to see if that helps.
Thanks for your help so far everyone :).
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straight? how was the wiring before? I think it was poor contacts on the faceplate resulting in poorer common-mode noise rejection (noise cancellation in xDSL connection).. now you have cleaned the contacts they are making better contact and creating a slightly cleaner, more 'balanced' signal (and thus better noise rejection)...something like that anyway.
be interesting to see what the i-Plate does for you... because... can you sit that between the SSFP and Backplate? if you replace the SSFP with the i-Plate you will need to use a filter for phone & broadband and your DSL signal will route through to your extension sockets where it can be degraded, of course an i-plate is supposed to resolve that but its not 100% successfull at removing all noise from the bellwire (and if no wire on terminal 3 its a waste of time...well..for the inductor anyway)... a Filtered Faceplate is a much better solution than an i-Plate, unless of course it has an RF3 filter built in and that helps remove noise introduced into the line external to your home.
if your going to use both SSFP and i-Plate I think the i-Plate goes on first then the SSFP (which you will simply be using as a filter)
I would like to find out for sure if an i-Plate has an RF3 in it because everyone knows that RF3 can reduce broadband speed sometimes (if to make the line more stable), and for BT to sell it as a broadband accellerator would be daft when in some/most cases it would degrade speed - the whole point of the i-Plate was to remove noise from the bellwire (which increases speed)...thats it! which it does with the 22mH inductor - everyone used to say that if you removed the bellwire then i-Plate is waste of time...well that wouldnt be true if it had some magical RF3 filter that removes noise with no impact to broadband signal at all...everyone would be using them lol... doesnt add up for me.
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...be interesting to see what the i-Plate does for you... because... can you sit that between the SSFP and Backplate?
This (http://www.skyuser.co.uk/forum/cabling-faceplate-help/44260-suppressing-radio-frequency-interference-intermittent-adsl-disconnects.html#post332573) suggests it is possible.
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how was the wiring before you 'cleaned' it? wasnt running by any electrical wiring was it? (EMI)
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how was the wiring before you 'cleaned' it? wasnt running by any electrical wiring was it? (EMI)
I don't think so. I only made sure the wiring wasn't creased and I put it back in more carefully.
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aye defo sounds like bad contacts..
got your i-Plate yet? my HG612 aint here...was hoping it would be today as was dispatched monday
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Got the iPlate - didn't make any difference :(. I have now ordered an RF3 filter to see if that helps, if not, I will give up as there isn't really anything else I can do.
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be interesting this - if the RF3 knocks out noise OR broadband signal (or both) I think that pretty much proves that the i-Plate has only a 22mH Inductor and not an RF3 filter, otherwise the result would be same.
at least you got some of the noise down, has the speed improved at all since that?
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I got my HG612 - having problems actually getting internet through it...could you help?
I got sync to exchange and IP address from sky...but nothing coming through? i can access router
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...has the speed improved at all since that?
Nope.
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Received the RF3 today and installed it. The SNRM seems to be better and I seem to be syncing faster than I usually would be at this time of day. Attached is a QLN graph with the RF3 installed.
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Ah, ha! That agrees with the data recorded before and after the fitment of an RF3 to my line. :)
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Ah, ha! That agrees with the data recorded before and after the fitment of an RF3 to my line. :)
It's definitely better, but I don't know how much better.
Attached are two QLN plots showing before and after
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Here are the current stats (synced in the evening which explains the lower sync). The SNRM is better, I'm sure:
Status: Showtime
Retrain Reason: 8000
Max: Upstream rate = 1068 Kbps, Downstream rate = 8124 Kbps
Path: 0, Upstream rate = 1072 Kbps, Downstream rate = 7232 Kbps
Link Power State: L0
Mode: ADSL2+
TPS-TC: ATM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 5.5 5.7
Attn(dB): 43.5 22.1
Pwr(dBm): 20.9 12.9
ADSL2 framing
Path 0
MSGc: 59 10
B: 226 24
M: 1 8
T: 1 6
R: 16 6
S: 1.0000 5.9280
L: 1944 278
D: 32 4
Counters
Path 0
SF: 339922 310611
SFErr: 11 80
RS: 22094804 3722539
RSCorr: 5715 461
RSUnCorr: 118 0
Path 0
HEC: 107 90
OCD: 0 0
LCD: 0 0
Total Cells: 94216124 13946701
Data Cells: 1444260 213517
Drop Cells: 0
Bit Errors: 8002 7942
ES: 5 43
SES: 0 0
UAS: 29 29
AS: 5524
Path 0
INP: 1.05 0.34
PER: 16.25 17.78
delay: 8.00 5.92
OR: 32.00 7.19
Bitswap: 2772 0
Total time = 1 hours 32 min 41 sec
FEC: 5715 461
CRC: 11 80
ES: 5 43
SES: 0 0
UAS: 29 29
LOS: 0 0
LOF: 0 0
Latest 15 minutes time = 2 min 41 sec
FEC: 70 0
CRC: 0 0
ES: 0 2
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 1171 265
CRC: 0 40
ES: 0 18
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 1 hours 32 min 41 sec
FEC: 5715 461
CRC: 11 80
ES: 5 43
SES: 0 0
UAS: 29 29
LOS: 0 0
LOF: 0 0
Previous 1 day time = 0 sec
FEC: 0 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Since Link time = 1 hours 32 min 3 sec
FEC: 5715 461
CRC: 11 80
ES: 5 43
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
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It's definitely better, but I don't know how much better.
Attached are two QLN plots showing before and after
I'm not too sure about that.
I thought the further away from zero, the "quieter" the noise (meaning the noise is more highly attenuated).
i.e. the "before" graph looks like a quieter connection.
Also, just for curiosity, are you now using M$ Excel or something similar to graph the stats?
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Also, just for curiosity, are you now using M$ Excel or something similar to graph the stats?
Excel as the scripts don't run on Macs.
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It's definitely better, but I don't know how much better.
Sorry, I was implying that the SNRM was better.
The QLN graph appears to be worse because it is taken at night, rather than in the day like the other one is.
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It's definitely better, but I don't know how much better.
Attached are two QLN plots showing before and after
I'm not too sure about that.
I thought the further away from zero, the "quieter" the noise (meaning the noise is more highly attenuated).
i.e. the "before" graph looks like a quieter connection.
Thanks for typing that, Baldy. I was beginning to think that either I was seeing things or had been on some Black Sheep potion! ::)
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Well, I think I have done everything I can now, and I have barely made any difference. Oh well :(.
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Hello everyone, I am still trying to deal with this 'problem'. Sorry if I am repeating myself, but is there any noise here that could be coming from my own home, or is it mostly RFI?
QLN graph attached.
Thank you,
AR.
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There's not a lot that one could say about that graph. To my inexperienced eye, it looks to be mainly background "mush".
Have you tried with a laptop computer and the Huawei HG612 both running from a 12 V car battery, whilst the rest of the house is switched off at the main isolator? :-\
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Have you tried with a laptop computer and the Huawei HG612 both running from a 12 V car battery, whilst the rest of the house is switched off at the main isolator? :-\
No I haven't. How would I go about doing that - sorry if that sounds stupid.
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No I haven't. How would I go about doing that - sorry if that sounds stupid.
Why, no, it doesn't sound stupid. Not everyone has an inventive sort of mind.
Going back to your question "is there any noise here that could be coming from my own home, or is it mostly RFI?", the only way to answer it is by performing the experiment of "turning off" your home. So that is the first step -- use the main switch at your consumer unit so that everything is off.
Second step is the consideration of powering a computer. Assuming you own or can borrow a laptop system, with its battery fully charged, then that can be ticked off.
The third step is a little more difficult. You will need a power source for the HG612. So borrow a 12 V car battery. Hunt around for an old defective PSU from a modem/router whose plug will fit into the HG612's socket. Cut off the plug and wire (putting the old PSU out for electrical/electronics recycling). Ensure that you connect the wires to the car battery the "right way round" so the the outer connection at the plug is the negative and the central receptacle is positive. Connect up the HG612 and make your measurements.
:)
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.............. and purchase a flipping long DSL lead, to reach from the VDSL/ADSL filter to your new 'study'. ;) ;D
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I can see that Black Sheep dost jest -- but for those who do not see, when I say borrow a car battery I intend for the battery to be removed from the car and carried indoors! ::)
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:lol:
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:lol: :lol: :).
Thank you everyone for your help.
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FEC errors can be caused by many different things, line faults, RF interference, rein, crosstalk and of course the profile your service provider or in the case of BT, DLM decides to assign. One of the things not mentioned in this forum yet is cross talk, cross talk is the transfer of unwanted signal energy from one circuit to another, adsl and other digital circuits give off a lot more cross talk (or transferred signal energy) than analogue services such as POTS (plain old telephony service). Now that more and more people are signing up for adsl then the crosstalk in Openreach cables is increasing like you wouldn't believe, this is not deemed as a fault! . I have seen circuits synching at 12meg eventually run down to 7.5meg, what was the fault? there was no fault! just that the available signal received at the router was being partially swamped by somebody else's adsl signal. Basically if you are the only digital circuit in a 20 pair cable feeding a block of flats then HOORAH you should be ok, but when the other 19 flats get converted to adsl then you WILL be affected, your SNR will drop and FEC errors will increase as your router tries to determine between the signals it receives!
don't worry when FTTP(fibre to the premises) arrives there will be no more attenuation, no more rein, no more noise and no more crosstalk!
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Strangely, some of the interference seems to have disappeared today. Attached is a QLN graph showing the improvement.
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Just a quick note here, if you look toward the bottom of this page:
http://www.kitz.co.uk/adsl/btsockets.htm
Look at the RF2 and RF3
The rf 2 is installed to try and filter out any noise outside that of the intended phone conversation.
This could be radio interference such as local/national radio, taxi ranks, offshore comm's etc
Then along came DSL. problem is the filter adds about 43db loss to the dsl signal so the RF2 either severly slows down your connection. Or if you're about 2.7km or futher on a 0.5 copper line from the exchange , no sync at all (unless theres corrosion in the rf2 then some dsl can slip through)
The RF3 was brought out to do the same job as the RF2 over the voice frequencies, but allowing the DSL signal to go through.
The small black cylindrical attenuators of which you see 2 off in the RF2 is the nearly same component in the newer faceplates, just the one on the bell wire. It utilises the problem it caused on either leg for letting a dsl signal get through to obscuring most noise picked up by the bell wire from being heard by the DSL signal.
:graduate: