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Arris SB8200

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Authorized Vendor

Re: Arris SB8200

If you send me your CM-MAC via PM I can take a quick look at the upstream side..

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Network Engineer, IP Engineer, Docsis..; the views expressed on this post are mine and do not necessarily reflect the views of my employer..

Gamer.. Living the dream one catastrophe at a time Smiley Happy ..
Regular Contributor

Re: Arris SB8200


EG wrote:

 

 

Also. What do you get with a computer connected directly to the 8200 (no router in the mix) ?


I had an Asus hooked up to my new MB8600 and found through testing direct I was getting the speeds of gig but, the Asus was a bottleneck that capped things off at around 250Mbps.  It's quite possible it's the Asus!

Diamond Problem Solver

Re: Arris SB8200

O/k then so changing the modem didn't cure the problem.. 

 

So the downstream SNR figures look 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 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.

 

Also. What do you get with a computer connected directly to the 8200 (no router in the mix) ?

Regular Visitor

Re: Arris SB8200

I am saying I still only get around 215Mbps downstream. 

Diamond Problem Solver

Re: Arris SB8200

O/k so are you saying that changing the modem did the trick or are you saying that you still have the issue ?? I see that you added the stats now, and they are in spec.

Regular Visitor

Re: Arris SB8200

Is above what you are looking for?

 

 

The technicians plugged directly into the modem to show me the noise. It was crazy. Everything else came out clean. They tested every cable. i was impressed.

Diamond Problem Solver

Re: Arris SB8200

Generally the noise comes from the coax line to the modem, not the modem itself. Changing modem's won't eliminate line noise.

 

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

 

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



Regular Visitor

Arris SB8200

I recently upgraded to Gigabit Internet service in Elk Grove, CA with my own modem, SB8200. The technician said I have a ton of noise on my modem so I bought another one. I am stuck at just around 215Mbps down. I have seen 600Mbps only once. It seems as though I am stuck there. I am getting the correct upload speed, around 40Mbps up. Any advice for me to get around this? I am also running a RT-AC66U for my router with the latest firmware. Thanks!

 

Connection

The status listed show the connection state of the cable modem. They are used by your service provider to evaluate the operation of the cable modem.

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 621000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed  

 
Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
31 Locked QAM256 621000000 Hz 6.7 dBmV 38.8 dB 0 0
1 Locked QAM256 435000000 Hz 4.8 dBmV 38.7 dB 0 0
2 Locked QAM256 441000000 Hz 4.6 dBmV 38.6 dB 0 0
3 Locked QAM256 447000000 Hz 4.6 dBmV 38.7 dB 0 0
4 Locked QAM256 453000000 Hz 4.6 dBmV 38.5 dB 0 0
5 Locked QAM256 459000000 Hz 4.6 dBmV 38.5 dB 0 0
6 Locked QAM256 465000000 Hz 4.4 dBmV 38.4 dB 0 0
7 Locked QAM256 471000000 Hz 4.5 dBmV 38.5 dB 0 0
8 Locked QAM256 477000000 Hz 4.9 dBmV 38.5 dB 0 0
9 Locked QAM256 483000000 Hz 5.0 dBmV 38.4 dB 0 0
10 Locked QAM256 489000000 Hz 5.1 dBmV 38.5 dB 0 0
11 Locked QAM256 495000000 Hz 5.4 dBmV 38.5 dB 0 0
12 Locked QAM256 501000000 Hz 5.3 dBmV 38.2 dB 0 0
13 Locked QAM256 507000000 Hz 5.6 dBmV 38.4 dB 0 0
14 Locked QAM256 513000000 Hz 5.9 dBmV 38.6 dB 0 0
15 Locked QAM256 519000000 Hz 6.3 dBmV 38.7 dB 0 0
16 Locked QAM256 525000000 Hz 6.2 dBmV 38.8 dB 0 0
17 Locked QAM256 531000000 Hz 6.3 dBmV 38.7 dB 0 0
18 Locked QAM256 537000000 Hz 6.5 dBmV 38.8 dB 0 0
19 Locked QAM256 543000000 Hz 6.7 dBmV 38.7 dB 0 0
20 Locked QAM256 549000000 Hz 6.8 dBmV 38.6 dB 0 0
21 Locked QAM256 555000000 Hz 7.2 dBmV 38.8 dB 0 0
22 Locked QAM256 561000000 Hz 7.4 dBmV 38.8 dB 0 0
23 Locked QAM256 567000000 Hz 7.5 dBmV 38.9 dB 0 0
24 Locked QAM256 573000000 Hz 7.6 dBmV 38.9 dB 0 0
25 Locked QAM256 579000000 Hz 7.6 dBmV 38.8 dB 0 0
26 Locked QAM256 585000000 Hz 7.9 dBmV 39.0 dB 0 0
27 Locked QAM256 591000000 Hz 7.6 dBmV 39.0 dB 0 0
28 Locked QAM256 597000000 Hz 7.5 dBmV 39.0 dB 0 0
29 Locked QAM256 603000000 Hz 7.2 dBmV 38.8 dB 0 0
30 Locked QAM256 615000000 Hz 6.8 dBmV 38.8 dB 0 0
33 Locked Other 675000000 Hz 7.2 dBmV 37.5 dB 3356962 0

 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 1 Locked SC-QAM 17300000 Hz 6400000 Hz 37.5 dBmV
2 2 Locked SC-QAM 23700000 Hz 6400000 Hz 37.3 dBmV
3 3 Locked SC-QAM 30300000 Hz 6400000 Hz 37.8 dBmV
4 4 Locked SC-QAM 36700000 Hz 6400000 Hz 39.0 dBmV

 

Current System Time: Wed Jan 10 15:15:49 2018

 

Time Priority Description
1-1-1970, 0:0:39 Notice(6) "Honoring MDD; IP provisioning mode = IPv6"
1-1-1970, 0:0:33 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=b0:da:f9:2b:52:c9;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:28 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=b0:da:f9:2b:52:c9;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
1-1-1970, 0:0:33 Critical(3) "Telnet user logged in from IP address 192.168.100.10."
1-1-1970, 0:0:29 Critical(3) "SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=b0:da:f9:2b:52:c9;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"