2 edits | reply to kilrathi
Re: 4 Bonded Upstream Wow kilrathi  , it looks like you have wiring problem somewhere. I've seen around you've been on top of your problem and TWC hasn't solve the mystery?
AFAIC, we have a steady/stable connections, in fact, since I acquired the docsis 3 modem, the upstream power got better. When I had the docsis 2 modem(single channel), my upstream power would go from 46 to 55dBmV depending on the freq. The lower the frequency the higher the power. But now with the docsis 3 all 4 channels are about in low power ranges, and sometimes the lowest frequency registers with a better reading. I was told lower frequency uses higher power but now it seems not to support that theory. What do I know anyway? 
As to why we use 16QAM for the upstream, I want to know also. Maybe DrDrew can give some idea on these things. |
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 CptGeminiInside your computerPremium
join:2004-11-29
Corpus Christi, TX
kudos:6
 ·RoadRunner Cable
| My guess would be that its a way to help distribute the bandwidth across the channels better so it don't hog up all bandwidth on those channels for D2/D1 modem users.
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»www.akaskriller.com - Your ultimate source for all android needs. |
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 DrDrewSo that others may surf.
join:2009-01-28
SoCal
kudos:8 | reply to bluepoint
16QAM is used for better noise handling... it can get away with SNR being 6dB (4x) lower than QAM64. The trade off is it has 2/3s the bandwidth per hz.
DOCSIS 1 channels are used for legacy devices... like some older ADSG cable boxes and power supply status monitoring.
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If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes. |
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 Suit Up
join:2003-07-21
Los Angeles, CA | Ah. Thanks for the info DrDrew. Funny you say DOCSIS 1 is for legacy devices, my DOCSIS 2.0 modem still uses a DOCSIS 1 upstream (although it did have DOCSIS 2.0 for a couple of days a week or 2 ago). |
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DrDrewSo that others may surf.
join:2009-01-28
SoCal
kudos:8 | said by Suit Up:Ah. Thanks for the info DrDrew. Funny you say DOCSIS 1 is for legacy devices, my DOCSIS 2.0 modem still uses a DOCSIS 1 upstream (although it did have DOCSIS 2.0 for a couple of days a week or 2 ago).
DOCSIS 3 and 2 can still use DOCSIS 1 channels... why shouldn't they? It's all usable bandwidth.
It's just DOCSIS 1 devices can't use DOCSIS 2 channels. They're not able to tune to 6.4 Mhz wide channels or decode ABOVE 16QAM modulation.
If no DOCSIS 1 channels are available, a DOCSIS 1 device can't get online.
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If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes. |
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Suit Up
join:2003-07-21
Los Angeles, CA | Oh I understand all that, I just think it's amusing you used the term "legacy" when my modem (which I've had probably about 6 months now) is still using it. |
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