Community FAQ
cancel
Turn on suggestions
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.
Showing results for 
Search instead for 
Did you mean: 

SNR / Dropout help please

NC55
Joining in

on ‎26-10-2024 16:30

Continued connection dropouts, after 4 engineer visits, multiple equipment changes, exec complaints team issues/no follow ups, I am at my wits end. Thank you

 

 

3.0 Downstream channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1355000000239QAM 25628
21390000002.438QAM 2561
31470000001.538QAM 2562
41550000001.538QAM 2563
51710000001.538QAM 2565
61790000001.738QAM 2566
71870000001.838QAM 2567
8195000000238QAM 2568
92030000001.938QAM 2569
102110000002.238QAM 25610
112190000002.138QAM 25611
122270000001.938QAM 25612
132350000001.538QAM 25613
142430000001.538QAM 25614
152510000001.431QAM 25615
16259000000238QAM 25616
172670000001.938QAM 25617
182750000001.839QAM 25618
192830000001.738QAM 25619
202910000001.838QAM 25620
212990000001.738QAM 25621
223070000001.639QAM 25622
233150000001.538QAM 25623
243230000001.538QAM 25624
253310000001.539QAM 25625
263390000001.639QAM 25626
273470000001.539QAM 25627
283630000001.637QAM 25629
293710000001.739QAM 25630
303790000001.738QAM 25631
313870000001.637QAM 25632

3.0 Downstream channels

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1Locked39165906763229
2Locked38179871799160
3Locked38150699736013
4Locked38130323695594
5Locked38113258632298
6Locked3896574564964
7Locked3873503439417
8Locked3872779435416
9Locked3867766405719
10Locked3867759402157
11Locked3863169367874
12Locked3859291331585
13Locked3851009277019
14Locked3842307229104
15Locked3139374206501
16Locked3838390197196
17Locked3835593176220
18Locked3935174175695
19Locked3831751156564
20Locked3830463152460
21Locked3829779149729
22Locked3927358139444
23Locked3826633137691
24Locked3825990140245
25Locked3924819136605
26Locked3924033131550
27Locked3923130126855
28Locked3723741132151
29Locked3922495127211
30Locked3824716138666
31Locked3724086135063

3.1 Downstream channels

Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
33944K1840QAM 40961108

3.1 Downstream channels

Channel ID Locked Status RxMER Data (dB) PLC Power (dBmV) Corrected errors (Active Profile) Uncorrectable errors (Active Profile)
33Locked414.62740584010248222

 

3.0 Upstream channels

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
06030000034.35120QAM 641
15370000034.35120QAM 642
24620000034.35120QAM 643
339400000345120QAM 644
43260000034.55120QAM 649
52360000034.35120QAM 6410

3.0 Upstream channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
0ATDMA0600
1ATDMA0600
2ATDMA0600
3ATDMA0600
4ATDMA0600
5ATDMA0610

 

Time Priority Description
26-10-2024 16:17:03noticeGUI Login Status - Login Success from LAN interface
26-10-2024 16:07:58noticeCM-STATUS message sent. Event Type Code: 16; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:07:24noticeREGISTRATION COMPLETE - Waiting for Operational status
26-10-2024 16:07:17noticeDS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:07:16noticeTLV-11 - unrecognized OID;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:07:09warningDHCP WARNING - Non-critical field invalid in response ;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:07:07noticeHonoring MDD; IP provisioning mode = IPv4
26-10-2024 16:07:01criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:06:52warningToD request sent - No Response received;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:06:50criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:06:41criticalSYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:06:24criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:06:20criticalStarted Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:06:00noticeREGISTRATION COMPLETE - Waiting for Operational status
26-10-2024 16:05:58warningTCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:05:34criticalStarted Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:05:34criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:05:32criticalStarted Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:05:31criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:59noticeDS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:57noticeTLV-11 - unrecognized OID;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:52warningDHCP WARNING - Non-critical field invalid in response ;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:48noticeHonoring MDD; IP provisioning mode = IPv4
26-10-2024 16:04:38warningToD request sent - No Response received;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:37criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:28criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:28criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:04:08criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:03:55criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:03:55criticalStarted Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:03:53criticalStarted Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:03:53criticalNo Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:03:47criticalStarted Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
26-10-2024 16:01:48noticeGUI Login Status - Login Success from LAN interface
26-10-2024 16:01:29noticeGUI Login Status - Login Fail from LAN interface
25-10-2024 20:08:26noticeGUI Login Status - Login Success from LAN interface
25-10-2024 12:09:22noticeGUI Login Status - Login Success from LAN interface
20-10-2024 17:12:54noticeGUI Login Status - Login Success from LAN interface
0 Kudos
11 REPLIES 11

NC55
Joining in
In response to Sabrina_B

on ‎30-10-2024 14:27

Hi Sabrina,

I had my 5th engineer visit this afternoon, who replaced the copper interior connectors/adapters with fibre ones.

This has not resolved the issues, seemingly has exacerbated them and in fact my internet is now dropping in and out almost every 2 minutes. 

 

Logs below. I have a complaint open with the exec team but also continuing the conversation here for visibility. It frankly is beyond belief that this now has been going on for over 3 months, 5 or 6 visits over this time, while the data is pretty clear as to the issues, as per comments from the community above. I shouldn't have to do this, but to support VM in their ability to troubleshoot and fix the problem, I have added some notes from chat gpt re the logs. 

 

3.0 Downstream channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
11390000000.839QAM 2561
21470000000.739QAM 2562
31550000000.738QAM 2563
41630000000.639QAM 2564
51710000000.538QAM 2565
61790000000.538QAM 2566
71870000000.638QAM 2567
81950000000.838QAM 2568
9211000000138QAM 25610
10219000000138QAM 25611
11227000000138QAM 25612
12235000000138QAM 25613
132430000000.938QAM 25614
142510000000.938QAM 25615
152590000000.938QAM 25616
162670000000.938QAM 25617
172750000000.838QAM 25618
182830000000.838QAM 25619
192910000000.938QAM 25620
202990000000.938QAM 25621
213070000000.938QAM 25622
223150000000.838QAM 25623
233230000000.738QAM 25624
243310000000.738QAM 25625
253390000000.838QAM 25626
263470000000.838QAM 25627
273550000000.838QAM 25628
283630000000.838QAM 25629
293710000000.838QAM 25630
303790000000.838QAM 25631
313870000000.738QAM 25632

3.0 Downstream channels

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1Locked39206698999994
2Locked392579771151017
3Locked382334561102569
4Locked39184854979354
5Locked38165777913840
6Locked38140278808379
7Locked38111392664797
8Locked38109858658930
9Locked38102875611667
10Locked3896067570051
11Locked3890779529234
12Locked3886140486878
13Locked3874332405120
14Locked3863302343434
15Locked3858859314320
16Locked3857653298931
17Locked3853189266767
18Locked3852586262759
19Locked3847960234792
20Locked3847440239805
21Locked3845847231226
22Locked3842285215767
23Locked3840453209459
24Locked3839436211774
25Locked3836406199519
26Locked3836679199613
27Locked3834773190748
28Locked3835021193982
29Locked3833953191780
30Locked3836607204755
31Locked3835363198204

3.1 Downstream channels

Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
33944K1840QAM 40961108

3.1 Downstream channels

Channel ID Locked Status RxMER Data (dB) PLC Power (dBmV) Corrected errors (Active Profile) Uncorrectable errors (Active Profile)
33Locked414.44141677036

383764

 

Network Log

Time Priority Description
30-10-2024 14:22:26noticeGUI Login Status - Login Success from LAN interface
30-10-2024 14:06:48noticeGUI Login Status - Login Success from LAN interface
30-10-2024 13:15:19noticeCM-STATUS message sent. Event Type Code: 24; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0 1 2 3.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:15:19noticeCM-STATUS message sent. Event Type Code: 4; Chan ID: 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1
30-10-2024 13:15:19noticeCM-STATUS message sent. Event Type Code: 5; Chan ID: 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;
30-10-2024 13:15:19noticeCM-STATUS message sent. Event Type Code: 23; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:15:19noticeCM-STATUS message sent. Event Type Code: 22; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:34criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:34warningMDD message timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:28warningMDD message timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:28criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:25criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:13noticeCM-STATUS message sent. Event Type Code: 4; Chan ID: 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1
30-10-2024 13:14:13noticeCM-STATUS message sent. Event Type Code: 24; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0 1 2 3.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:13noticeCM-STATUS message sent. Event Type Code: 5; Chan ID: 2 3 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;
30-10-2024 13:14:13noticeCM-STATUS message sent. Event Type Code: 23; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:14:13noticeCM-STATUS message sent. Event Type Code: 22; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:13:31criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:13:30warningMDD message timeout;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:13:27criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:12:15noticeREGISTRATION COMPLETE - Waiting for Operational status
30-10-2024 13:12:07noticeDS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:12:06noticeTLV-11 - unrecognized OID;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:11:59warningDHCP WARNING - Non-critical field invalid in response ;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:11:57noticeHonoring MDD; IP provisioning mode = IPv4
30-10-2024 13:05:01criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:57warningToD request sent - No Response received;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:55criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:45criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:45criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:34criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:34criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:12criticalSYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
30-10-2024 13:04:12criticalReceived Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
0 Kudos

NC55
Joining in
In response to NC55

on ‎30-10-2024 14:28

1. Downstream Channel Status (Power, SNR, and Errors)

  • Power Levels: Downstream power levels range from 0.5 to 1 dBmV, which generally falls within an acceptable range. However, values close to zero can be more susceptible to fluctuations, especially in cases of network strain or environmental noise.
  • SNR (Signal-to-Noise Ratio): Most channels show an SNR of 38 dB, which is decent. However, some channels like Channel 1 have slightly higher SNR values (up to 39 dB). While 38-39 dB is generally good, fluctuations below this range may cause instability.
  • Pre and Post RS Errors:
    • Pre-RS (Reed-Solomon) errors are typically correctable, but they provide an indication of potential noise or interference in the line. Your report shows some high counts in the early channels, notably Channel 1 (206,698 pre-RS errors) and Channel 2 (257,977 pre-RS errors).
    • Post-RS errors are more critical since these indicate errors that were uncorrectable, impacting data integrity. Channels 1, 2, and 3 have high post-RS error counts, suggesting significant noise or interference leading to data loss on these frequencies.

2. DOCSIS 3.1 Downstream Channel

  • Channel 33: This OFDM channel, using QAM 4096 modulation, shows a locked status with an RxMER (Received Modulation Error Ratio) of 41 dB, which is strong. However, the uncorrectable errors (383,764) and the massive count of corrected errors (over 4 billion) are a sign of substantial signal integrity issues on this channel. Corrected errors indicate the system is heavily compensating, but high uncorrectable errors are a problem.

3. Event Logs Analysis

The logs show several key events that align with signal issues:

  • CM-STATUS Messages (around 13:15:19): Various Event Type Codes (4, 5, 22, 23, 24) suggest communication status updates across multiple channels. This could indicate fluctuating connection stability across the downstream channels, potentially linked to signal degradation.
  • MDD Message Timeout: The "MDD message timeout" warnings indicate the modem is struggling to maintain a Management Data Delivery message, which is essential for staying synchronized with the network. This often points to noise or signal disruption on the line.
  • Critical SYNC Timing Synchronization Failures: Multiple synchronization failures indicate the modem is unable to maintain proper timing alignment with the network. Timing issues can arise from poor signal quality, damaged cabling, or interference, causing substantial downstream issues.

Recommended Actions

Based on this data, here’s what VMO2’s technical team should ideally do:

  1. Physical Line Inspection:

    • Inspect for Fiber Cleanliness: Ensure the fiber connections are clean, as dirt or dust can degrade the signal quality.
    • Optical Power Check: Verify that the optical power reaching the customer’s premises is within acceptable levels. If power is low, it may require adjustments at the node or replacing fiber segments.

  2. Replace the Optical Network Unit (ONU):

    • Given the high number of post-RS and uncorrectable errors, the ONU may be malfunctioning. Replacing the ONU could help stabilize the downstream signal.

  3. Switch CBT Port (if needed):

    • If power and signal quality issues persist after cleaning and replacing the ONU, it could indicate issues with the CBT port (Connection Block Terminal) or cabling. Switching to a different port may resolve the instability if the original port is damaged or has poor connectivity.

  4. Run a New Fiber Drop:

    • If all other steps fail, installing a new fiber drop may be necessary. VMO2 would handle the permit management for any public space work required. This includes:
      • Obtaining Street Works Permits from the local council if the drop needs to go under public roads or sidewalks.
      • Utility Coordination: Ensuring other services (e.g., water, electricity) are not affected by the new line.
    • Timeline: Permit acquisition and scheduling could extend the repair timeframe to several weeks, especially if there are restrictions on public space work.

  5. Monitor Post-Installation:

    • After replacing the necessary components, VMO2 should monitor the line over several days to check for stability and verify that error counts remain within acceptable limits.
0 Kudos
Top