BricktonISP's profile

Regular Visitor

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3 Messages

Wed, Jan 13, 2021 5:00 AM

Packet Loss on Upstream

Equipment - Arieal Pole -> RG6 -> NID -> RG6-> Spliter 2way -> Netgear CM1150V -> Cat7 -> Netgear RAX200

 

Have had Comcast out who replaced line from pole to house, installled new NID box with filter and new RG6 from NID to Spliter (one to DVR and one to modem).  All SNR, Power and Speed look good to me and consistently wired speed down is 800-900Mbps and up is 35-44Mbps with Jitter on avg is 2-4ms, Ping on avg is 9-20ms,   

 

PROBLEM:  main issue packet loss upwards of 3-4% on upstream with less than 1% downstream.  This causes video/audio choppiness in Zoom/Google Meets for teacher, student and remote worker. seems to be focus on upstream problem.  Also in logs seeing T3 timeouts today - but typically see CM-Status message Event Type code 5 / Chan ID 37 messages.

 

ANY IDEAS/SUGGESTIONS - seems to be upstream from me?  How would I get comcast to look into line issue since between them and I we've changed out everything from workstaiton to pole.

 

 

 

In Log see messages:

TimePriorityDescription
Wed Jan 13 00:01:07 2021Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=78:d2:94:XX:XX:XX;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Tue Jan 12 18:45:44 2021Notice (6)CM-STATUS message sent. Event Type Code: 5; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:XX:XX:XX;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Tue Jan 12 18:45:31 2021Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=78:d2:94:XX:XX:XX;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Tue Jan 12 18:45:26 2021Notice (6)TLV-11 - unrecognized OID;CM-MAC=78:d2:94:XX:XX:XX;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:XX:XX:X;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=78:d2:94:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

 

 

What can be checked.   I have verified all connections are tight, replaced all eithernet with Cat7 for wired connections.  

 

CM1150V status page

Downstream Bonded Channels
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM2565549000000 Hz4.8 dBmV41.3 dB00
2LockedQAM2562531000000 Hz4.5 dBmV41.1 dB00
3LockedQAM2563537000000 Hz4.7 dBmV41.1 dB00
4LockedQAM2564543000000 Hz4.6 dBmV41.2 dB00
5LockedQAM2566555000000 Hz4.9 dBmV41.2 dB00
6LockedQAM2567561000000 Hz5.1 dBmV41.3 dB00
7LockedQAM2568567000000 Hz5.1 dBmV41.2 dB00
8LockedQAM2569573000000 Hz5.2 dBmV41.4 dB00
9LockedQAM25610579000000 Hz5.3 dBmV41.2 dB00
10LockedQAM25611585000000 Hz5.5 dBmV41.4 dB00
11LockedQAM25612591000000 Hz5.5 dBmV41.5 dB00
12LockedQAM25613597000000 Hz5.5 dBmV41.3 dB00
13LockedQAM25614603000000 Hz5.7 dBmV41.4 dB00
14LockedQAM25615609000000 Hz5.6 dBmV41.3 dB00
15LockedQAM25616615000000 Hz5.8 dBmV41.2 dB00
16LockedQAM25617621000000 Hz5.9 dBmV41.1 dB00
17LockedQAM25618627000000 Hz6 dBmV41.2 dB00
18LockedQAM25619633000000 Hz5.9 dBmV41.2 dB00
19LockedQAM25620639000000 Hz5.9 dBmV41 dB00
20LockedQAM25621645000000 Hz6.4 dBmV41.2 dB00
21LockedQAM25622651000000 Hz6.6 dBmV41.2 dB00
22LockedQAM25623657000000 Hz6.7 dBmV41.3 dB00
23LockedQAM25624663000000 Hz6.6 dBmV41.2 dB00
24LockedQAM25625669000000 Hz6.7 dBmV41.4 dB00
25LockedQAM25626675000000 Hz6.7 dBmV41.1 dB00
26LockedQAM25627681000000 Hz6.4 dBmV41.5 dB00
27LockedQAM25628687000000 Hz6.6 dBmV41.5 dB00
28LockedQAM25629693000000 Hz6.4 dBmV41.5 dB00
29LockedQAM25630699000000 Hz6.7 dBmV41.6 dB00
30LockedQAM25631705000000 Hz7 dBmV41.8 dB00
31LockedQAM25632711000000 Hz7.1 dBmV41.8 dB00
32Not LockedUnknown00 Hz0.0 dBmV0.0 dB00

 

 

 

Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA15120 Ksym/sec35600000 Hz42.8 dBmV
2LockedATDMA25120 Ksym/sec29200000 Hz42.8 dBmV
3LockedATDMA35120 Ksym/sec22800000 Hz42.3 dBmV
4LockedATDMA45120 Ksym/sec16400000 Hz42 dBmV
5Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV

 

 

Downstream OFDM Channels
ChannelLock
Status
Modulation /
Profile ID
Channel
ID
FrequencyPowerSNR /
MER
Active Subcarrier
Number Range
Unerrored
Codewords
Correctable
Codewords
Uncorrectable
Codewords
1Locked0 ,1 ,2 ,337762000000 Hz5.9 dBmV41.8 dB1108 ~ 29871129852041089024350
2Not Locked000 Hz0 dBmV0.0 dB0 ~ 4095000

Responses

Regular Visitor

 • 

3 Messages

5 m ago

Ok good thanks for the update - glad to see if somewhere upstream they can see an issue 

 

I have Cat7 newly cabled to all internal nodes

I was running IPv6 mode but turned that off to see if IPv4 would respond better as well.

I have had 2 different tech appointments -- most recently they replaced wires from ariel pole to nid to splitter (2-way supplied by Comcast) one to modem one to dvr.

 

Can only assume something upstream -- I even took on 30 day trial of XR7 modem/router but given no details in the log on that thing nothing notably different - went back to my CM1150v customer-owned - at latest firmware v04.0202 confirmed with Netgear and Comcast that's the latest.   Kinda at wits end to get stable.

 

Look forward to the response from the upstream CMTS team or line/pole teams in my area to review.

 

EG

Expert

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87.1K Messages

5 m ago

The signal stats are o/k but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) / return path somewhere.

 

There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.

 

I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They will be able to poll the CMTS to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem. You should get a reply here in your topic. Good luck !

Regular Visitor

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3 Messages

5 m ago

Updated CM1150V Log with more Event Type criticals/notices received in last 2 days since the original post.   Still, awaiting Comcast/Xfinity CMTS Techs response from the escalation in this thread to respond?   

 

TimePriorityDescription
Thu Jan 14 13:01:13 2021Notice (6)CM-STATUS message sent. Event Type Code: 22; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 14 13:00:42 2021Notice (6)CM-STATUS message sent. Event Type Code: 20; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 14 04:31:44 2021Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 19:23:07 2021Notice (6)CM-STATUS message sent. Event Type Code: 22; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 19:22:41 2021Notice (6)CM-STATUS message sent. Event Type Code: 20; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 17:33:45 2021Notice (6)CM-STATUS message sent. Event Type Code: 22; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 17:32:51 2021Notice (6)CM-STATUS message sent. Event Type Code: 20; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 17:01:35 2021Notice (6)CM-STATUS message sent. Event Type Code: 22; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 17:01:08 2021Notice (6)CM-STATUS message sent. Event Type Code: 20; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 16:32:24 2021Notice (6)CM-STATUS message sent. Event Type Code: 22; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 16:32:00 2021Notice (6)CM-STATUS message sent. Event Type Code: 20; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Wed Jan 13 00:01:07 2021Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Tue Jan 12 18:45:44 2021Notice (6)CM-STATUS message sent. Event Type Code: 5; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Tue Jan 12 18:45:31 2021Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Tue Jan 12 18:45:26 2021Notice (6)TLV-11 - unrecognized OID;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)No Ranging Response received - T3 time-out;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:01:5c:66:54:69;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=78:d2:94:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

 

EG

Expert

 • 

87.1K Messages

5 m ago

Please have patience. We have been told by the powers that be that they are a bit shorthanded at this time. 

 

I can try re-escalating this again if you don't get a response soon.

Official Employee

 • 

375 Messages

5 m ago

@BricktonISP Thank you so much for taking the time to reach out to us regarding the connection issues that you have been experiencing. I am truly sorry for the delay in our response and am very grateful for your time and patience. I would love to get to the bottom of the connection issues, can you please reach out through private message (you can find out how with this link https://comca.st/3pntKrb) with your first and last name, name on the account if different and service address and we will work to get to the bottom of this with you? 

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