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Upstream issues.

Contributor

Upstream issues.

It is back again. I had this issue when I first moved into my new home. The dbs was too high so they added a splitter and I also had some bad wiring due to animals chewing the line. I had something called a block changed outside. Anyway the issue is back. I could be playing a game online, streaming etc and out of the blue I’m disconnected. I check modem and my upstream is blinking. I called Comcast and told them I had this issue once before. Well he came out said everything looks fine and left. He was here a total of 5 minutes. He said it was due to hurricane Irma but this issue started before the storm and has gotten worse. I’ll post a picture of my modem stats so you all can help me. Thank you.
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Contributor

Re: Upstream issues.

Would my Uncorrectables have anything to do with it? Could I have some inference somewhere? Bad cables?
Expert

Re: Upstream issues.

That amount is small but it depends on the total uptime of the modem.

 

The stats as read at the modem level at that moment in time were o/k but there are three additional signal stats that can cause problems 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 Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream 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.