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Packet loss

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Diamond Problem Solver

Re: Packet loss

@dannyf wrote:
These were levels when the connection is absolutely fine, but I trust you guys there is an issue. Can you tell me which figures are out of spec. I could only see that the downstream snr was slightly low.

Here are the signal ranges;


Specification      Min             Max
Downstream Power Level    
Cable Modems -10dBmV +10dBmV
Gateways and EMTAs -7dBmV +7dBmV
Downstream Signal to Noise Ratio 35dB -
Upstream Power Level +35dBmV +50dBmV
New Poster

Re: Packet loss

These were levels when the connection is absolutely fine, but I trust you guys there is an issue. Can you tell me which figures are out of spec. I could only see that the downstream snr was slightly low.

For info, there is only a single splitter for the cable tv box and that was provided by Comcast during installation. I will try without the splitter and compare levels

Diamond Problem Solver

Re: Packet loss

I already posted a link to the troubleshooting guide pal.............


OP. Your signal stats are borked !!


That can cause random disconnects, spontaneous re-booting of the modem, and speed 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.


Re: Packet loss

Your downstream levels are poor and your upstream levels are considerably outside of specifications. Typically this is caused by bad or substandard wiring/connectors/splitters, but it could be a variety of other issues including bad equipment or an issue on Comcast's end. 

See the troubleshooting guideAlso, has your modem reached End of Life Status?  Check: If you want to schedule a tech visit, let us know and we'll ask an employee to help. 

I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
New Poster

Re: Packet loss

Downstream	         Bonding Channel Value
Channel ID	         1        	2       	3 	        4 
Frequency	         483000000 Hz 	489000000 Hz 	495000000 Hz 	507000000 Hz 
Signal to Noise Ratio	 34 dB 	        34 dB 	        34 dB 	        35 dB 
Downstream Modulation	 QAM256 	QAM256 	        QAM256   	QAM256 
Power Level              -7 dBmV  	-7 dBmV  	-7 dBmV  	-7 dBmV  

Upstream	Bonding Channel Value
Channel ID	3 
Frequency	23000000 Hz 
Ranging Service ID	7904 
Symbol Rate	5.120 Msym/sec 
Power Level	54 dBmV 
Upstream Modulation	[3] QPSK
[3] 64QAM
Ranging Status	Success 

The SnR seems slightly low (linked page says 35dB min).

I'm currently getting 0% packet loss, 88 Mbps down and 12.14 Mbps up. (all good).

Diamond Problem Solver

Re: Packet loss

Post 'em so that we can establish a baseline.

New Poster

Re: Packet loss

The connection was back to normal before I could check the signal levels etc.

They do appear slightly out of the correct ranges, but connection is OK again for now.

Diamond Problem Solver
New Poster

Packet loss

I have extremely poor download speeds (0.7 mbps) and heavy packet loss today.

Computing statistics for 250 seconds...
            Source to Here   This Node/Link
Hop  RTT    Lost/Sent = Pct  Lost/Sent = Pct  Address
  0                                  []
                                0/ 100 =  0%   |
  1    0ms     0/ 100 =  0%     0/ 100 =  0%  DD-WRT []
                                2/ 100 =  2%   |
  2   31ms     9/ 100 =  9%     7/ 100 =  7%  96.x.x.x
                                0/ 100 =  0%   |
  3   33ms    11/ 100 = 11%     9/ 100 =  9%  96.x.x.x
                                0/ 100 =  0%   |
  4   22ms    11/ 100 = 11%     9/ 100 =  9% [96.x.x.x]
                                0/ 100 =  0%   |
  5   27ms     2/ 100 =  2%     0/ 100 =  0% [68.x.x.x]
                                4/ 100 =  4%   |
  6   23ms    11/ 100 = 11%     5/ 100 =  5% [68.x.x.x]
                                0/ 100 =  0%   |
  7   36ms     6/ 100 =  6%     0/ 100 =  0% [23.x.x.x]
                                5/ 100 =  5%   |
  8   47ms    14/ 100 = 14%     3/ 100 =  3%  108.x.x.x
                                0/ 100 =  0%   |
  9  ---     100/ 100 =100%    89/ 100 = 89%  209.x.x.x
                                0/ 100 =  0%   |
 10   48ms    11/ 100 = 11%     0/ 100 =  0% []

Trace complete.

Please can you check for issues in my area?