Kitz Forum
Broadband Related => FTTC and FTTP Issues => Topic started by: jeffers on April 23, 2015, 08:47:27 PM
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Hello all!
FTTC has been enabled about a month ago for my cab (i was the first on it), and theres about 250m of cable between my house and the cab (~130m as the crow flies) so I think I should be getting pretty close to the full 80Mbit. On the initial install date the BTO engineer also said I should get the full 80. Anyway, due to some issues with PlusNet I ended up rebooting my plusnet router a load of times (but not the original ECI Openreach modem) for the first day or so of being live. I hope this wouldnt have caused DLM or anything to kick in. When PlusNet fixed my account my first speedtests looked fine - 72Mbit pretty consistently. Shortly afterwards my speeds dropped and have settled around the 65Mbit mark...
http://www.speedtest.net/results.php?sh=351f211f4b6ab6803c5bead4746a12ac&ria=0
I've finally replaced the original ECI modem and hooked up an unlocked HG612. Without knowing much about FTTC yet, I can see that my max attainable speed is pretty much my current sync speed...
# xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 23897 Kbps, Downstream rate = 64616 Kbps
Bearer: 0, Upstream rate = 18999 Kbps, Downstream rate = 66237 Kbps
Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode(0x0)
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 5.8 9.0
Attn(dB): 18.3 0.0
Pwr(dBm): 13.4 6.7
VDSL2 framing
Bearer 0
MSGc: 18 137
B: 239 236
M: 1 1
T: 23 6
R: 0 16
S: 0.1153 0.3974
L: 16648 5134
D: 1 1
I: 240 255
N: 240 255
Counters
Bearer 0
OHF: 3068797 935059
OHFErr: 90 0
RS: 0 1565223
RSCorr: 0 1
RSUnCorr: 0 0
Bearer 0
HEC: 100 0
OCD: 5 0
LCD: 5 0
Total Cells: 780245879 0
Data Cells: 7686592 0
Drop Cells: 0
Bit Errors: 0 0
ES: 43 133
SES: 0 3
UAS: 27 240522
AS: 6130
Bearer 0
INP: 0.00 0.00
INPRein: 0.00 0.00
delay: 0 0
PER: 1.99 6.58
OR: 96.13 173.80
AgR: 66332.88 19172.57
Bitswap: 4860/4861 6/7
Total time = 1 hours 42 min 37 sec
FEC: 0 1
CRC: 90 0
ES: 43 133
SES: 0 3
UAS: 27 240522
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 15 minutes time = 12 min 37 sec
FEC: 0 0
CRC: 5 0
ES: 4 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 0 0
CRC: 24 0
ES: 9 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 1 day time = 1 hours 42 min 37 sec
FEC: 0 1
CRC: 90 0
ES: 43 133
SES: 0 3
UAS: 27 240522
LOS: 0 0
LOF: 0 0
LOM: 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
LOM: 0 0
Since Link time = 1 hours 42 min 9 sec
FEC: 0 1
CRC: 90 0
ES: 43 133
SES: 0 3
UAS: 0 240495
LOS: 0 0
LOF: 0 0
LOM: 0 0
My internal wiring is fairly minimal and I dont hear any noise on my line.
Have I just got unrealistic expectations or is there likely a problem somewhere?
Thanks
Jeffers
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Which firmware is on that HG612 ?
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Which firmware is on that HG612 ?
Oops, forgot about that..
# equipcmd swversion display
software version: V100R001C01B030SP08
xdsl firmware version: A2pv6C038m.d24j
cpu version: BCM6368
cfe version: 1.0.37-102.6
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The attenuation looks a bit high for a 250m line. My line is about that length and I have attenuation of around 11db. The stats seem consistent with a longer line - do you think that's possible?
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I'd say one issue is the lack of G.INP. Are you connected to a Huawei cab?
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I'd say one issue is the lack of G.INP. Are you connected to a Huawei cab?
No idea. I'll have to take a walk down and snap a picture of it. Unless I can get it out of the modem stats?
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Telnet command xdslcmd info --vendor will confirm one way or the other.
The very soon to be released update to HG612 Modem Stats will also display that detail as per the attachment.
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Telnet command xdslcmd info --vendor will confirm one way or the other.
The very soon to be released update to HG612 Modem Stats will also display that detail as per the attachment.
# xdslcmd info --vendor
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 23811 Kbps, Downstream rate = 63000 Kbps
Bearer: 0, Upstream rate = 18999 Kbps, Downstream rate = 66237 Kbps
ChipSet Vendor Id: IFTN:0xd086
ChipSet VersionNumber: 0xd086
ChipSet SerialNumber:
I've also just started sending data to mdslstats (same username)
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So that's an ECI cab
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So that's an ECI cab
And would explain the ECI modem the BTO guy gave me. There doesnt seem to be any noticeable speed differences between the ECI and the HG612
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Telnet command xdslcmd info --vendor will confirm one way or the other.
More correctly, that command will disclose the line-card's chipset and that, in turn, allows one to establish the type of DSLAM. :)
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The attenuation looks a bit high for a 250m line. My line is about that length and I have attenuation of around 11db. The stats seem consistent with a longer line - do you think that's possible?
I agree with this.
My last line was about 350-400m, and the HG612 reported attenuation of 16.9dB; your attenuation is slightly higher - so you either have a longer line, or a thinner one, or both.
I've attached the stats from last year, when the cab had been standing for over 3 years. Attainable speeds had dropped around 12Mbps over the 2 years we had that service.
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Thanks for the info. I have followed the poles and measured on google maps - its actually less than 250m, something around 215m. Obviously this doesn't include the additional wiring inside the cabs but it should be fairly accurate, and nowhere near the 400m+ mark expected for this level of attenuation.
Prior to FTTC, I was on ADSL2+ and and did all I could to improve the line performance, including replacing all internal wiring which may or may not have included a new NTE5 :police:. The speeds I was getting were pretty good considering my distance from the exchange. Does anything else affect the attenuation? Dodgy filter from the BTO engineer maybe? Whilst 65Mbit is a huge improvement over my old connection I want to make sure I'm getting the most out of it.
My stats have been uploading to mydslwebstats since last night (user jeffers) if anyone is willing to take a look. I did notice a resync this morning to a slightly higher speed but nothing significant.
All help appreciated!
Jeffers
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From looking at your stats, I would guess there is a fault somewhere. You had a large burst of CRC errors at 9:21am which led to a resync, and generally speaking your SNRM is moving around a lot. It is possible, I believe, for an HR type fault to cause an increase in apparent attenuation.
Did anything happen at 9:21 this morning that could have caused the errors? Maybe a phone call?
Could you let us know how your internal wiring is arranged? I don't want to come over all call centre, but does plugging the modem into the test socket on the master help at all?
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From looking at your stats, I would guess there is a fault somewhere. You had a large burst of CRC errors at 9:21am which led to a resync, and generally speaking your SNRM is moving around a lot. It is possible, I believe, for an HR type fault to cause an increase in apparent attenuation.
Did anything happen at 9:21 this morning that could have caused the errors? Maybe a phone call?
Could you let us know how your internal wiring is arranged? I don't want to come over all call centre, but does plugging the modem into the test socket on the master help at all?
I was at work, I just text my wife to see if she used the phone or anything... BUT, I just rang 1471 to see if I had any missed calls. And my connection dropped (about19:05)! The BTO guy fitted a new face thing to my NTE5, I'm guessing thats a glorified filter? Can I just pull it off to get to the master socket?
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Answering my own question here. I have connected a standard DSL filter to the test socket and removed everything else from the line. Attenuation has dropped from 18.4 to 18.1. So its not the filter or internal wiring :( Also using the phone doesnt seem to reliably cause a disconnection.
Any other ideas? I'm guessing the chances of Plusnet/BT accepting this as a fault are slim to none?
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Hmm . . . I think you are going to have to wait and watch, keeping a note of any significant events. I can't see any ISP/CP requesting Openreach intervention on the scant information that the reported attenuation does not seem to agree with the approximate estimated distance of the D-side circuit.
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I think if you tell Plusnet that your speed has dropped, and that using the telephone causes your connection to drop, they will take it seriously. Worst case is they tell you to monitor it for a while.
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I think I'll keep an eye on it for a bit and see what happens. Thanks for the help everyone!
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Thanks for the info. I have followed the poles and measured on google maps - its actually less than 250m, something around 215m. Obviously this doesn't include the additional wiring inside the cabs but it should be fairly accurate, and nowhere near the 400m+ mark expected for this level of attenuation.
Is your line carried by poles all the way to your home (ie your line runs pole -> pole -> pole), so you can follow the actual path? Or is the distribution cable underground, only coming out for each pole to do just the last drop to the homes?
If the latter, then the line could go down one side of the street, feeding poles on that side, before crossing and coming back up the street, feeding those poles. If that were the case, you'd probably see the changes in the estimations for different houses following the street layout.
Anything else, and the problem is more likely to be gauge or material. 0.4mm copper has resistance of around 133 ohms/km, compared to 85 ohms/km for 0.5mm copper; a line of 0.4mm copper would be getting behaviour approaching 1/2 or 2/3 of our normal expectations. Aluminium lines put a similar kybosh on reality over expectation.
Anyway, this is by-the-by while there is a fault around. Dropping broadband by picking up the handset is definitely indicative of a problem...
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A few things.
Often line routing isnt direct.
Basically as far as I know the routing from my cab crosses the road (opposite side to me) then it has to traverse 4 side streets en route, and then cross the road again back to me. Direct its under 200m, actual distance is close to 400m. So thats an example. Its even worse for those nearer the cab but on my side of the road, they get less than 40mbit sync even tho the cabinet is across the road from them as they at the end of the loop.
Next thing to consider what is the estimated line speed at sign up and estimated line speed now (reported on GEA test).
In short if the GEA test passes you will struggle to get a resolution, you might be able to get an engineer sent out with the threat of a charge, but if the engineer's JDSU test passes alongside a passed GEA test then nothing will probably be done.
If your line speed is above the estimate, equal or only a bit below your estimate and both test's pass its probably a case of tough luck.
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As Chrys has stated .......... if the statutory tests pass, and the dropping of connection with handset lifted cannot be simulated ...... then there's really not much that can be done ??
As I've said many times, fault conditions do not mend themselves*, they will progressively get worse which is a pita for you, but a god-send for the engineer.
*A situation can occur where multiple EU's are reporting faulty circuits, and it will likely be a common joint that 'feeds' all the EU's that has been subject to corrosion. By 'remaking' this joint, all circuits will be back to rude health and the unassuming EU's are under the impression the fault has repaired itself. Hope this makes sense ?.
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I am tired, sorry I didnt pick up on the handset symptons.
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Apologies for the possible irrelevance of this post. Is the straight distance between poles going to be accurate for cable length; won't there be slack to consider, and what %?
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It is incalculable, I'm afraid Ren. It's certainly a salient point but there is no way t0 calculate or second-guess the amount of slack in each UG chamber or on overhead carrier poles.
I remember roughly 15yrs ago, myself and a colleague spent days trying to locate a fault in a field. Dig after dig after dig, finally revealed a coil of 20pr armoured cable that would have bought a holiday home if weighed in at the scrapyard ?? The contractors who mole-ploughed it in obviously didn't have a hacksaw to cut it to the required length and just buried it. Played havoc with our meter-readings.
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Point taken! ;) The thing is would it be reasonable with overhead lines to allow ~15%, which would happen to be the difference of 250 and 215m as in the OP's case?
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Bringing this back from the dead somewhat but it looks like things have gotten worse over the last week or so. The VDSL dropped ~6 times over the last 24hrs, sometimes when the phone rings but otherwise fairly randomly. I've raised a voice fault with Plusnet as there can occasionally be noise on the line and a BT guy is due at the end of next week.
In the meantime can someone tell me if its normal for the snrm to change for the duration of a phone call? It doesnt sound right to me. If someone is able to take a quick peek at my stats on MDWS it would be very much appreciated. I had a short (1 min) phonecall at 18:06 today which didnt cause a DSL resync but did cause a change in snrm. The last time i know for sure a call caused a resync was on 7 may at 16:47
Thanks for the help
Jeff
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In the meantime can someone tell me if its normal for the snrm to change for the duration of a phone call?
Thanks for the help
Jeff
It quite common when there is a slight HR fault to see the SNRM dip with higher CRC's when the telephone rings but it should go back to normal during the conversation duration.
Lets hope the Telecom Engineer finds a noticable fault next week
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Minor update, the BTO guys turned up today and heard the noise on the line under certain conditions (seems to be just after an inbound call). Theyve redone the joint on the pole but say another team have to get involved (UG team?) to fix a possible HR fault elsewhere in the circuit. Hopefully over the weekend or Tuesday.
Interestingly, I also asked the guy about the line length to the cab and he said its showing up as 360m. My downstream attenuation is still 18.1 which would either suggest a longer line or some crappy cable in between. Am I right in assuming the HR fault would also increase the attenuation? I'm hoping when they fix the HR fault the attenuation will drop.
The guy has kept the case open until the HR fault has been cleared, once the case closes will BT automatically reset the ine profile or is this something I need to ask about. Bear in mind that it has been raised as a voice fault due to the noise on the line.
Thanks all
Jeff
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Minor update, the BTO guys turned up today and heard the noise on the line under certain conditions (seems to be just after an inbound call). Theyve redone the joint on the pole but say another team have to get involved (UG team?) to fix a possible HR fault elsewhere in the circuit. Hopefully over the weekend or Tuesday.
Interestingly, I also asked the guy about the line length to the cab and he said its showing up as 360m. My downstream attenuation is still 18.1 which would either suggest a longer line or some crappy cable in between. Am I right in assuming the HR fault would also increase the attenuation? I'm hoping when they fix the HR fault the attenuation will drop.
The guy has kept the case open until the HR fault has been cleared, once the case closes will BT automatically reset the ine profile or is this something I need to ask about. Bear in mind that it has been raised as a voice fault due to the noise on the line.
Thanks all
Jeff
Yes, a HR would manifest itself on the router as a higher-than-usual attenuation. Experience shows me that a HR will fluctuate, and as such your attenuation should ??
No, the circuit will probably not be reset if it's a voice fault ...... not unless the attending engineer is also broadband savvy and performs one as a matter of course ?? It is not in the remit of a voice fault to perform a reset.
:)
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Yes, a HR would manifest itself on the router as a higher-than-usual attenuation. Experience shows me that a HR will fluctuate, and as such your attenuation should ??
No, the circuit will probably not be reset if it's a voice fault ...... not unless the attending engineer is also broadband savvy and performs one as a matter of course ?? It is not in the remit of a voice fault to perform a reset.
:)
Actually no, my attenuation seems pretty stable, at least according to my HG612. It may move by about 0.1db occasionally but its pretty minimal. I'm gonna ping Plusnet and see if they have the engineers notes yet and push for them to get BTO to reset the profile once the HR fault has been sorted.
Jeff
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The HR must be pretty miniscule, if at all there ??? Your post states that the engineer who has already visited said there was another "Possible HR". This could indicate that the TDR function we use to identify HR's, has actually shown a cable joint where the poundage (size) of the two cables changes from, for example, 0.4 Ali to 0.5 Cu ??
Of course I've no idea what the engineer on-site has seen, so have to trust in his experience. :)
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He didnt give much detail to be honest, he said they fixed one potential problem on the pole but the quiet line test and his kit was still showing another issue which he said need to be dealt with by the UG team. There were a few guys here and they seemed to know what they were doing, just have to wait and see what happens I guess.
No dropouts since they left, which is already an improvement.
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To have a synchronisation speed of ~65 Mbps at 360 metres from the cabinet is approximately what I would expect to obtain -- depending upon the condition of the cabling, the joints and the what-not. :)