Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[j0hn]

You would probably get high 60's with a 3dB target, possibly just over 70Mb if the line made good use of the D3 band.

As more customers get added to the new VDSL Sidepod (which i don't think will be Vectored) you could see your downstream sync crash.

[GigabitEthernet]

Interesting, I wonder why. Did your attempts at sync capping in the other thread noticeably reduce the FEC count?

Something I have noticed though is I get a slight drop (by 1.0 dB) in downstream SNRM and one single upstream CRC error occurs each time I pick up the phone, then the SNRM returns to normal and a second CRC occurs upon hanging up. This is not causing me any issues so I will not be doing anything about it, but I'm just wondering if this is normal on VDSL2? I'm using a known good (on my old ADSL2+ line anyway) VDSL Mk3 faceplate for filtering. Perhaps if I ever upgrade to the 80/20 product and end up running at 3 dB target SNRM it might cause a problem as I'd then be dropping from 3 dB to 2 dB instead of 13.4 dB to 12.4 dB?

Yeah if you look at that thread I went from something like 20,000+ FECs an hour to about 10,000. Sorry I slightly over-exaggerated with the millions, although it doesn't take many days to get into the millions.

It's probably just a noisy line to be honest, I can't really be bothered to go into the reasons why, it's always been slightly baffling why I sync quite high on the downstream side of things for my line length (750m) but a bit low on the upstream side.

Your line is a bit shorter than mine but you'll see you have a higher upstream sync but a lower potential downstream. Doesn't make sense to me!

I wonder if 10,000 FECs per hour is the magic number and I would simply need to cap my DS sync more to see a benefit, might try that if I get bored.

Regarding the SNRM drop, it shouldn't do that. Sounds like the start of an HR fault to me.

[GigabitEthernet]

Ignore me, I can't read. Your line is shorter and so you see a higher expected DS and US as would be expected.

Curious to see more stats over time from another vectored line though.

You don't see your SNRM rise immediately after a resync then? It was an odd thing I always saw with certain modems, sync around 6dB and it would slowly rise over a few minutes to 7dB or more, almost like it took time for vectoring to activate.

[siofjofj]

Regarding the SNRM drop, it shouldn't do that. Sounds like the start of an HR fault to me.

I was worried you might say that, before my service was activated I was able to do the quiet line test on 17070 and did hear crackling. I won't be doing anything about it for now since it's not actually causing me any issues and since trying to get a HR fault fixed which made my ADSL2+ service completely unusable took 3 years and 12 Openreach engineer visits. Perhaps this, together with

As more customers get added to the new VDSL Sidepod (which i don't think will be Vectored) you could see your downstream sync crash.

means it is a good idea for me to stick with the 40/10 product!

I was half expecting my new order to be put on the new sidepod as my house has been empty for a good while and codelook reports 557 premises passed for my PCP and I imagine a large number of people choose VDSL due to the low ADSL speeds and lack of Virgin media or 4G signal, so I'd have thought the main VDSL cab (perhaps upgraded to 512 lines) is rather full. Perhaps my line was left jumpered in after the previous resident moved out.

Curious to see more stats over time from another vectored line though.

No problem, happy to post some in a few weeks time.

You don't see your SNRM rise immediately after a resync then?

No I don't, but didn't you find that the v2 DSL firmware stopped this behaviour? I've been on this firmware since day 1 since it was the last thing I flashed to my VMG8924-B10A when I was playing with building firmwares.

[GigabitEthernet]

Well I'm using a BT Smart Hub now but don't have any issues on that either.

Actually on the upstream side it syncs very well.

[burakkucat]

Regarding the SNRM drop, it shouldn't do that. Sounds like the start of an HR fault to me.

Agreed. A joint is starting to show either HR or semi-conductive tendencies.

[siofjofj]

Actually on the upstream side it syncs very well.

Just noticed on your other thread the trough in your D0 band. I have that too. Is this a usual thing for VDSL2 (DPBO for the benefit of ADSL lines perhaps?), or perhaps something seen on vectored lines?

Agreed. A joint is starting to show either HR or semi-conductive tendencies.

How annoying, I thought I'd have left those issues behind at my old address! Hopefully it won't get worse to the point where it becomes service effecting.

[burakkucat]

Just noticed on your other thread the trough in your D0 band. I have that too. Is this a usual thing for VDSL2 (DPBO for the benefit of ADSL lines perhaps?), . . .

Correct, it is the DSPBO to allow for exchange based xDSL services.

It is actually in the DS1 band. Only the US bands are numbered started from zero.