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[Ixel]

I think the definition of ES does include more than just CRCs:
Also, I don't think it's possible for the DSLAM to get a different downstream ES count apart from what your modem tells it. These things are measured or counted at the end that's receiving the signal, so for the downstream, that's your modem. If the DSLAM wants to know the downstream ES or CRC count, it has to ask your modem to send it the numbers.

I still think HEC errors are not applicable to PTM - there are no ATM headers present.

Ah, I see, that makes sense. Thanks. I started to search for the SEF error counter and I found the counter. Errored seconds may therefore be correct after all and I may have been wrong.

Code: [Select]

Tx_CRC[0]  = 3
Tx_FEC[0]  = 29
Tx_ERR_SEC = 3
Tx_FEC_SEC = 9
Rx_CRC[0]  = 56
Rx_FEC[0]  = 62686414
Rx_ERR_SEC = 29
Rx_FEC_SEC = 26214
Near-end total: los=0, sef=18, lpr=0
Far-end  total: los=1, sef=3, lpr=0
VDSL2 Sync-Up Time:  0 Day(s)  7:16:54

[Ixel]

Since I didn't have much to report for a while I haven't posted. My findings so far is that bitswap appears to not be responsible. Under crosstalk conditions in the evening (lots of noise around D2) I've had it running fine.

What's helped me the most so far have been two settings:
- Rx AGC Gain Adjustment
- Tx Power Control

Now that my connection has been reset back to fastpath and no banding I'm going to run the DrayTek for a day or two at 9 dB SNRM target so I can get a rough idea what sync/attainable rate, CRC errors and error seconds I should be aiming for trying to also get on the ASUS while remaining stable.

The last settings I had on the ASUS were recently:
- Rx AGC Gain Adjustment - 30 (custom setting, much less than what the UI offers and involves modifying the 'select' dropdown element via the browser's inspector)
- Tx Power Control - -4 dB

This definitely closely matches the upload sync and attainable rate I had on the DrayTek, but I need more time to determine the downstream side to compare it between the DrayTek and the ASUS.

Suffice to say that the above settings were stable for me on fastpath though I want to fine tune it further if I can. I didn't get SEF errors or other instability, just some CRC errors every so often but well under control.

[Chrysalis]

was it stable and had comparable speeds, if yes then I guess thats good progress

[Ixel]

was it stable and had comparable speeds, if yes then I guess thats good progress

Yes, it appeared to. I will pretty much conclude things by some time next week. Once this is concluded I'll do a final post on what settings I found to work best overall for my line (which should hopefully work for most other lines using this device) and how that compares to my DrayTek Vigor 2860ac. Hopefully I'll have some good news and a successful outcome.

[Ixel]

Just an update to say that I've ordered a regrade back to 80/20 so I can get the full potential out of my line again (currently 40/10).

So far I've managed to keep a stable connection with the DSL-AC68U. I will be connecting the DrayTek Vigor 2860ac again tomorrow to observe what sync rate and error statistics it gets, then the following day I'll reconnect the DSL-AC68U with my settings and have a comparison ready to post most likely on Tuesday.

My current settings on the DSL-AC68U:

http://i.imgur.com/cdYFPBg.png

Note that I'm using a customisation on the 'Rx AGC GAIN Adjustment' field. The default ASUS settings ( see

http://i.imgur.com/Gp9SD3B.png ) I feel are way too sensitive. A setting of 50 caused me some instability after around 12 hours. When the instability occurred I noticed that the SNR graph was starting to fluctuating on every tone in use. At first it was minor, then it slowly got worse and suddenly the SNR plummeted as if the AGC stopped working.

I'd therefore recommend, if anyone wants to try this device again before I've done a conclusion on most likely Tuesday, to try the following settings and see how it works for them:
Stability Adjustment: 6 dB to 9 dB
Rx AGC GAIN Control: 38 to 46
Tx Power Control: -3 dB to -5 dB
Bitswap: Enabled
ESNP: Stable

My line isn't too close to the cabinet sadly so I don't know how this will impact shorter lines, mine is approximately 500 meters I believe.

Optional:
If you have access to TC, I've found applying a delay of 2ms (and INP still set to 0) downstream has dramatically reduced the trickling of CRC errors I've often had, no matter what modem really, on ECI DSLAM's. No noticeable negative effects from this other than +1ms to the ping.

With 2ms on 40M/10M, at the time of writing this post I've been connected for nearly 3 hours with the following stats:

Code: [Select]

near-end path0 fec:     3881
near-end path0 crc:     11
near-end fec sec:       49
near-end err sec:       7
near-end ses sec:       0
near-end los sec:       0
near-end ua  sec:       0
far-end path0 fec:      9
far-end path0 crc:      1
far-end fec sec:        5
far-end err sec:        1
far-end ses sec:        0
far-end los sec:        0
far-end ua  sec:        0
P.S. If anyone interested wants the customisation I did (using Tampermonkey, a Chrome extension) for the DSL settings page then I'll post a link here. If anyone's interested let me know. Otherwise you can use F12 and edit the dropdown manually to input a custom value.

EDIT: Ugh, looks like the regrade with Zen is delayed as someone has to physically send the regrade order to Openreach via the Openreach Portal, not automated. It's been stuck on that since yesterday afternoon. My guess is that sales or whoever is responsible for doing that doesn't work at weekends. Looks like my conclusion might be delayed until Wednesday or Thursday sadly.

[johnny-bouy]

Thanks for all your hard work trying to sort out this router, I look forward to trying your final settings when finished.

[Ixel]

Thanks for all your hard work trying to sort out this router, I look forward to trying your final settings when finished.

You're welcome, thanks. Yes, late tonight I plan to switch to the DrayTek for a short time, maybe just until the morning to get a small sample of the potential error stats versus ASUS's error stats with my settings. I'm really hoping that the downstream sync rate is almost if not the same as what I'll get on the DrayTek. I plan to try an AGC VREF/Rx AGC Adjustment setting of 45 (currently 44) to see if I can just squeeze a little more out of it without instability.

Either way all being well I'll have the results of my current settings versus the DrayTek tomorrow. The settings I've been using have been stable for me. Currently syncing at 46518/11163, SNRM 6.9/6.2 (need to nudge downstream down from 7 dB to 6 dB as well), INP 0/0, delay 2ms/1ms, uptime 14 hours 33 minutes with 117 error seconds, 0 severe error seconds and 261 CRC errors. No SEF errors and no LOS errors unlike when I've used any of the AGC options on the UI. I also have plenty of crosstalk on D2 in the evening so the modem's bit swapping has been busy and appears to have functioned fine.

[Ixel]

Well, sort of bad news (at least for me).

First, the DrayTek synced at 62/12. However... it was unstable! The moment it got a connection (fastpath 80/20) downstream was getting error seconds and CRC errors (54 error seconds in approx 1 minute uptime for example). This I imagine can only mean one of two possibilities, 1) my line has a fault that I wasn't aware of when I had interleaving or had synced at a lower speed, 2) something internal is faulty. I've already changed from the SSFP filter (MK3) to a microfilter without any affect to the problem. The RJ11 cable has also been changed. There's no noticeable issue on the SNRM graph but maybe there's something on the QLN or Hlog graphs (which I'll need the HG612 for).

This might be why I've had a stability problem when I tried a AGC VREF of 50, possibly due to the modem becoming sensitive enough to pick up the problem the DrayTek Vigor 2860ac encountered last night. Either way it's frustrating. This does mean I need to push the AGC VREF higher in order to attempt to match the DrayTek sync rate on the downstream.

EDIT: I've now turned off the Devolo plugs to eliminate them from the list of possibilities entirely.