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bluepoint

join:2001-03-24

4 Bonded Upstream


Upstream
Looks like our division is ready to boogie.


hobgoblin
Sortof Agoblin
Premium
join:2001-11-25
Orchard Park, NY
kudos:11
Welcome to the party!

Hob


Suit Up

join:2003-07-21
Los Angeles, CA
reply to bluepoint
Why is there a mixture of DOCSIS 1/TDMA and DOCSIS 2/ATDMA? Is there a technological advantage to that, or is it because the channels are shared with people who only have DOCSIS 1 modems?


kilrathi
Premium
join:2005-04-22
Rockaway Park, NY
reply to bluepoint
not sure but i have same combination and i am forced to use splitters so that the atdma channels t4 timeout and as soon as that happens i remove splitters and keeps connection working but this way i have no packet loss because in my area the atdma experience interference, the lines here are not ready for it and there is packet loss when I use them. I hope they all running good for you. Although in your case I noticed even atdma running at 16QAM, in my case they try to run 64QAM and it simply too much noise for it.


bluepoint

join:2001-03-24

3 edits
reply to Suit Up
Suit Up See Profile I'm not knowledgeable enough to answer your question as to why TWC chooses those modulations but if you have time read some from »en.wikipedia.org/wiki/Quadrature···dulation I tried to understand what's written at wikipedia but it still doesn't register on this pea brain.
Or DrDrew See Profile or hobs can explain better.


bluepoint

join:2001-03-24

2 edits
reply to kilrathi
Wow kilrathi See Profile, 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 See Profile can give some idea on these things.


CptGemini
Inside your computer
Premium
join:2004-11-29
Corpus Christi, TX
kudos:6
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.
--
»www.akaskriller.com - Your ultimate source for all android needs.


DrDrew
That others may surf
Premium
join:2009-01-28
SoCal
kudos:17
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.
--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.


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).


DrDrew
That others may surf
Premium
join:2009-01-28
SoCal
kudos:17
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.
--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.


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.

horseshoe
Premium
join:2006-10-11
Upland, CA
reply to bluepoint
Stop: I want your Upstream here in So Cal. Stop: I have the Doc 3 modem. Stop: Wait more time. Stop: TWC, want more $?
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 5 5120 Ksym/sec 30700000 Hz 36.9 dBmV
2 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
3 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
4 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV