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Internet throttling

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Internet throttling

Before the pandemic, I was having issues with speed. I'm paying for Blast! On speed tests (Xfinity ones), I was getting 4-5 Mbps! DURINGthe pandemic (about mid-March into April) I was finally getting 'decent speed' about 40-45 Mbps. NOW, I'm back down to 5-6 Mbps.  

AND my upload light on my (new)cable modem is constantly blinking (and it has 8! upload channels). What gives here? Why did I gat decent speed for a few weeks then get dropped down again? I really don't like being throttled back for what I'm paying. You're making other businesses look better and my non-Xfinity friends telling me to change...they're not having those problems. after beug a GIID customer for OVER 35 years, I should have better service.....

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Expert

Re: Internet throttling

What do the modem's signal stats look like ? Try getting them here http://192.168.100.1 or here http://10.0.0.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.

What is the exact make and model number of the modem ?




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Re: Internet throttling

 

My new cable modem is a Netgear Nighthawk AC1900 C7000v2

 

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 13 507000000 Hz 1 dBmV 38.4 dB 0 0
2 Locked QAM256 17 531000000 Hz 1.4 dBmV 39.1 dB 1 0
3 Locked QAM256 18 537000000 Hz 1.1 dBmV 38.9 dB 3 0
4 Locked QAM256 19 543000000 Hz 1 dBmV 38.7 dB 3 0
5 Locked QAM256 20 549000000 Hz 0.7 dBmV 38.9 dB 1 0
6 Locked QAM256 21 555000000 Hz 1.1 dBmV 37.8 dB 1 0
7 Locked QAM256 22 561000000 Hz 0.9 dBmV 37.5 dB 5 0
8 Locked QAM256 23 567000000 Hz 0.9 dBmV 39 dB 8 0
9 Locked QAM256 24 573000000 Hz 1 dBmV 38.9 dB 16 0
10 Locked QAM256 1 429000000 Hz 0.8 dBmV 39.3 dB 11 0
11 Locked QAM256 2 435000000 Hz 1.2 dBmV 39.1 dB 0 0
12 Locked QAM256 3 447000000 Hz 1.4 dBmV 39.3 dB 0 0
13 Locked QAM256 4 453000000 Hz 1.2 dBmV 39.3 dB 0 0
14 Locked QAM256 5 459000000 Hz 0.9 dBmV 39.2 dB 21 0
15 Locked QAM256 6 465000000 Hz 0.5 dBmV 39.1 dB 7 0
16 Locked QAM256 7 471000000 Hz 0.5 dBmV 39.3 dB 14 0
17 Locked QAM256 8 477000000 Hz -0.2 dBmV 39 dB 0 0
18 Locked QAM256 9 483000000 Hz -0.2 dBmV 39 dB 0 0
19 Locked QAM256 10 489000000 Hz -0.2 dBmV 39.1 dB 0 0
20 Locked QAM256 11 495000000 Hz -0.4 dBmV 39 dB 0 0
21 Locked QAM256 12 501000000 Hz 0 dBmV 39 dB 0 0
22 Locked QAM256 14 513000000 Hz -0.5 dBmV 38.5 dB 0 0
23 Locked QAM256 15 519000000 Hz -0.4 dBmV 38.5 dB 0 0
24 Locked QAM256 16 525000000 Hz -0.4 dBmV 38.2 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 3 5120 Ksym/sec 23000000 Hz 53 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35800000 Hz 54 dBmV
3 Locked ATDMA 2 5120 Ksym/sec 29400000 Hz 54 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 16600000 Hz 53 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
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Expert

Re: Internet throttling

The upstream power is too high / out of spec. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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Re: Internet throttling

Comcast says they do not throttle any more. I have strong circumstantial evidence that they are still throttling. I subscribe to Blast service and have for several years.

 

On Sept 1 and 2 this year I was getting only about 10 Mbps download according to speedtest.net (14 different runs over the two days). I did not test it before then, but the service had deteriorated about a week prior and I finally thought to do a speed check. On Sept 3, which was the start of my next month's bill, it was back to ~80 Mbps and is there again today, Sept 4, as well. This is using various servers around the Seattle area.

 

So much for Comcast saying they do not throttle. I am a remote worker (as are many of us these days) and this has interfered with me being able to participate in Zoom company meetings and other work. We just switched our mobile phone service to Xfinity and now I wonder if that was a good idea.