Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Pages: 1 [2]

Author Topic: More weird upstream SNRM variation - line #2  (Read 3246 times)

burakkucat

  • Global Moderator
  • Senior Kitizen
  • *
  • Posts: 29449
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: More weird upstream SNRM variation - line #2
« Reply #15 on: September 12, 2019, 11:03:46 PM »

So that suggests line 3 also has an E-side now, no?

I wouldn't go as far as making that assumption. The disruption could be coupled into an E-side, D-side or an EO line. Once we reach the T-junction with the A87, there are various premises that could be the disrupter's source.

At the moment, without sight of the up-to-date network records, we are just guessing as to how the infrastructure merges into the background. For example, you have mentioned where it is possible to see one (or more) cables lying beside the road on the way to Heasta. I would be interested to know where it/they go(es) underground, before continuing westbound along the A87.
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 8676
  • Retd sw dev; A&A; 4 ◊ 7km ADSL2; IPv6; Firebrick
Re: More weird upstream SNRM variation - line #2
« Reply #16 on: September 12, 2019, 11:38:43 PM »

Indeed, I have probably assumed too much. It was a convenient way of explaining the disappearance of the nuisance line 3 upstream square wave.

The copper must be in ducts [?] somewhere between the Claymore restaurant and the Broadford exchange along the main road. Then further east there are plenty of FTTC cabs now in Sculamus and Breacais according to that codelook website [?] where there are a large number of houses stretching half a mile or so further east and  in the direction of the Skye bridge.

On the high moor to Heasta there is still only the one bundle visible by the roadside, according to Janet. Near the main road, in the suburb of Harapul, where the Heasta road leaves the main road at the Claymore restaurant (and the local vetís) there are about eight or nine houses right by the Heasta road, between the main road and a cattle grid where the road goes into to open pastures. All visible in Google Street View of course. I have no idea where exactly the copper is that services those houses and continues on towards Heasta. I suspect the copper is buried in a very shallow inadequate way on that stretch from the northern cattle grid where the houses peter out down southwards to the sharp little kink in the road where the bundle crosses the stream and starts to climb towards Heasta. There has been cable damage in the past in those fields, where animals are fed and vehicles pull off the road at the Harapul fank, where the ground is soft. Itís only at that bridge where you can start to see the copper, so in terms of topology, Iím wondering if the only significant node is that PCP discussed earlier, by the Claymore restaurant. And that spot, near the south roadside green cab, youíll recall, is near where Janet saw workmen active around the time when things first went to hell last month. They were not BT, but builders with a mini digger, working on a driveway.
« Last Edit: September 13, 2019, 01:54:38 AM by Weaver »
Logged

burakkucat

  • Global Moderator
  • Senior Kitizen
  • *
  • Posts: 29449
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: More weird upstream SNRM variation - line #2
« Reply #17 on: September 12, 2019, 11:45:36 PM »

. . . in terms of topology, Iím wondering if the only significant node is that PCP discussed earlier, by the Claymore restaurant.

That aligns with my suspicion.

Quote
And that spot, near the south roadside green cab, youíll recall, is near where Janet saw workmen active around the time when things first went to hell last month. They were not BT, but builders with a mini digger, working on a driveway.

Ah, yes. That's the location I can't pin-point (by searching for the corresponding background features in the current, old, Google Maps Street View image).
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 8676
  • Retd sw dev; A&A; 4 ◊ 7km ADSL2; IPv6; Firebrick
Re: More weird upstream SNRM variation - line #2
« Reply #18 on: September 18, 2019, 11:54:23 AM »

And now it seems things have gone back to the way they were.

* Line 3 has reassumed its old square wave behaviour. :-( Large (~4dB) height. I have set the line 3 upstream target to 9dB again in order to guard against a drop from 6dB all the way down to 2dB, which actually happened earlier today.

* Hereís line 2 for 2019-09-17 Ö 18 :



Combined upstream throughput reported by speedtesters has maybe improved slightly, again this is odd because the sync rates of line 3 has worsened slightly following a retrain this morning.

Live sync rates:
  #1: down 2913 kbps, up 532 kbps
  #2: down 2762 kbps, up 512 kbps
  #3: down 2927 kbps, up 272 kbps
  #4: down 2850 kbps, up 496 kbps

Firebrick current upstream rate limiters' IP PDU tx rates (egress speeds), in-force right now ::
    #1: 454050 bps
    #2: 436981 bps
    #3: 232146 bps
    #4: 423325 bps
Total combined rate: 1.546502 Mbps

Fractional upstream speed contributions:
    #1: 29.360%   [███████████████ ‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒]
    #2: 28.256%   [██████████████ ‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒]
    #3: 15.011%   [████████ ‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒]
    #4: 27.373%   [██████████████ ‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒‒]
Logged

burakkucat

  • Global Moderator
  • Senior Kitizen
  • *
  • Posts: 29449
  • Over the Rainbow Bridge
    • The ELRepo Project
Re: More weird upstream SNRM variation - line #2
« Reply #19 on: September 18, 2019, 10:22:56 PM »

I have to admit that I am totalled baffled by these current happenings.  ???
Logged
:cat:  100% Linux and, previously, Unix. Co-founder of the ELRepo Project.

Please consider making a donation to support the running of this site.

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 8676
  • Retd sw dev; A&A; 4 ◊ 7km ADSL2; IPv6; Firebrick
Re: More weird upstream SNRM variation - line #2
« Reply #20 on: September 19, 2019, 12:52:43 AM »

I am baffled too. That would now seem to have killed the theory that an E-side swap was carried out; cannot have had two E-side swaps, with a more recent one in the last couple of days; surely no way?

One thing that I need to recheck: is the SNRM variation due to attenuation variation, which is itself due to variation of resistance not variation in tx power output? Or is the SNRM due to changes in the noise level, be it crosstalk or other unrelated random interference - sources of interference going on / off?

Can check that by looking at the detailed stats for attenuation and power output.
Logged

ejs

  • Kitizen
  • ****
  • Posts: 2038
Re: More weird upstream SNRM variation - line #2
« Reply #21 on: September 19, 2019, 03:55:29 PM »

I think all modems only update the attenuation figure when the line trains. Therefore the only way to tell if the attenuation has changed would be to trigger a retrain.
Logged

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 8676
  • Retd sw dev; A&A; 4 ◊ 7km ADSL2; IPv6; Firebrick
Re: More weird upstream SNRM variation - line #2
« Reply #22 on: September 19, 2019, 07:23:19 PM »

I had not thought about that. Thanks for letting me know!  ;D  That explains a few things in the past. :-[  Iíll make sure to take account of that then.

Iíve just blown it for today, forgot and now Iíve missed my chance so next opportunity for a partner snapshot will have to be tomorrow now.
Logged

Weaver

  • Addicted Kitizen
  • *****
  • Posts: 8676
  • Retd sw dev; A&A; 4 ◊ 7km ADSL2; IPv6; Firebrick
Re: More weird upstream SNRM variation - line #2
« Reply #23 on: September 22, 2019, 02:04:42 PM »

Line 2 continues its bizarre upstream waggling, same 1.5dB height and it has not taken on the role of "the new line 3" at the moment

Logged
Pages: 1 [2]
 

anything