General Discussion
  >> Fibre Broadband


Register (or login) on our website and you will not see this ad.


Pages in this thread: 1 | 2 | 3 | 4 | (show all)   Print Thread
Standard User nostos156
(newbie) Wed 15-Jul-15 19:06:04
Print Post

New Fibre connection, wondering about the stats.


[link to this post]
 
Hey guys. I'm on day 1 of my new Fibre connection and so have been pouring over related stats to check how my line is doing. However, as you guys are way more knowledgeable at this than me, how is it doing, what can I expect out of it over the coming days? Coming from 8Mb ADSL so obsessed over this is not the word!

(The UAS was from me moving the modem since I'm aware of the 48hr period before DLM start kicking in for that kind of stuff, powered it off before removing the cable so it could do the whole 'dying gasp' thing if that makes a difference)

Threw up a speedtest as well to see 'real world' values, as it were: Here

xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 22235 Kbps, Downstream rate = 76444 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 78650 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): 5.7 7.3
Attn(dB): 19.3 0.0
Pwr(dBm): 13.7 7.5
VDSL2 framing
Bearer 0
MSGc: 18 26
B: 239 237
M: 1 1
T: 23 42
R: 0 16
S: 0.0971 0.3781
L: 19768 5374
D: 1 1
I: 240 127
N: 240 254
Counters
Bearer 0
OHF: 15462136 2324618
OHFErr: 527 8
RS: 0 182303
RSCorr: 0 324
RSUnCorr: 0 0

Bearer 0
HEC: 3202 0
OCD: 96 0
LCD: 96 0
Total Cells: 3931720266 0
Data Cells: 75489296 0
Drop Cells: 0
Bit Errors: 0 0

ES: 289 8
SES: 0 0
UAS: 41 41
AS: 26005

Bearer 0
INP: 0.00 0.00
INPRein: 0.00 0.00
delay: 0 0
PER: 1.68 3.98
OR: 114.15 64.22
AgR: 78764.32 20063.54

Bitswap: 21206/21206 10/10

Total time = 7 hours 14 min 6 sec
FEC: 0 324
CRC: 527 8
ES: 289 8
SES: 0 0
UAS: 41 41
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 15 minutes time = 14 min 6 sec
FEC: 0 9
CRC: 12 3
ES: 8 3
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: 12 0
ES: 9 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 1 day time = 7 hours 14 min 6 sec
FEC: 0 324
CRC: 527 8
ES: 289 8
SES: 0 0
UAS: 41 41
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 = 7 hours 13 min 23 sec
FEC: 0 324
CRC: 527 8
ES: 289 8
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
#


xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 22216 Kbps, Downstream rate = 76444 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 78650 Kbps

Discovery Phase (Initial) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3959)
Medley Phase (Final) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3959)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 22216 kbps 76444 kbps
Actual Aggregate Tx Power: 7.5 dBm 13.7 dBm
====================================================================================
VDSL Band Status U0 U1 U2 U3 U4 D1 D2 D3
Line Attenuation(dB): 4.9 28.6 43.3 N/A N/A 14.2 36.8 55.4
Signal Attenuation(dB): 4.9 27.9 42.2 N/A N/A 16.0 36.5 55.4
SNR Margin(dB): 6.8 7.3 7.3 N/A N/A 5.6 5.6 5.6
TX Power(dBm): 0.4 -13.4 6.5 N/A N/A 10.8 8.3 6.8
#

Edited by nostos156 (Wed 15-Jul-15 19:09:36)

Standard User WWWombat
(knowledge is power) Wed 15-Jul-15 23:57:24
Print Post

Re: New Fibre connection, wondering about the stats.


[re: nostos156] [link to this post]
 
As those stats only show bearer 0, you haven't had G.INP activated on your line. I think you are on an ECI cabinet, in which case this won't happen for a while yet.

As things stand, your line is running OK, at a hair under the 6 dB target SNR margin.
An ES rate of 289 in 7 hours is low enough to not worry DLM yet - but you will need to make sure that rate is kept over 24 hours, and then kept over many days.

I had a line that kept an ES rate of 600-800 per day without worry (that was with PN, using the "speed" settings, which would allow 2880 ES's per day). That ES rate happened with a CRC rate around 10x as high.

It is, however, a high enough rate for you to want to keep monitoring - if your SNR drops a little, and the error rate increases a little, you will be well advised to re-synchronise. You'll get a small drop in speed (and, hopefully, a drop in the error rate) - but that is much easier to swallow than a DLM intervention.
Standard User nostos156
(newbie) Thu 16-Jul-15 00:00:51
Print Post

Re: New Fibre connection, wondering about the stats.


[re: WWWombat] [link to this post]
 
In reply to a post by WWWombat:
As those stats only show bearer 0, you haven't had G.INP activated on your line. I think you are on an ECI cabinet, in which case this won't happen for a while yet.

As things stand, your line is running OK, at a hair under the 6 dB target SNR margin.
An ES rate of 289 in 7 hours is low enough to not worry DLM yet - but you will need to make sure that rate is kept over 24 hours, and then kept over many days.

I had a line that kept an ES rate of 600-800 per day without worry (that was with PN, using the "speed" settings, which would allow 2880 ES's per day). That ES rate happened with a CRC rate around 10x as high.

It is, however, a high enough rate for you to want to keep monitoring - if your SNR drops a little, and the error rate increases a little, you will be well advised to re-synchronise. You'll get a small drop in speed (and, hopefully, a drop in the error rate) - but that is much easier to swallow than a DLM intervention.


Hi. Nope, It's the other cab, checked this before I got infinity. Afaik, G.INP is a different form of interleaving, and since I don't have that activated (yet, or at all), it stands to reason that it wouldn't be active?

As for now,

Still monitoring the lines, for some reason after 8PM the CRC errors got much higher (spikes of 100 or so every few minutes). DSL Uptime of 12 hours and 11,364 total CRC errors (most of them coming from 8PM onwards since earlier in the day it was only a few per every few mins).

Guessing it's to do with interference outside the house, like perhaps even the weather changing with the time of day since VDSL is supposedly so sensitive. Not liking it though, considering it might trigger interleaving which will make my pings [censored] vs ADSL.

However, that being said, LOS alarm errors are still strictly 0. CRCs have never been high enough to actually hurt the connection. Downlink is still 70+ so within margins of what I posted earlier.

Updated Stats:

xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 22497 Kbps, Downstream rate = 76684 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 78650 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 7.4
Attn(dB): 19.3 0.0
Pwr(dBm): 13.7 7.5
VDSL2 framing
Bearer 0
MSGc: 18 26
B: 239 237
M: 1 1
T: 23 42
R: 0 16
S: 0.0971 0.3781
L: 19768 5374
D: 1 1
I: 240 127
N: 240 254
Counters
Bearer 0
OHF: 26021122 2572788
OHFErr: 11548 9
RS: 0 3386626
RSCorr: 0 330
RSUnCorr: 0 0

Bearer 0
HEC: 5777 0
OCD: 189 0
LCD: 189 0
Total Cells: 2321724754 0
Data Cells: 121377580 0
Drop Cells: 0
Bit Errors: 0 0


xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 22494 Kbps, Downstream rate = 76684 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 78650 Kbps

Discovery Phase (Initial) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3959)
Medley Phase (Final) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3959)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 22494 kbps 76684 kbps
Actual Aggregate Tx Power: 7.5 dBm 13.7 dBm
====================================================================================
VDSL Band Status U0 U1 U2 U3 U4 D1 D2 D3
Line Attenuation(dB): 4.9 28.6 43.3 N/A N/A 14.2 36.8 55.4
Signal Attenuation(dB): 4.9 27.9 42.1 N/A N/A 16.0 36.5 55.4
SNR Margin(dB): 7.3 7.5 7.4 N/A N/A 5.5 5.6 5.6
TX Power(dBm): 0.4 -13.4 6.5 N/A N/A 10.8 8.3 6.8
#


Register (or login) on our website and you will not see this ad.

Standard User WWWombat
(knowledge is power) Thu 16-Jul-15 00:02:47
Print Post

Re: New Fibre connection, wondering about the stats.


[re: nostos156] [link to this post]
 
In reply to a post by nostos156:
what can I expect out of it over the coming days?


I should add that, longer term, you should probably expect crosstalk to have a gradual effect over time, and speeds to drop somewhat.

From attenuation, your line looks to be around 500m long.

Over 2 years, the "attainable" speed on my 400m line went from 88Mbps to 78Mbps, which was all from crosstalk. DLM intervened on a couple of occasions, taking another 6Mbps, but that was restored each time.
Standard User nostos156
(newbie) Thu 16-Jul-15 00:05:20
Print Post

Re: New Fibre connection, wondering about the stats.


[re: WWWombat] [link to this post]
 
Hi,

Accidentally didn't post all of the actual updated stats:

xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 22451 Kbps, Downstream rate = 76480 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 78650 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): 5.7 7.4
Attn(dB): 19.3 0.0
Pwr(dBm): 13.7 7.5
VDSL2 framing
Bearer 0
MSGc: 18 26
B: 239 237
M: 1 1
T: 23 42
R: 0 16
S: 0.0971 0.3781
L: 19768 5374
D: 1 1
I: 240 127
N: 240 254
Counters
Bearer 0
OHF: 26128138 2618152
OHFErr: 11571 9
RS: 0 996122
RSCorr: 0 330
RSUnCorr: 0 0

Bearer 0
HEC: 5799 0
OCD: 190 0
LCD: 190 0
Total Cells: 2348937311 0
Data Cells: 122018645 0
Drop Cells: 0
Bit Errors: 0 0

ES: 797 9
SES: 21 0
UAS: 41 41
AS: 43945

Bearer 0
INP: 0.00 0.00
INPRein: 0.00 0.00
delay: 0 0
PER: 1.68 3.98
OR: 114.15 64.22
AgR: 78764.32 20063.54

Bitswap: 35629/35630 39/39

Total time = 12 hours 13 min 6 sec
FEC: 0 330
CRC: 11571 9
ES: 797 9
SES: 21 0
UAS: 41 41
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 15 minutes time = 13 min 6 sec
FEC: 0 0
CRC: 216 0
ES: 32 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: 403 0
ES: 63 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 1 day time = 12 hours 13 min 6 sec
FEC: 0 330
CRC: 11571 9
ES: 797 9
SES: 21 0
UAS: 41 41
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 = 12 hours 12 min 25 sec
FEC: 0 330
CRC: 11571 9
ES: 797 9
SES: 21 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
#


My main concern is the level of errors and if they are acceptable because the line can handle them without breaking or losing speed.

As I hear, LOS errors are the serious ones that DLM will hammer you for, but I don't know what is a 'good' CRC error rate for VDSL, since on ADSL I was a solid 0 forever, lol.
Standard User nostos156
(newbie) Thu 16-Jul-15 00:08:54
Print Post

Re: New Fibre connection, wondering about the stats.


[re: nostos156] [link to this post]
 
Also, from a quick calculation, if I did it right, currently for the packets I received, 0.28% need to be retransmitted due to CRC errors.

Acceptable or unusually noisy line?
Standard User WWWombat
(knowledge is power) Thu 16-Jul-15 00:18:44
Print Post

Re: New Fibre connection, wondering about the stats.


[re: nostos156] [link to this post]
 
In reply to a post by nostos156:
Hi. Nope, It's the other cab, checked this before I got infinity. Afaik, G.INP is a different form of interleaving, and since I don't have that activated (yet, or at all), it stands to reason that it wouldn't be active?


OK. That would be the Huawei, then.

G.INP is a re-transmission mechanism, used in place of the severe FEC+interleaving put in place by a full, old-style, DLM intervention.

When G.INP is active, it *also* makes use of some amount of both FEC and interleaving ... but where the old-style settings would steal 8ms latency and 10-15% of bandwidth, the new-style (alongside G.INP) only steals around 0.2ms latency and 5% of bandwidth.

BT's current intention appears to be that G.INP starts out inactive on a new line, or after a DLM reset. After 2 days, it is likely to be turned on downstream - because, by default, it is only helpful.

However, BT's cock-up when rolling out G.INP originally means they have subsequently halted the rollout, and re-thought their plans. Your line might not go through G.INP activation for a while.

Still monitoring the lines, for some reason after 8PM the CRC errors got much higher (spikes of 100 or so every few minutes). DSL Uptime of 12 hours and 11,364 total CRC errors (most of them coming from 8PM onwards since earlier in the day it was only a few per every few mins).

The ES figure is much more important than CRC, as far as DLM is concerned. If you are getting spikes of CRC, then hopefully the ES rate isn't affected as badly.

Guessing it's to do with interference outside the house, like perhaps even the weather changing with the time of day since VDSL is supposedly so sensitive. Not liking it though, considering it might trigger interleaving which will make my pings [censored] vs ADSL.


If your cabinet/line is eligible for a G.INP setting, then crossing an error threshold is more likely to just turn on G.INP as a first step. You probably wouldn't notice that...

However, that being said, LOS alarm errors are still strictly 0. CRCs have never been high enough to actually hurt the connection.


DLM is more sensitive (to ES's, though). It is really configured under the assumption that you want broadcast quality to streamed video - which is hurt by bursts of CRC errors.

Updated Stats:


ES rate is by far the most interesting thing.
Standard User nostos156
(newbie) Thu 16-Jul-15 00:22:48
Print Post

Re: New Fibre connection, wondering about the stats.


[re: WWWombat] [link to this post]
 
Hrm, as for what you said about G.INP, I'll see what happens on day 3 then, when its likely to turn on a DRM starts inspecting the line.

I remember reading about that cock-up of a rollout, but I heard they'd fixed the issues back in April or so. The cab was only recently constructed afaik. It's all new - I'm probably the only customer using it at the moment! (sweet bliss)

As you can see the comparison from before the CRC started spiking and after, can you tell me what is interesting about the ES rate? Good, bad?

Edited by nostos156 (Thu 16-Jul-15 00:25:45)

Standard User nostos156
(newbie) Thu 16-Jul-15 00:25:07
Print Post

Re: New Fibre connection, wondering about the stats.


[re: nostos156] [link to this post]
 
Forgot to mention as well, my line used to be EO, and they built the cab to fix that. Afaik, only Hauwei cabs are involved in that type, so definitely is that model.
Standard User WWWombat
(knowledge is power) Thu 16-Jul-15 00:27:40
Print Post

Re: New Fibre connection, wondering about the stats.


[re: nostos156] [link to this post]
 
In reply to a post by nostos156:
Also, from a quick calculation, if I did it right, currently for the packets I received, 0.28% need to be retransmitted due to CRC errors.


CRC checks are made on all blocks transferred, even if there is no user data. Unless you keep the link 100% utilised, you're probably running at a much lower packet loss rate.

Acceptable or unusually noisy line?


My line ran happily at 600-800 ES/day, with 6,000-8,000 CRC per day. DLM intervened twice, on two occasions of spikes, one of which was a faulty line.

That kind of level was acceptable under the old DLM regime. If G.INP was applied instead of old-style FEC+interleaving, I'd almost certainly find it perfectly acceptable.

Your line is now running at around twice that rate, which would worry me slightly. However, G.INP intervention would probably make it OK.

I should say that it would worry me *only* because of the risk of DLM intervention. BT wouldn't consider it to be too noisy ... because DLM intervention would likely fix things.
Pages in this thread: 1 | 2 | 3 | 4 | (show all)   Print Thread

Jump to