17-03-2023 22:14 - edited 17-03-2023 22:19
I recently self-installed Gig1 in my new home and noticed that compared to my VDSL connection, the ping is double and jitter is higher, particularly on downstream. Upstream performance is better than VDSL. I'm wondering if this could be due to contention, and if so, would both upstream and downstream be affected?
I've also looked into power levels but am unsure how to interpret them. There are a few marginal levels and the variance isn't too significant. Here are the power levels for reference:
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1 | 331000000 | -6.2 | 39 | QAM 256 | 25 |
2 | 139000000 | -3.1 | 39 | QAM 256 | 1 |
3 | 147000000 | -3.3 | 39 | QAM 256 | 2 |
4 | 155000000 | -3.5 | 38 | QAM 256 | 3 |
5 | 163000000 | -3.7 | 38 | QAM 256 | 4 |
6 | 171000000 | -3.8 | 39 | QAM 256 | 5 |
7 | 179000000 | -4.5 | 39 | QAM 256 | 6 |
8 | 187000000 | -4.5 | 39 | QAM 256 | 7 |
9 | 195000000 | -4.3 | 39 | QAM 256 | 8 |
10 | 203000000 | -4.6 | 39 | QAM 256 | 9 |
11 | 211000000 | -4.7 | 39 | QAM 256 | 10 |
12 | 219000000 | -5.1 | 33 | QAM 256 | 11 |
13 | 227000000 | -5.5 | 38 | QAM 256 | 12 |
14 | 235000000 | -5.4 | 39 | QAM 256 | 13 |
15 | 243000000 | -5.7 | 39 | QAM 256 | 14 |
16 | 251000000 | -5.9 | 39 | QAM 256 | 15 |
17 | 259000000 | -6.1 | 39 | QAM 256 | 16 |
18 | 267000000 | -6.3 | 39 | QAM 256 | 17 |
19 | 275000000 | -6.1 | 39 | QAM 256 | 18 |
20 | 283000000 | -6.1 | 39 | QAM 256 | 19 |
21 | 291000000 | -5.7 | 39 | QAM 256 | 20 |
22 | 299000000 | -5.7 | 39 | QAM 256 | 21 |
23 | 307000000 | -6.1 | 39 | QAM 256 | 22 |
24 | 315000000 | -5.7 | 39 | QAM 256 | 23 |
25 | 323000000 | -6.3 | 39 | QAM 256 | 24 |
26 | 339000000 | -5.9 | 39 | QAM 256 | 26 |
27 | 347000000 | -5.9 | 39 | QAM 256 | 27 |
28 | 355000000 | -6 | 39 | QAM 256 | 28 |
29 | 363000000 | -6.1 | 39 | QAM 256 | 29 |
30 | 371000000 | -6.2 | 39 | QAM 256 | 30 |
31 | 379000000 | -6 | 39 | QAM 256 | 31 |
Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1 | Locked | 39 | 0 | 0 |
2 | Locked | 39 | 638 | 124 |
3 | Locked | 39 | 103 | 5 |
4 | Locked | 38 | 126 | 13 |
5 | Locked | 38 | 185 | 11 |
6 | Locked | 39 | 155 | 1 |
7 | Locked | 39 | 79 | 13 |
8 | Locked | 39 | 85 | 1 |
9 | Locked | 39 | 60 | 0 |
10 | Locked | 39 | 25 | 10 |
11 | Locked | 39 | 5 | 0 |
12 | Locked | 33 | 49429 | 10 |
13 | Locked | 38 | 38 | 2 |
14 | Locked | 39 | 32 | 1 |
15 | Locked | 39 | 24 | 1 |
16 | Locked | 39 | 12 | 0 |
17 | Locked | 39 | 9 | 0 |
18 | Locked | 39 | 19 | 0 |
19 | Locked | 39 | 7 | 0 |
20 | Locked | 39 | 4 | 0 |
21 | Locked | 39 | 0 | 0 |
22 | Locked | 39 | 3 | 0 |
23 | Locked | 39 | 0 | 0 |
24 | Locked | 39 | 0 | 0 |
25 | Locked | 39 | 0 | 0 |
26 | Locked | 39 | 0 | 0 |
27 | Locked | 39 | 0 | 0 |
28 | Locked | 39 | 0 | 0 |
29 | Locked | 39 | 0 | 0 |
30 | Locked | 39 | 0 | 0 |
31 | Locked | 39 | 48 | 0 |
The previous owner had multiple TV connections, so there are several splitters and open wall points. I plan to disconnect the splitters tomorrow and retest. However, if the issue persists, what can be done to improve ping and jitter on my Gig1 connection?
on 18-03-2023 08:26
Gig 1 with mixed mode DOCSIS does have higher latency and jitter than FTTC / VDSL but also more raw bandwidth.
When removing splitters keep a careful eye on the changes to the Downstream and Upstream power levels, each splitter might have at least 4dB of signal loss, so for each removed the DS Power levels and SNR will rise & the US Power level will reduce.
As a guide refer to the section on optimum signal levels ...
https://pickmymodem.com/signal-levels-docsis-3-03-1-cable-modem/
18-03-2023 09:25 - edited 18-03-2023 09:27
Hi @enazyzed.
it might be useful to set up a BQM to map the latency, as virgin normally require these if action is required.
You can do that here: https://www.thinkbroadband.com/broadband/monitoring/quality
You may have to change some settings in the hub to make this work to make sure IMCP is not blocked. There are guides on how to do this on thinkbroadband’s website.
If you are still having an issue, I’ll flag it to the staff.
on 18-03-2023 10:17
Thank you for your reply, so I remove two splitters and you are right the power levels went up, the SNR stayed the same and the overall performance of the connection latency and jitter stayed the same. I am going to put it down to as you say the underlying technology and maybe a bit of oversubscription in the area.
I am still in my cooling of period so I have called to cancel for now.
Channel | Frequency (Hz) | Power (dBmV) | SNR (dB) | Modulation | Channel ID |
1 | 331000000 | -2.4 | 39 | QAM 256 | 25 |
2 | 139000000 | 0.7 | 39 | QAM 256 | 1 |
3 | 147000000 | 0.9 | 39 | QAM 256 | 2 |
4 | 155000000 | 0.4 | 39 | QAM 256 | 3 |
5 | 163000000 | 0.2 | 39 | QAM 256 | 4 |
6 | 171000000 | 0.3 | 39 | QAM 256 | 5 |
7 | 179000000 | 0.5 | 39 | QAM 256 | 6 |
8 | 187000000 | 0.4 | 39 | QAM 256 | 7 |
9 | 195000000 | 0.4 | 39 | QAM 256 | 8 |
10 | 203000000 | 0.4 | 39 | QAM 256 | 9 |
11 | 211000000 | 0.7 | 39 | QAM 256 | 10 |
12 | 219000000 | 0.9 | 32 | QAM 256 | 11 |
13 | 227000000 | -1.7 | 38 | QAM 256 | 12 |
14 | 235000000 | -1.2 | 39 | QAM 256 | 13 |
15 | 243000000 | -1.9 | 39 | QAM 256 | 14 |
16 | 251000000 | -1.9 | 39 | QAM 256 | 15 |
17 | 259000000 | -2.1 | 39 | QAM 256 | 16 |
18 | 267000000 | -2.3 | 39 | QAM 256 | 17 |
19 | 275000000 | -1.9 | 39 | QAM 256 | 18 |
20 | 283000000 | -2.1 | 39 | QAM 256 | 19 |
21 | 291000000 | -1.5 | 40 | QAM 256 | 20 |
22 | 299000000 | -1.9 | 39 | QAM 256 | 21 |
23 | 307000000 | -1.6 | 40 | QAM 256 | 22 |
24 | 315000000 | -2 | 39 | QAM 256 | 23 |
25 | 323000000 | -2.1 | 40 | QAM 256 | 24 |
26 | 339000000 | -1.8 | 40 | QAM 256 | 26 |
27 | 347000000 | -2.3 | 40 | QAM 256 | 27 |
28 | 355000000 | -2.2 | 40 | QAM 256 | 28 |
29 | 363000000 | -2.2 | 40 | QAM 256 | 29 |
30 | 371000000 | -2.3 | 40 | QAM 256 | 30 |
31 | 379000000 | -2.1 | 40 | QAM 256 | 31 |
Downstream bonded channels
Channel | Locked Status | RxMER (dB) | Pre RS Errors | Post RS Errors |
1 | Locked | 39 | 694 | 1299 |
2 | Locked | 39 | 16015 | 256 |
3 | Locked | 39 | 39069 | 1056 |
4 | Locked | 39 | 30068 | 1406 |
5 | Locked | 39 | 41746 | 1277 |
6 | Locked | 39 | 30444 | 543 |
7 | Locked | 39 | 31465 | 317 |
8 | Locked | 39 | 26671 | 1037 |
9 | Locked | 39 | 28922 | 961 |
10 | Locked | 39 | 2837 | 936 |
11 | Locked | 39 | 1708 | 919 |
12 | Locked | 32 | 36311 | 1726 |
13 | Locked | 38 | 131 | 2610 |
14 | Locked | 39 | 723 | 1636 |
15 | Locked | 39 | 677 | 1290 |
16 | Locked | 39 | 575 | 1030 |
17 | Locked | 39 | 381 | 541 |
18 | Locked | 39 | 347 | 504 |
19 | Locked | 39 | 476 | 562 |
20 | Locked | 39 | 492 | 609 |
21 | Locked | 40 | 684 | 1098 |
22 | Locked | 39 | 679 | 1229 |
23 | Locked | 40 | 719 | 1670 |
24 | Locked | 39 | 749 | 1556 |
25 | Locked | 40 | 618 | 1175 |
26 | Locked | 40 | 169 | 280 |
27 | Locked | 40 | 238 | 259 |
28 | Locked | 40 | 45 | 145 |
29 | Locked | 40 | 585 | 1197 |
30 | Locked | 40 | 564 | 904 |
31 | Locked | 40 | 1495 | 1441 |
on 20-03-2023 10:55
Hi enayzed,
Thank you for reaching out to us in our community and welcome back, it has been a while, sorry to hear you are facing high ping and jitter, I was unable to locate you on our system with the details we have for you, so I can help and have a look at things our end I will send you an invite into a private chat, once received please click on the purple envelope to accept.
Regards
Paul.
on 20-03-2023 12:02
Hi enayzed,
Thank you for joining me in a private chat, sorry to hear you have now cancelled due to the issues you are facing, we wish you all the luck and hope you may consider returning in the future, apologies again for any inconvenience caused.
Regards
Paul.