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TBM

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I have a FTTC connection. Since the recent thunderstorms my connection speed has dropped from 42 to 37 Mbps and my ping from 20 to 14ms. Why would my ping get better ? And is the DLM stuck as in the past it has recovered to normality in 2 -3 days ?
 
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I doubt it has anything to do with thunderstorms, specially if the ping times changed. The internet is a mesh network, rather than a point to point network. Traffic may go through different paths, depending on availability, congestion, etc. Unless you have a trace route before and after to prove your traffic is actually going through the same points it's hard to compare ping times. Also what are you pinging? A lot of times people ping Google or their favourite DNS server. Well guess what? That is not a single server but a collection of load balanced servers around the world. What if a new node got added closer to you? You can't know for sure. If you want to measure your ping times it's best if you have someone else ping YOU. Thinkbroadband offers free brodband quality monitors, see one sample below. Ideally you should have a dynamic DNS service setup too so you can point to that and always have it resolve to your current IP. So set one up and you will be able to get a better understanding on how your internet connection is behaving. Again this won't be perfect as it can be affected by network changes but at least it's not a moving target like pinging a large DNS service is.

753fdd17db609a8cbdcecbeef52e0888575aed57.png
 
Thanks for the reply. I realise it isn't an absolute but I was using the ping time indicated by Ookla - I know I know. It consistently (for months and months) reported 20ms until my connection speed dropped which was also consistant until the recent thunderstorms. Straight afterwards the connection and ping times dropped - seems a spooky coincidence to me.
 
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Thanks for the reply. I realise it isn't an absolute but I was using the ping time indicated by Ookla - I know I know. It consistently (for months and months) reported 20ms until my connection speed dropped which was also consistant until the recent thunderstorms. Straight afterwards the connection and ping times dropped - seems a spooky coincidence to me.
It may not be a coincidence but still not be your connection. Maybe a link/router got damaged in the storm and now the traffic goes via a different path. The fact the ping times changed along with bandwidth indicates something else. Also you really need to see at what speed with vDSL modem is syncing at. This can change from time to time due to noise in the line. So without knowing what speed the line was syncing before it's hard to know. But if you router allows it do check the line sync speed now, as that's upper limit. A cold reboot (power off) can sometimes reset the sync speed to be better but I got tired of playing with my FTTC modem to get 2% better speed. Best is to focus on getting FTTP, if it is available in your area. All these FTTC speed silly things go away with full fibre...
 
I used the connection speeds as reported by the router (SNR margin has increased from low 3 to 4.7) and the ping time from Ookla in my first post. As I understand it DLM is holding the connection speed down but the better ping I don't understand. And as for FTTP - if only it were available.
 
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Are you using the same test endpont in Ookla when you have observed changes in ping times?
I just run Speedtest from a link on the desktop, I don't set an endpoint so that could explain the ping. However since the thunderstorm from a rock steady connection it has been over a week of reduced connection, ping reduction (maybe), SNR increase and 1Mbs increase in upload connection. DLM is taking it's time to recover this time around. The connection is not slow enough to log a fault, no noise on the line so I am stuck with it.
If it was fuel and I got 12% less for the same money as last week it would be called theft.
 
I have a FTTC connection. Since the recent thunderstorms my connection speed has dropped from 42 to 37 Mbs and my ping from 20 to 14ms. Why would my ping get better ? And is the DLM stuck as in the past it has recovered to normality in 2 -3 days ?
It's possible that the interleaving depth on your connection changed hence the lower latency.

With a higher (healthier) SNR DLM may have decided to back off the interleaving depth resulting in the lower latency.
 
Mine was the same. Use to be on 79999K/20000K

Code:
Stats recorded 09 Apr 2023 09:17:17

DSLAM type / SW version:    BDCM:0xc190 (193.144) / v0xc190
DSL mode:                   VDSL2 Profile 17a
Status:                     Showtime

          
                Downstream    Upstream
Line attenuation (dB):      11.9        0.0
Signal attenuation (dB):    Not available on VDSL2
Max speed (kbps):        86381        26060
Connection speed (kbps):    79999        20000
SNR margin (dB):            6.8        9.4
Power (dBm):                12.6        -1.6
Interleave depth:           16        1
INP:                        48.00        0
G.INP:                      Enabled        Not enabled
Vectoring status:           5 (VECT_UNCONFIGURED)     

RSCorr/RS (%):              0.0000        0.0000
RSUnCorr/RS (%):            0.0000        0.0000
ES/hour:                    0        0

Bearer 0
INP:                    48.00           0.00
INPRein:                0.00            0.00
delay:                         0               0
PER:                      0.00            6.13
OR:                     0.01            33.91
AgR:                    80614.82        20033.74

Bearer 1
INP:                    4.00            0.00
INPRein:                4.00            0.00
delay:                  3               0
PER:                    16.06           0.01
OR:                     95.62           0.01
AgR:                    95.62       0.01

Bitswap:                126/126         77/77

Stats recorded 21 Jun 2023 15:44:33

DSLAM type / SW version:    BDCM:0xc190 (193.144) / v0xc190
DSL mode:                   VDSL2 Profile 17a
Status:                     Showtime

          
                Downstream    Upstream
Line attenuation (dB):      12.2        0.0
Signal attenuation (dB):    Not available on VDSL2
Max speed (kbps):        78293        25968
Connection speed (kbps):    77375        20000
SNR margin (dB):            6.4        9.5
Power (dBm):                12.5        -0.9
Interleave depth:           8        1
INP:                        47.00        0
G.INP:                      Enabled        Not enabled
Vectoring status:           5 (VECT_UNCONFIGURED)     

RSCorr/RS (%):              0.0000        0.0000
RSUnCorr/RS (%):            0.0000        0.0000
ES/hour:                    0        0

Bearer 0
INP:                    47.00           0.00
INPRein:                0.00            0.00
delay:                  0               0
PER:                    0.00            6.13
OR:                     0.01            33.91
AgR:                    77454.67        20033.74

Bearer 1
INP:                    4.50            0.00
INPRein:                4.50            0.00
delay:                  3               0
PER:                    16.06           0.01
OR:                     79.68           0.01
AgR:                    79.68       0.01

Bitswap:                4/4             0/0
 
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Update: This morning around 3 DLM "shook the lead out" and granted me an extra 2Mbps, I'm not feeling so hard done by now that I know it isn't stuck - just darn slow to recover. Another 2 Mbps and I'll be back to where it was before the storm. Sadly I only have the ISP router and only have access to a fraction of the above line stats.
 
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Update: This morning around 3 DLM "shook the lead out" and granted me an extra 2Mbps, I'm not feeling so hard done by now that I know it isn't stuck - just darn slow to recover. Another 2 Mbps and I'll be back to where it was before the storm. Sadly I only have the ISP router and only have access to a fraction of the above line stats.
Yeah seen that befroe. After a period of line noise the sync speed is dropped. Then when stable again the DLM tries a little bit faster and waits to see if continues to be stable. The process will repeat again until it finds the ceiling. I am so glad all these malarkey it's gone with FTTP. I wish the government would have pushed telcos to upgrade to FTTP much earlier. But better late than never. And we know got a chance of some serious competition in some areas with the Altnets.
 
As in your post in another thread - I've been bypassed for being in a D.I.G road. It is an Island of FTTC in a sea of FTTP.
 
As in your post in another thread - I've been bypassed for being in a D.I.G road. It is an Island of FTTC in a sea of FTTP.
I think they are putting houses like your at the end of the queue since they will cost more to upgrade but no doubt they will do them since they will want to shutdown all copper services, specially in an area with high FTTP coverage...
 
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