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Extremely slow upload speeds

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Frequent Visitor

Extremely slow upload speeds

I have recently come into an issue where my upload speed is pretty terrible. This has caused a number of issues for me as i work from home and perform many web conferences etc and need a consistent upload speed to do my job. I currently subscribe for the 300/25 service. My download speed is fantastic, it tests on both speedtest.xfinity.com and other 3rd party sites at or above 300mbps which is great. However, my upload speed is really tanking... i get about 6-8mbps through the xfinity speed test and less than 2mbps through 3rd party sources. This just isn't enough for me to do my job at home. Seeing as i pay for 25mbps i expect i would get at least 15mbps consistently, maybe less during busy hours. I have had a new cable modem, same problem. I had a technician come out and confirm some signal issues outside of the home (but related to the plant). Those issues were supposedly fixed last week - after power cycling all of my equipment i see the same issues with the upload speed. I even bought my own 3.1 docsis cable modem (Arris 8200) and this didn't solve the problem. I was able to do my job and stream data to other sites with no issues up until about 10-12 days ago. Now all my upload speeds are unbarable. I am hoping someonce can help me out. I am going to post some pics of my cable modem and the signals etc. 

Accepted Solution

Re: Extremely slow upload speeds

The issue has been resolved. I have no idea what they did - but a technican comfirmed i was getting some strange signal noise that may be impacting my upload speeds. He opened a plant ticket and said within 24/48 hours i should receive a phone call. I got a call this morning - and after doing an upload speed check i am getting 25/20mbps as expected. Thanks for all your support.

 

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Frequent Visitor

Re: Extremely slow upload speeds

Tests i referenced with the slow upload speed. This is through testmy.net. I know this is a third party site and you can't necessarily rely on this...but this is pretty much accuate in what i am seeing to every single site. I can post twitch based bandwidth tests.

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Authorized Vendor

Re: Extremely slow upload speeds

Going to send you a PM want to check the CMTS side..

-------------------------------------
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 ..
Frequent Visitor

Re: Extremely slow upload speeds

The fact that i can connect to my phone 4g or my hotel wifi and get a better connection than what i am getting through you guys at Xfinity i find just laughable. Especially when i pay the amount of money that i do. If i lived 2 sub divisions over i could get gig speeds for half the cost. Whatever has happened to the network in my area (and i notice the guy above goes through some of the same backbones in your network as me) is causing problems. Again - this isn't a download speed problem - this is purely an UPLOAD speed issue. I would be happy getting less than 100mbps (even though i pay for 300) down if i could just get my upload speed even 50% of the way towards what i pay for (25mbps). 

Frequent Visitor

Re: Extremely slow upload speeds

Running the same test i get similar results - not as much packet loss, but some....

 

|------------------------------------------------------------------------------------------|
|                                      WinMTR statistics                                   |
|                       Host              -   %  | Sent | Recv | Best | Avrg | Wrst | Last |
|------------------------------------------------|------|------|------|------|------|------|
|                             192.168.1.1 -    0 |   87 |   87 |    0 |    0 |    8 |    0 |
|                             96.120.26.5 -    3 |   79 |   77 |    7 |   11 |   26 |    7 |
|                           68.85.208.113 -    3 |   79 |   77 |    7 |   11 |   26 |    8 |
|                          162.151.37.113 -    0 |   87 |   87 |    7 |   10 |   26 |    8 |
|be-124-ar01.elmhurst.il.chicago.comcast.net -    3 |   79 |   77 |    9 |   13 |   27 |   11 |
|be-33491-cr01.chicago.il.ibone.comcast.net -    3 |   79 |   77 |   10 |   15 |   28 |   15 |
|be-10506-cr02.350ecermak.il.ibone.comcast.net -    2 |   83 |   82 |   10 |   13 |   20 |   12 |
|be-10563-pe01.350ecermak.il.ibone.comcast.net -    2 |   83 |   82 |   10 |   12 |   18 |   11 |
|as40428-2-c.11greatoaks.ca.ibone.comcast.net -    3 |   79 |   77 |   10 |   13 |   28 |   15 |
|                   No response from host -  100 |   18 |    0 |    0 |    0 |    0 |    0 |
|                          216.239.42.154 -    3 |   79 |   77 |   12 |   18 |   33 |   17 |
|                           209.85.249.73 -    2 |   83 |   82 |   10 |   12 |   22 |   10 |
|              ord31s22-in-f238.1e100.net -    3 |   79 |   77 |   10 |   14 |   28 |   15 |
|________________________________________________|______|______|______|______|______|______|
   WinMTR v0.92 GPL V2 by Appnor MSP - Fully Managed Hosting & Cloud Provider

Frequent Visitor

Re: Extremely slow upload speeds

Here are my CM logs from the last ~12 hours:

 

3-10-2018, 10:43:17 Warning(5) "MDD message timeout;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-10-2018, 10:26:11 Critical(3) "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 14:31:42 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 14:31:3 Warning(5) "MDD message timeout;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 14:30:52 Critical(3) "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 13:8:23 Warning(5) "TEK Invalid - Invalid Key Sequence Number;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 12:49:39 Critical(3) "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:1:21 Notice(6) "Honoring MDD; IP provisioning mode = IPv6"
1-1-1970, 0:1:7 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 9:38:14 Critical(3) "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 9:2:2 Critical(3) "No Ranging Response received - T3 time-out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 8:59:2 Critical(3) "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 8:58:22 Critical(3) "SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
3-9-2018, 8:57:40 Critical(3) "Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:01:5c:83:58:4d;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:4:26 Critical(3)

"SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=2c:95:69:66:b3:9d;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"

 

 

Here is my cable modem stats page:

 

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 513000000 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
1 Locked QAM256 513000000 Hz 6.8 dBmV 36.6 dB 83677 60080
2 Locked QAM256 519000000 Hz 6.8 dBmV 36.8 dB 96177 20272
3 Locked QAM256 525000000 Hz 6.9 dBmV 36.8 dB 78367 12854
4 Locked QAM256 531000000 Hz 6.9 dBmV 36.7 dB 57557 11087
5 Locked QAM256 537000000 Hz 7.1 dBmV 36.9 dB 32095 10590
6 Locked QAM256 543000000 Hz 6.9 dBmV 36.8 dB 27568 10451
7 Locked QAM256 549000000 Hz 7.0 dBmV 36.8 dB 16044 10598
8 Locked QAM256 555000000 Hz 7.0 dBmV 36.7 dB 14730 10934
9 Locked QAM256 561000000 Hz 6.9 dBmV 36.7 dB 13555 11095
10 Locked QAM256 567000000 Hz 7.1 dBmV 36.9 dB 6752 10384
11 Locked QAM256 573000000 Hz 7.1 dBmV 37.0 dB 7380 9915
12 Locked QAM256 579000000 Hz 7.1 dBmV 37.0 dB 6422 10956
13 Locked QAM256 585000000 Hz 7.1 dBmV 36.9 dB 6321 11298
14 Locked QAM256 591000000 Hz 7.1 dBmV 36.8 dB 6836 10677
15 Locked QAM256 597000000 Hz 7.1 dBmV 36.8 dB 6589 11147
16 Locked QAM256 603000000 Hz 7.1 dBmV 36.8 dB 6684 11543
17 Locked QAM256 609000000 Hz 7.0 dBmV 36.8 dB 7593 11445
18 Locked QAM256 615000000 Hz 7.0 dBmV 36.8 dB 6103 11278
19 Locked QAM256 621000000 Hz 6.8 dBmV 37.0 dB 5756 10916
20 Locked QAM256 627000000 Hz 6.7 dBmV 36.8 dB 6409 10948
21 Locked QAM256 633000000 Hz 6.4 dBmV 36.7 dB 6527 10331
22 Locked QAM256 639000000 Hz 6.3 dBmV 36.6 dB 6576 10157
23 Locked QAM256 645000000 Hz 6.6 dBmV 36.8 dB 4557 11109
24 Locked QAM256 651000000 Hz 6.6 dBmV 36.8 dB 4755 11002
26 Locked QAM256 657000000 Hz 6.5 dBmV 36.7 dB 4198 11215
27 Locked QAM256 663000000 Hz 6.5 dBmV 36.8 dB 4404 11556
28 Locked QAM256 669000000 Hz 6.4 dBmV 36.9 dB 3904 11179
29 Locked QAM256 675000000 Hz 6.5 dBmV 36.6 dB 6318 11014
25 Locked Other 750000000 Hz 7.6 dBmV 35.2 dB 126544 0

 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 60 Locked SC-QAM 16600000 Hz 6400000 Hz 32.8 dBmV
2 57 Locked SC-QAM 35800000 Hz 6400000 Hz 35.8 dBmV
3 58 Locked SC-QAM 29400000 Hz 6400000 Hz 35.0 dBmV
4 59 Locked SC-QAM 23000000 Hz 6400000 Hz

34.0 dBmV

 

Does anyone have any thoughts on this? I am still seeing the issue with terrible upload speeds - the download speeds are just fine. Any statistics or logs here jump out at you as a problem? My upload power is at or lower than the minimum power levels - that is all i can tell that might be slightly off. 

 

Thanks!

Cable Expert

Re: Extremely slow upload speeds

Is your modem connected to a splitter? If so what size splitter?




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Frequent Visitor

Re: Extremely slow upload speeds

It was connected to a splitter when i had TV service as well. Since canceling i have seen this issue pretty much. I have since removed the splitter and now i have the cable in from outside directly connected to the cable modem. There are zero splitters between the outside->inside->cable modem.

 

Thanks

Highlighted
Frequent Visitor

Re: Extremely slow upload speeds

The issue has been resolved. I have no idea what they did - but a technican comfirmed i was getting some strange signal noise that may be impacting my upload speeds. He opened a plant ticket and said within 24/48 hours i should receive a phone call. I got a call this morning - and after doing an upload speed check i am getting 25/20mbps as expected. Thanks for all your support.

 

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