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High first-hop latency and packet loss

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Frequent Visitor

High first-hop latency and packet loss

Is there something that can be done about high latency and jitter at my first-hop on Comcast's network? I've been noticing this problem nightly for at least a month, where I'll see extreme latency and packet loss at the first hop outside my home. I'm testing using a windows 10 PC that's connected to my firewall with a 1-gig ethernet connection. The same ping to my local firewall is consistent at <1ms latency, so I'm fairly confident it's not contributing to the problem. This is causing problems with applications like remote desktop, which I'm using far more these days (as I assume many are).

 

first hop.png

 

channel power.png

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Expert

Re: High first-hop latency and packet loss

Can't see your pics. Since you are a new poster, they need to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting them at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to them here.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Frequent Visitor

Re: High first-hop latency and packet loss

It looks like my pictures got approved.

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Frequent Visitor

Re: High first-hop latency and packet loss

I just tried contacting Comcast chat support and found that they aren't offering that at this time.

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Expert

Re: High first-hop latency and packet loss

Post the upstream power level numbers as well.



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Frequent Visitor

Re: High first-hop latency and packet loss

upstream power.png

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Expert

Re: High first-hop latency and packet loss

Can't see your latest pic.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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Frequent Visitor

Re: High first-hop latency and packet loss

How about this:

 

https://imgur.com/a/tA91psn

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Expert

Re: High first-hop latency and packet loss

The downstream power is high. Is there an amplifier on the coax line leading to the modem ? If so, try removing it. If not, try using a 3 dB signal attenuator pad like this one on the back of the modem;

 

https://www.amazon.com/In-Line-Attenuator-3-dB-1/dp/B0002ZPIUU

 

You could try a 6 dB one as well. Not certain that this is the direct cause of the problem. YMMV. Good luck !



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Frequent Visitor

Re: High first-hop latency and packet loss

Does anyone from Comcast actually read these forums? I'm wondering if I'm just wasting my time here.

 

I did (finally) get in touch with an agent using chat. He blamed my wireless connection (I'm not using wifi), before providing me this gem:

 

"7:20:03 PM Ann Marie : ’Im sorry that we haven't been able to get the MODEM  working, but after performing [list troubleshooting steps taken] we've determined that the  modem is working and responding to our efforts. "

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Expert

Re: High first-hop latency and packet loss

Have you tried an attenuator ?



I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!