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What does "CCAP Commanded Power in Excess of 6 dB Below..." mean?
"RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW" means exactly what? Often seen with "Dynamic Range Window violation" and "Started Unicast Maint...
Finally, after a ton of tech visits, the ultimate problem causing this issue has been found: A bad cable from the top of the telephone pole (at the tap) running 15' to the base of the telephone pole (ground block). For full details (and more), visit: https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
"DRW = Dynamic Range Window
there is a Dynamic Range Window to which CM can adjust power. For e.g. you cannot ask CM to to go from 30dBmV to 50dBmV suddenly. there is a window of 12dB which CM must follow.
basically, CMTS is asking CM to raise beyond DRW and CM is complaining he wont do it.
copied from below website:
https://volpefirm.com/dynamic-range-window-ofdma-troubleshooting/
- DOCSIS 3.0 Dynamic Range Window (DRW)
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During initial ranging on chs being added by TCC encodings, Cable Modem MUST cover entire Dynamic Range Window within 16 retries, leaving no power interval greater than 6 dB untried
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So for DOCSIS 3.0, by commanding power to mid of window it allows to go either 6 dB above or 6 dB below, which will cover whole 12 dB window
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DOCSIS 3.0 uses a per-ch Dynamic Range Window, whereas DOCSIS 3.1 uses a single Dynamic Range Window for all chs in TCC
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DOCSIS 3.0 allows bit more flexibility to shift Dynamic Range Window slightly for each ch if need be
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- DOCSIS 3.1 Dynamic Range Window (DRW)
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CMTS normally administers Dynamic Range Window of 12 dB [DOCSIS MULPIv3.1] which is sufficient to accommodate plant tilts of up to 10 dB from lower to upper edge of US band
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Since fidelity requirements are specified in flat freq conditions from top of Dynamic Range Window, it’s desirable to maintain Cable Modem Tx power levels as close to top of Dynamic Range Window as possible
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DOCSIS 3.1 uses single Dynamic Range Window for all chs in TCC
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Three types of Dynamic Range Window violations reported by BRCM DOCSIS 3.1 Cable Modem"
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Thanks a lot. Yes, already found that (and watched entire video) and actually have been in contact with Brady Volpe.
Also, I have been trying to document everything (and what I learned) as I am going through the process of fixing the issues:
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
I've been getting these same warnings, in my modem's event log file. I'm on Xfinity extreme pro 900mbps, by the way. My modem isn't a Netgear model, but a Motorola MB8600. Power levels on the downstream channels range from +1.4dBmV to -2.8dBmV. I called Xfinity, yesterday, as I've been getting slow speeds for more than a week and got a US tech, rather than someone at their foreign call center. After explaining the problem and the fact that Xfinity's website shows a tech has been working 'in my area' for more than a week, the lady I was speaking with said there is something else definitely wrong with my line and a tech will be coming to look into things, on the 24th. Wish you luck with your problem.
Something you might ask Motorola about as well and see what there take is on that.
Old_Soldier wrote:
I've been getting these same warnings, in my modem's event log file. I'm on Xfinity extreme pro 900mbps, by the way. My modem isn't a Netgear model, but a Motorola MB8600. Power levels on the downstream channels range from +1.4dBmV to -2.8dBmV. I called Xfinity, yesterday, as I've been getting slow speeds for more than a week and got a US tech, rather than someone at their foreign call center. After explaining the problem and the fact that Xfinity's website shows a tech has been working 'in my area' for more than a week, the lady I was speaking with said there is something else definitely wrong with my line and a tech will be coming to look into things, on the 24th. Wish you luck with your problem.
