Community Forum

Bonded Download Channels

Clifford1234
Frequent Visitor

Bonded Download Channels

Just trying to determine how many bonded download channels are available in my area. Current modem is having issues and I want to make sure the replacement that I purchase takes advantage of what's available. Can anyone point me in the right direction? So far, customer service hasn't been able to assist me and/or put me in touch with the right personnel that can help. Thank you.

cxrider
Regular Contributor

Re: Bonded Download Channels

I wouldn't be concerned so much about the number of download channels in your area as I would be about getting a modem that is compatible with Comcast/Xfinity.    I personally would suggest being forward thinking and getting a modem that is also DOSCIS 3.1 compliant.    DOSCIS 3.1 supports download speeds up to 10Gb.   My old SB6121 is a 4x4 with a maxium download speed of 172 Mb/s.  An 8x32 modem should cover all offerings in your area with maybe the exception of 1Gb and I think that is only becuase the 1Gb requires special equipment.   I see a $500 equipment fee for 1Gb service in my area so that makes me think service may be optical.   I know my 8x32 modem is using all download channels yet my service plan is only 100Mb/s.    

 

Look at the offerings in your area, decide on what you want today as a service plan, what you will want in the future, and plan accordingly.    Even if your area has less than 32 download channels, and I doubt that's the case, I suspect all areas have 32 channels unless they are serviced by really old equipment, getting an 8x32 will work for you.   If you never, ever see wanting more than 500-600 Mb/s you can go with 8x24.

EG
Expert

Re: Bonded Download Channels


@Clifford1234 wrote:

 Current modem is having issues .


How do you know it's the modem ? Maybe it's the connection to the system ?

 

Please describe the "issues" that you are having.

 

What do the modem's signal stats look like ? 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 there a router / WiFi in the mix ? 

 

 



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EG
Expert

Re: Bonded Download Channels


@cxrider wrote:

 DOSCIS 3.1 supports download speeds up to 10Gb.   

 

Yes but Comcast currently offers only a single 192 MHz  / DOCSIS 3.1 / OFDM modulated downstream channel which has a 1.89 Gigabit throughput capability, but they currently offer only a 1 Gigabit speed tier. Me thinks that it will be a long long time (if ever) before they ever free up / have enough of an RF frequency spectrum to be able to deliver 10 Gig.

 

An 8x32 modem should cover all offerings in your area with maybe the exception of 1Gb and I think that is only becuase the 1Gb requires special equipment.  

 

Comcast will only deliver the 1 Gigabit speed tier via the DOCSIS 3.1 / OFDM modulated downstream channel, not via the multiple bonded QAM 256 modulated channels, although having enough of them bonded together are theoretically capable.

 

I see a $500 equipment fee for 1Gb service in my area so that makes me think service may be optical.

 

1 Gigabit is not optical fiber, it's DOCSIS / coax. Their "Gigabit Pro" (2 gigabit) service offering is delivered via FTTH (Fiber To The Home).

 

I suspect all areas have 32 channels 

 

Many areas that have upgraded their system to DOCSIS 3.1 are now offering only 31 bonded QAM 256 / DOCSIS 3.0 downstream channels.

 

DOCSIS 4.0 / full duplex is on the horizon.


 



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Xephyr
New Poster

Re: Bonded Download Channels

@EG ,

 

Quick question. if 1gbps is delievered using the OFDM downloaded channel. what are those 32 QAM256 channels for. Reason I ask is because I see that my modem only locks 10 QAM256 channels and the rest of the frequencies are simply not locked. I tried several ways to make sure I remove unnecessary splitters, connections to have enough signals...etc. One time I log in after an hours or so I saw 22 locked QAM256 channels. While i don't see any performance difference (940 Download/40 upload on wired LAN), I do wonder why sometimes it has more channels. Also one time I set the starting frequency to the lowest of the 10 usually locked frequencies, once modem reboot, it started with 22 lockec QAM256 cannels. Just wondering if that's normal. 

 

Thank you very much for clarification!

 

And the reason i started to check these is because my modem sometimes drops packets and Netflix starts to show me 0.3mpbs low-res videos... and sometimes completely stops, until I reboot the modem. Started at once a month to once a week, and recently several times a day. (and mostly Friday and weekends seems like more often.) After removing some splitters and connect more direcly cable modem to the incoming coaxial cable, the 4 upstream power dropped from 50dBmv to around 41.3dBmv. Hopefully this solve the intemittnent connection package drop problem.

 

 

Below is my Netgear CM1200 channel status. 

 

Startup Procedure
ProcedureStatusComment
Acquire Downstream Channel561000000 HzLocked
Connectivity StateOKOperational
Boot StateOKOperational
SecurityEnabledBPI+
IP Provisioning ModeHonor MDDhonorMdd(4)
 
Downstream Bonded Channels (Partial Service)
ChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables
1LockedQAM25628561000000 Hz-2 dBmV43.2 dB00
2Not LockedUnknown4405000000 Hz0.0 dBmV0.0 dB00
3Not LockedUnknown5411000000 Hz0.0 dBmV0.0 dB00
4Not LockedUnknown6417000000 Hz0.0 dBmV0.0 dB00
5Not LockedUnknown7423000000 Hz0.0 dBmV0.0 dB00
6Not LockedUnknown8429000000 Hz0.0 dBmV0.0 dB00
7Not LockedUnknown9435000000 Hz0.0 dBmV0.0 dB00
8Not LockedUnknown10441000000 Hz0.0 dBmV0.0 dB00
9Not LockedUnknown11447000000 Hz0.0 dBmV0.0 dB00
10Not LockedUnknown12453000000 Hz0.0 dBmV0.0 dB00
11Not LockedUnknown13459000000 Hz0.0 dBmV0.0 dB00
12Not LockedUnknown14465000000 Hz0.0 dBmV0.0 dB00
13Not LockedUnknown15471000000 Hz0.0 dBmV0.0 dB00
14Not LockedUnknown16477000000 Hz0.0 dBmV0.0 dB00
15Not LockedUnknown17483000000 Hz0.0 dBmV0.0 dB00
16Not LockedUnknown18489000000 Hz0.0 dBmV0.0 dB00
17Not LockedUnknown19495000000 Hz0.0 dBmV0.0 dB00
18Not LockedUnknown20507000000 Hz0.0 dBmV0.0 dB00
19Not LockedUnknown21513000000 Hz0.0 dBmV0.0 dB00
20Not LockedUnknown22519000000 Hz0.0 dBmV0.0 dB00
21Not LockedUnknown23525000000 Hz0.0 dBmV0.0 dB00
22Not LockedUnknown24531000000 Hz0.0 dBmV0.0 dB00
23LockedQAM25625543000000 Hz-4.8 dBmV41.7 dB00
24LockedQAM25626549000000 Hz-2.4 dBmV43 dB00
25LockedQAM25627555000000 Hz-2.3 dBmV43.1 dB00
26LockedQAM25629567000000 Hz-1.7 dBmV43.2 dB00
27LockedQAM25630573000000 Hz-1.7 dBmV43.2 dB00
28LockedQAM25631579000000 Hz-2.1 dBmV43.1 dB00
29LockedQAM25632585000000 Hz-2.8 dBmV42.8 dB00
30LockedQAM25633591000000 Hz-3.7 dBmV42.4 dB00
31LockedQAM25634597000000 Hz-4.4 dBmV42 dB00
32Not LockedUnknown00 Hz0.0 dBmV0.0 dB00
 
Upstream Bonded Channels
ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower
1LockedATDMA15120 Ksym/sec16400000 Hz41.3 dBmV
2LockedATDMA25120 Ksym/sec22800000 Hz41.3 dBmV
3LockedATDMA35120 Ksym/sec29200000 Hz41.5 dBmV
4LockedATDMA45120 Ksym/sec35600000 Hz41.3 dBmV
5Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV
 
Downstream OFDM Channels
ChannelLock
Status
Modulation /
Profile ID
Channel
ID
FrequencyPowerSNR /
MER
Active Subcarrier
Number Range
Unerrored
Codewords
Correctable
Codewords
Uncorrectable
Codewords
1Locked0 ,1 ,2 ,348688000000 Hz0.8 dBmV43.5 dB1108 ~ 2987278241900708010040
2Not Locked000 Hz0 dBmV0.0 dB0 ~ 4095000
 
Upstream OFDMA Channels
ChannelLock StatusModulation / Profile IDChannel IDFrequencyPower
1Not Locked000 Hz0 dBmV
2Not Locked000 Hz0 dBmV

 

 

 

 

EG
Expert

Re: Bonded Download Channels


@Xephyr wrote:

@EG ,

 

Quick question. if 1gbps is delievered using the OFDM downloaded channel. what are those 32 QAM256 channels for.

 

All of the other speed tiers / traffic.

 

Reason I ask is because I see that my modem only locks 10 QAM256 channels and the rest of the frequencies are simply not locked. I tried several ways to make sure I remove unnecessary splitters, connections to have enough signals...etc. One time I log in after an hours or so I saw 22 locked QAM256 channels. While i don't see any performance difference (940 Download/40 upload on wired LAN), I do wonder why sometimes it has more channels. Also one time I set the starting frequency to the lowest of the 10 usually locked frequencies, once modem reboot, it started with 22 lockec QAM256 cannels. Just wondering if that's normal. 

 

Thank you very much for clarification!

 

Poor connection quality, noise ingress into the lines somewhere can cause the unbonding of channels.

 

And the reason i started to check these is because my modem sometimes drops packets and Netflix starts to show me 0.3mpbs low-res videos... and sometimes completely stops, until I reboot the modem. Started at once a month to once a week, and recently several times a day. (and mostly Friday and weekends seems like more often.) After removing some splitters and connect more direcly cable modem to the incoming coaxial cable, the 4 upstream power dropped from 50dBmv to around 41.3dBmv. Hopefully this solve the intemittnent connection package drop problem.

 

41 dB of upstream power is right within the desired *sweet spot* of 40 to 45 dB !

 

Please feel free to create a new topic of your own here on this board detailing your issue. 10 month old dead thread now being closed.


 



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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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