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Arris SB8200 upstream not bound to DOCSIS 3.1 - power levels are too low according to Arris

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Arris SB8200 upstream not bound to DOCSIS 3.1 - power levels are too low according to Arris

Arris SB8200

Xfinity Gigabit Plan

 

Hardwired via Gigabit Ethernet Adapter

Max Dowload Speeds ~600Mbps

Max Upload Speeds ~40Mbps

 

Spoke to an Xfinity Support person regarding the upstream channels LOCKED to DOCSIS 3.0, was told that's all I'll get with current equipment and a customer-owned modem.

 

Next, spoke with Arris support, and was told the power levels on the upstream channels are too low, should be within 45-51dBmV to be locked to DOCSIS 3.1 upstream channels. He also indicated the low power on the upstream would negatively affect max download speeds. (?)

 

I also asked Arris about Link Aggregation, and the support rep said it was dependent on the modem's firmware version, and said the feature was available on FWs 0200.174F and above, which my modem's firmware is above that range.

 

**Any input/help/advice is sincerely appreciated**

 

Event Log:

Date Time Event ID Event Level Description
11/17/2019 15:45 67061600 6 "DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1.;CM-MAC=14:c0:3e:0a:5e:59;CMTS-MAC=58:97:bd:2e:a6:3e;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 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:0a:5e:59;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
11/14/2019 19:40 2436694044 3 "Resetting the cable modem due to docsDevResetNow"
01/01/1970 00:00 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:0a:5e:59;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:02 82000200 3 "No Ranging Response received - T3 time-out;CM-MAC=14:c0:3e:0a:5e:59;CMTS-MAC=58:97:bd:2e:a6:3e;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01 84000100 3 "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=14:c0:3e:0a:5e:59;CMTS-MAC=00:00:00:00:00:00;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=14:c0:3e:0a:5e:59;CMTS-MAC=00:00:00:00:00:00;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=14:c0:3e:0a:5e:59;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"

 

 

 

Here's the modem's STATUS:

 

Connection

The status listed show the connection state of the cable modem. They are used by your service provider to evaluate the operation of the cable modem.

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 723000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed  

 
Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
37 Locked QAM256 723000000 Hz -1.8 dBmV 39.9 dB 0 0
9 Locked QAM256 555000000 Hz -0.4 dBmV 41.4 dB 0 0
10 Locked QAM256 561000000 Hz -0.9 dBmV 41.3 dB 0 0
11 Locked QAM256 567000000 Hz -0.8 dBmV 41.4 dB 0 0
12 Locked QAM256 573000000 Hz -0.3 dBmV 41.4 dB 0 0
13 Locked QAM256 579000000 Hz 0.1 dBmV 41.6 dB 0 0
14 Locked QAM256 585000000 Hz 0.2 dBmV 41.6 dB 0 0
15 Locked QAM256 591000000 Hz -0.1 dBmV 41.2 dB 0 0
16 Locked QAM256 597000000 Hz -0.6 dBmV 41.2 dB 0 0
17 Locked QAM256 603000000 Hz -0.9 dBmV 41.0 dB 0 0
18 Locked QAM256 609000000 Hz -1.6 dBmV 40.8 dB 0 0
19 Locked QAM256 615000000 Hz -0.9 dBmV 41.0 dB 0 0
20 Locked QAM256 621000000 Hz -0.6 dBmV 40.9 dB 0 0
21 Locked QAM256 627000000 Hz -0.4 dBmV 41.0 dB 0 0
22 Locked QAM256 633000000 Hz -0.7 dBmV 40.8 dB 0 0
23 Locked QAM256 639000000 Hz -0.8 dBmV 40.8 dB 0 0
24 Locked QAM256 645000000 Hz -0.8 dBmV 40.7 dB 0 0
25 Locked QAM256 651000000 Hz -0.6 dBmV 40.7 dB 0 0
26 Locked QAM256 657000000 Hz -0.7 dBmV 40.7 dB 0 0
27 Locked QAM256 663000000 Hz -0.8 dBmV 40.7 dB 0 0
28 Locked QAM256 669000000 Hz -1.6 dBmV 40.2 dB 0 0
29 Locked QAM256 675000000 Hz -1.8 dBmV 39.0 dB 0 0
30 Locked QAM256 681000000 Hz -2.1 dBmV 40.2 dB 0 0
31 Locked QAM256 687000000 Hz -1.8 dBmV 40.1 dB 0 0
32 Locked QAM256 693000000 Hz -1.2 dBmV 40.3 dB 0 0
33 Locked QAM256 699000000 Hz -0.9 dBmV 40.2 dB 0 0
34 Locked QAM256 705000000 Hz -1.0 dBmV 40.2 dB 0 0
35 Locked QAM256 711000000 Hz -1.4 dBmV 40.1 dB 0 0
36 Locked QAM256 717000000 Hz -1.7 dBmV 40.0 dB 0 0
38 Locked QAM256 729000000 Hz -1.6 dBmV 40.0 dB 0 0
39 Locked QAM256 735000000 Hz -1.9 dBmV 39.9 dB 0 0
40 Locked QAM256 741000000 Hz -1.7 dBmV 39.9 dB 0 0
159 Locked Other 762000000 Hz -2.0 dBmV 37.5 dB 142501967 0



 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 1 Locked SC-QAM Upstream 35800000 Hz 6400000 Hz 45.0 dBmV
2 2 Locked SC-QAM Upstream 29400000 Hz 6400000 Hz 44.0 dBmV
3 3 Locked SC-QAM Upstream 23000000 Hz 6400000 Hz 44.0 dBmV
4 4 Locked SC-QAM Upstream 16600000 Hz 6400000 Hz 43.0 dBmV



 

Current System Time: Sun Nov 17 16:11:49 2019


 

 

Expert

Re: Arris SB8200 upstream not bound to DOCSIS 3.1 - power levels are too low according to Arris

Comcast does not use DOCSIS 3.1 upstream.

Those upstream are normal and the power figures are normal.

Are you actually having any service issues?

I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Expert

Re: Arris SB8200 upstream not bound to DOCSIS 3.1 - power levels are too low according to Arris

Not sure what the problem is but the signal stats are fine and the modem appears to be provisioned correctly for the gig speed tier because the upload speed is correct. Comcast does not yet offer DOCSIS 3.1 on the upstream, hence you will not see any locked upstream channels.

 

See if anything here applies;

 

https://forums.xfinity.com/t5/Your-Home-Network/Troubleshooting-Gigabit-internet-speeds/m-p/3145413#...



I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!