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Random and Constant Connection Timeout

Regular Visitor

Random and Constant Connection Timeout

I'm often having my internet connection cut out for a split second during random times of the day. It will occure multiple times a day. Seeing as it only lasts a second, most people wouldn't see this as a problem. However, as I am trying to be a consistent live streamer, it's quite annoying to hear my live stream cut out multiple times within a couple hours. I know that it is not my streaming program because my game and other internet related services get cut from the network as well. I've streamed during busy and non-busy hours but the problem still resides. Even while I'm not streaming my connection will cut out on me every now and again.

 

I've read on a seperate thread that poor cables and splitters can cause this to happen.

http://forums.xfinity.com/t5/Basic-Internet-Connectivity-And/Intermittent-Connection-Issues/m-p/2665...

However, we've already had a Comcast technician come in and replace them all.

An interesting thing that happens after my connection cuts out is the speedtest results. My recorded speeds are half of what I am paying for. This only lasts for about 5 minutes before returning to normal.

 

 

Expert

Re: Random and Constant Connection Timeout

Start with the modem's signal stats. Perhaps they already are, or they are close to being out of spec and intermittently they go completely of spec. 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 ?

Is this a WiFi connection ?

Regular Visitor

Re: Random and Constant Connection Timeout

SB6183 Modem, on a wired connection. We just recovered from a neighborhood outage.

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables
1 Locked QAM256 2 519000000 Hz 4.3 dBmV 37.4 dB 0 0
2 Locked QAM256 3 525000000 Hz 4.4 dBmV 37.6 dB 0 0
3 Locked QAM256 4 531000000 Hz 3.9 dBmV 37.4 dB 0 0
4 Locked QAM256 5 537000000 Hz 4.0 dBmV 37.5 dB 0 0
5 Locked QAM256 6 543000000 Hz 4.0 dBmV 37.3 dB 0 0
6 Locked QAM256 7 549000000 Hz 3.8 dBmV 37.2 dB 0 0
7 Locked QAM256 8 555000000 Hz 3.6 dBmV 37.1 dB 0 0
8 Locked QAM256 9 561000000 Hz 3.7 dBmV 37.2 dB 0 0
9 Locked QAM256 10 567000000 Hz 3.6 dBmV 37.3 dB 0 0
10 Locked QAM256 11 573000000 Hz 3.6 dBmV 37.3 dB 0 0
11 Locked QAM256 13 585000000 Hz 4.0 dBmV 37.3 dB 0 0
12 Locked QAM256 14 591000000 Hz 3.7 dBmV 37.2 dB 0 0
13 Locked QAM256 15 597000000 Hz 3.4 dBmV 37.2 dB 0 0
14 Locked QAM256 16 603000000 Hz 3.2 dBmV 37.1 dB 0 0
15 Locked QAM256 17 615000000 Hz 2.5 dBmV 37.0 dB 0 0
16 Locked QAM256 20 633000000 Hz 1.3 dBmV 36.5 dB 0 0
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 23 5120 Ksym/sec 30300000 Hz 46.0 dBmV
2 Locked ATDMA 21 2560 Ksym/sec 18900000 Hz 45.5 dBmV
3 Locked ATDMA 22 5120 Ksym/sec 23700000 Hz 45.3 dBmV
4 Locked ATDMA 24 5120 Ksym/sec 36700000 Hz 45.5 dBmV

Current System Time: Tue Dec 29 16:13:03 2015

 

Expert

Re: Random and Constant Connection Timeout

The stats as read at the modem level at that moment in time were good but there are three additional signal stats which can't be read by the modem. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.

They are the 'Upstream Receive Power Level', the 'uSNR' (upstream Signal To Noise Ratio), and the "ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.

You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -2dB to +2dB with 0dB being in the middle and perfect.

The Upstream SNR should be least 31dB, and the higher it is the better.

The ICFR should be no higher than 2 dB.

You could have an intermittent noise ingress issue in only the upstream channel(s) / return path only somewhere.

They will be able to see whether or not everything is in the green zone and also see a history plot for the modem. 

Regular Visitor

Re: Random and Constant Connection Timeout

So I have to contact Comcast support and ask for those readings?

Expert

Re: Random and Constant Connection Timeout

Yep. And hope that you get a rep that knows what they are doing / how to query for them. Good luck !

Regular Visitor

Re: Random and Constant Connection Timeout

They were only able to give me my uSNR.

SNR Up26.1 dBmV

Expert

Re: Random and Constant Connection Timeout

It's out of spec. As stated, it should be a minimum of 31 dB. You should get a tech back out to investigate and correct. Good luck !

Regular Visitor

Re: Random and Constant Connection Timeout

Tech came over and told me some new information that the 3+ support reps didn't tell me.

If you have residential service then you actually have an upload cap. The upload bandwidth is reserved for their buisness services since they don't expect residentual homes to be using so much. 

 

Some back-up information is that I've talked with livestreamers who are well known and use xfinity. They had to upgrade to buisness class services to get a stable connection.

 

There should probably be a pinned thread stating that if your download speeds are normal, but your upload speeds take a dump, then it's on comcasts side. Their speed experience doesn't report data cap throttles.

 

(I do not live in a data cap area, but the upload cap is on every residential service)

Expert

Re: Random and Constant Connection Timeout


ShikuTeshi wrote:

Tech came over and told me some new information that the 3+ support reps didn't tell me.

If you have residential service then you actually have an upload cap. The upload bandwidth is reserved for their buisness services since they don't expect residentual homes to be using so much. 

 

That is not true, sorry. He's just talkin' karp.

 

Some back-up information is that I've talked with livestreamers who are well known and use xfinity. They had to upgrade to buisness class services to get a stable connection.

 

The business class service uses the exact same infrastructure / hardware / lines as the residential service. There is no priority bandwidth or QOS of any kind. Business class just offers a faster response time for tech visits in the case of outages / service problems.

  

(I do not live in a data cap area, but the upload cap is on every residential service)

 

Again. This is simply not so...


 

Expert
Moved:

Re: Random and Constant Connection Timeout

Two year old dead thread thread now being closed. Miss-located post moved to the *e-mail* help board.