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DOCSIS 3.1 Gigabit Tier Speeds -- no D/L speed benefit?

Regular Visitor

DOCSIS 3.1 Gigabit Tier Speeds -- no D/L speed benefit?

Over the weekend I saw that gigabit cable service had become available in my neighborhood.  I bought a DOCSIS 3.1 modem (the Arris 8200), replaced the modem first, then later upgraded the service.  My gateway performs periodic speed tests, and here's what the chart for the last two weeks looks like:

SpeedTest.jpg

 

 

 

 

 

 

 

 

 

 

My upload speed (purple) is more stable at the higher speed, which I appreciate, but the download speed (green) is not only on average no faster than my previous service, but the speed is much less stable than it was prior to the upgrade, which really translates to a net degredation of my prior 300Mbit service.  The modem has been restarted since the upgrade (that drop early in the AM of the 4th is a restart).  

 

I'm not sure what else to try here, but I definitely would have expected performance after the upgrade to be at worst identical (if, say, I've hit a limit of what my on-site wiring can support, which should not be the case), but instead I'm getting the same speed with a larger standard deviation.  What gives?  What can I do to fix this and get at least in the neighborhood of the upgrade I've paid for?

Authorized Vendor

Re: DOCSIS 3.1 Gigabit Tier Speeds -- no D/L speed benefit?

Can you post your channel signals and logs..  Please remove your CM-MAC from the post..

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Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
Regular Visitor

Re: DOCSIS 3.1 Gigabit Tier Speeds -- no D/L speed benefit?

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 687000000 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
31 Locked QAM256 687000000 Hz 7.0 dBmV 41.6 dB 0 0
1 Locked QAM256 507000000 Hz 5.0 dBmV 41.2 dB 0 0
2 Locked QAM256 513000000 Hz 5.1 dBmV 41.1 dB 0 0
3 Locked QAM256 519000000 Hz 5.2 dBmV 41.0 dB 0 0
4 Locked QAM256 525000000 Hz 5.2 dBmV 40.9 dB 0 0
5 Locked QAM256 531000000 Hz 5.5 dBmV 41.1 dB 0 0
6 Locked QAM256 537000000 Hz 5.7 dBmV 41.3 dB 0 0
7 Locked QAM256 543000000 Hz 5.8 dBmV 41.4 dB 0 0
8 Locked QAM256 549000000 Hz 6.1 dBmV 41.4 dB 0 0
9 Locked QAM256 555000000 Hz 6.2 dBmV 41.6 dB 0 0
10 Locked QAM256 561000000 Hz 6.4 dBmV 41.6 dB 0 0
11 Locked QAM256 567000000 Hz 6.4 dBmV 41.7 dB 0 0
12 Locked QAM256 573000000 Hz 6.5 dBmV 41.6 dB 0 0
13 Locked QAM256 579000000 Hz 6.4 dBmV 41.6 dB 0 0
14 Locked QAM256 585000000 Hz 6.7 dBmV 41.7 dB 0 0
15 Locked QAM256 591000000 Hz 6.7 dBmV 41.7 dB 0 0
16 Locked QAM256 597000000 Hz 6.8 dBmV 41.6 dB 0 0
17 Locked QAM256 603000000 Hz 6.7 dBmV 41.7 dB 0 0
18 Locked QAM256 609000000 Hz 6.8 dBmV 41.7 dB 0 0
19 Locked QAM256 615000000 Hz 6.8 dBmV 41.6 dB 0 0
20 Locked QAM256 621000000 Hz 6.9 dBmV 41.5 dB 0 0
21 Locked QAM256 627000000 Hz 6.7 dBmV 41.5 dB 0 0
22 Locked QAM256 633000000 Hz 6.6 dBmV 41.5 dB 0 0
23 Locked QAM256 639000000 Hz 6.6 dBmV 41.5 dB 0 0
24 Locked QAM256 645000000 Hz 6.7 dBmV 41.4 dB 0 0
25 Locked QAM256 651000000 Hz 6.8 dBmV 41.6 dB 0 0
26 Locked QAM256 657000000 Hz 6.7 dBmV 41.8 dB 0 0
27 Locked QAM256 663000000 Hz 6.9 dBmV 41.6 dB 0 0
28 Locked QAM256 669000000 Hz 6.9 dBmV 41.7 dB 0 0
29 Locked QAM256 675000000 Hz 6.9 dBmV 41.5 dB 0 0
30 Locked QAM256 681000000 Hz 7.1 dBmV 41.7 dB 0 0
33 Locked Other 822000000 Hz 9.2 dBmV 40.0 dB 517 0
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 10 Locked SC-QAM 30100000 Hz 6400000 Hz 40.0 dBmV
2 9 Locked SC-QAM 36500000 Hz 6400000 Hz 39.8 dBmV
3 11 Locked SC-QAM 23700000 Hz 6400000 Hz 39.3 dBmV
4 12 Locked SC-QAM 17300000 Hz 6400000 Hz 39.0 dBmV
Current System Time: Mon Mar 5 23:04:05 2018

 

Event Log
The table below contains the log of events that the SB8200 has detected. This log can be important to the service provider to help diagnose and correct problems, if any should occur.
Time Priority Description
3-4-2018, 21:40:0 Critical(3) "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:01:5c:63:f2:5f;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:43 Notice(6) "Honoring MDD; IP provisioning mode = IPv6"
1-1-1970, 0:0:38 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:01:5c:63:f2:5f;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:33 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
3-4-2018, 0:37:42 Critical(3) "Resetting the cable modem due to docsDevResetNow"
1-1-1970, 0:0:38 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:01:5c:63:f2:5f;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:33 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
3-4-2018, 0:24:26 Critical(3) "Resetting the cable modem due to docsDevResetNow"
1-1-1970, 0:0:38 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:01:5c:63:f2:5f;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:33 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
3-3-2018, 22:36:10 Critical(3) "Resetting the cable modem due to docsDevResetNow"
1-1-1970, 0:0:38 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:01:5c:63:f2:5f;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:33 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:1:59 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:01:5c:63:f2:5f;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:1:55 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:28 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:32 Critical(3) "Telnet user logged in from IP address 192.168.100.10."
1-1-1970, 0:0:28 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX:XX:XX;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"