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Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Frequent Visitor

Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Hey there!

Rather than go way too deep on this, I'll keep it brief. 

I've been experiencing significant issues with signal continuity and strength ever since I purchased gigabit through xfinity. 

To narrow down where the packet loss has been initiated from, I now regularly run signal trace programs to determine the generation point, and I regularly have the packet loss land at Hops 2 and 4, which logic would tell you are the local data centers.

Does anyone have any experience with getting Comcast to address this issue?

 

For posterity's sake, My hardware (purchased about 3 months ago if I had to guess) :

Arris SB8200 Modem, Current Firmware - https://www.amazon.com/ARRIS-SURFboard-Approved-SB8200-Frustration/dp/B07DY16W2Z/ref=sr_1_1?keywords...

 

ASUS AC3100, Current Firmware -  https://www.amazon.com/Dual-Band-supporting-AiProtection-Accelerator-RT-AC88U/dp/B016EWKQAQ/ref=sr_1...

 

Also, here is a log of my 10 (if I counted right) most recent Modem events:

 

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"        
10/31/2019 12:21 67061600 6   "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 2436694066 6   "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:00 82000200 3   "No Ranging Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3   "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 68001101 3   "TFTP Request Retries exceeded, CM unable to register "
01/01/1970 00:01 68000500 3   "TFTP failed - Request sent - No Response;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3   "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 82000200 3   "No Ranging Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3   "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
09/23/2019 15:32 82000100 3   "No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"
09/23/2019 15:32 84000100 3   "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1;"

 

Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues)

I also notice that most of these type of forum questions involve someone asking about power levels.

We had a technician come over not too long ago and he said he noticed the power levels were low, and said he increased them.

Here they are at current:

61EF5C46-E496-4A11-8D75-C43F1B1FF2A3.png

Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

If you can figure this out and you're in the Atlanta Area, I will personally arrange for donuts to be delivered to your location at a time and place of your choosing.

Expert

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Can't see your pic. Since you are a new poster, it needs to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting it at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to it here.



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Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

I'll probably just copy the text when I get back home. Easy Peasy. lol

Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Current Status on Modem:

 

Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
2 Locked QAM256 483000000 Hz -1.9 dBmV 41.8 dB 0 0
3 Locked QAM256 489000000 Hz -1.6 dBmV 41.8 dB 0 0
4 Locked QAM256 495000000 Hz -1.2 dBmV 42.0 dB 0 0
5 Locked QAM256 501000000 Hz -0.7 dBmV 41.9 dB 0 0
6 Locked QAM256 507000000 Hz 0.1 dBmV 42.3 dB 0 0
7 Locked QAM256 513000000 Hz 0.4 dBmV 42.3 dB 0 0
8 Locked QAM256 519000000 Hz 0.4 dBmV 42.4 dB 0 0
9 Locked QAM256 525000000 Hz 0.3 dBmV 42.1 dB 0 0
10 Locked QAM256 531000000 Hz 0.4 dBmV 42.2 dB 0 0
11 Locked QAM256 537000000 Hz 0.5 dBmV 41.9 dB 0 0
12 Locked QAM256 543000000 Hz 0.8 dBmV 42.2 dB 0 0
13 Locked QAM256 555000000 Hz 0.9 dBmV 42.1 dB 0 0
14 Locked QAM256 561000000 Hz 0.4 dBmV 41.9 dB 0 0
15 Locked QAM256 567000000 Hz 0.7 dBmV 41.9 dB 0 0
16 Locked QAM256 573000000 Hz 0.7 dBmV 41.6 dB 0 0
17 Locked QAM256 579000000 Hz 0.5 dBmV 41.9 dB 0 0
18 Locked QAM256 585000000 Hz 0.8 dBmV 42.1 dB 0 0
19 Locked QAM256 591000000 Hz 0.4 dBmV 42.0 dB 0 0
20 Locked QAM256 597000000 Hz 0.6 dBmV 41.8 dB 0 0
21 Locked QAM256 603000000 Hz 0.4 dBmV 41.6 dB 0 0
22 Locked QAM256 609000000 Hz 0.9 dBmV 42.0 dB 0 0
23 Locked QAM256 615000000 Hz 0.8 dBmV 41.8 dB 0 0
24 Locked QAM256 621000000 Hz 0.7 dBmV 41.7 dB 0 0
25 Locked QAM256 627000000 Hz 0.5 dBmV 41.5 dB 0 0
26 Locked QAM256 633000000 Hz 0.7 dBmV 41.7 dB 0 0
27 Locked QAM256 639000000 Hz 0.7 dBmV 41.6 dB 0 0
28 Locked QAM256 645000000 Hz 0.8 dBmV 41.5 dB 0 0
29 Locked QAM256 651000000 Hz 0.7 dBmV 41.5 dB 0 0
30 Locked QAM256 657000000 Hz 0.4 dBmV 41.3 dB 0 0
31 Locked QAM256 663000000 Hz 0.6 dBmV 41.5 dB 0 0
32 Locked QAM256 669000000 Hz 0.5 dBmV 41.3 dB 0 0
37 Locked Other 690000000 Hz 0.9 dBmV 40.0 dB 1676894564 0


 

Expert

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Those are very good. Please post the upstream channels and the latest RF error / event log entries as well.


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Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Sure thing, EG. 
I'll get the Upstream channels when I get home, but the event log info is part of that first post.
I appreciate you taking a look at this.

Expert

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues


@Cdelaet1 wrote:

 but the event log info is part of that first post.


Yes I understand, but as I wrote, I would like to see "the latest" entries and if they are accumulating.



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Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 16 Locked SC-QAM Upstream 16600000 Hz 6400000 Hz 35.0 dBmV
2 13 Locked SC-QAM Upstream 35800000 Hz 6400000 Hz 37.0 dBmV
3 14 Locked SC-QAM Upstream 29400000 Hz 6400000 Hz 36.0 dBmV
4 15 Locked SC-QAM Upstream 23000000 Hz 6400000 Hz 35.0 dBmV


There is the upstream channels and.....

Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Most recent logs:

 

Date Time Event ID Event Level Description
11/07/2019 18:29 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"
11/06/2019 21:00 74010100 6 "CM-STATUS message sent. Event Type Code: 24; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1.;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"
11/06/2019 20:33 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"
11/06/2019 16:06 74010100 6 "CM-STATUS message sent. Event Type Code: 24; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1.;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"
11/06/2019 13:42 67061600 6 "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 2436694066 6 "Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:00 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[I DELETED THIS];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
11/06/2019 13:44 2436694044 3 "Resetting the cable modem due to docsDevResetNow"
11/06/2019 02:32 82000500 3 "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[I DELETED THIS];CMTS-MAC=[I DELETED THIS];CM-QOS=1.1;CM-VER=3.1;"

 

Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

@EG any throughts now that I got the additional info to you?

Expert

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

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) 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 !



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Official Employee

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

Greetings, Cdelaet1! We appreciate you taking the time to reach out to us here on the forums. We hope you are having an amazing day. We apologize to hear of the issues you are running into with your internet connection. That's certainly frustrating. As EG has pointed out, there are a few more things we would need to take a deep dive into on your connection. Can you please send us a PM with your first and last name so we may further assist you?

 

To send a private message, please click the name "Comcast_Support" then select "Send a Message" on the right side.


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Frequent Visitor

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues

@Comcast_Support 

I just sent my name and contact information to you one more time, have you received it?

Official Employee

Re: Significant Packet Loss at Hops 2 and 4 (Connection stability issues


@Cdelaet1 wrote:

@Comcast_Support 

I just sent my name and contact information to you one more time, have you received it?


We did get your messages, thanks. Working on this now.

Ken


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