Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: j0hn on August 28, 2017, 04:00:38 PM

Title: G.INP finally enabled!
Post by: j0hn on August 28, 2017, 04:00:38 PM
Quote from: MyDSLWebStats
minted

This is an advisory mail to let you know that G.INP is now enabled for your line
Only took since February 3rd!
I believe capping the line to force it to return to fastpath may have had an impact.

I think I might also be on the Standard DLM profile, even though I'm with BT (I don't have any T.V services).
The line was interleaved a couple weeks ago after only 2 days on fastpath, despite ES only reaching 1555 in 24 hours.
This time I left my cap on after returning to fastpath, and after 2 days instead of interleaving the line again, G.INP was just applied.
Title: Re: G.INP finally enabled!
Post by: lee111s on August 28, 2017, 04:17:25 PM
Only took since February 3rd!
I believe capping the line to force it to return to fastpath may have had an impact.

I think I might also be on the Standard DLM profile, even though I'm with BT (I don't have any T.V services).
The line was interleaved a couple weeks ago after only 2 days on fastpath, despite ES only reaching 1555 in 24 hours.
This time I left my cap on after returning to fastpath, and after 2 days instead of interleaving the line again, G.INP was just applied.

I had similar in that interleaving was applied after 48 hours activation on the 18th August with ES around 1600 per day. Had interleaving for a week and G.INP enabled yesterday.

Quite why it took that long for yours, I don't know. Similarly I'm not sure why mine was enabled so quickly, when others have quoted 5-6 weeks on average.
Title: Re: G.INP finally enabled!
Post by: tiffy on August 28, 2017, 05:02:49 PM
Only took since February 3rd!
I believe capping the line to force it to return to fastpath may have had an impact.



Glad DLM has finally done the business and applied G.Inp to your line.
A long wait indeed although you did state earlier in another thread that you considered 12th. June to be the actual, fully commissioned date for your VDSL line due to other issues with BT, still a record time by historical experiences of other forum members.
Title: Re: G.INP finally enabled!
Post by: NewtronStar on August 28, 2017, 05:11:40 PM
I am well pleased to here this Breaking News Flash and no need to find away to get a DLM reset
How many weeks is that since OR completed the E-side connection I can't remember now
Title: Re: G.INP finally enabled!
Post by: j0hn on August 28, 2017, 05:21:45 PM
Yes the order was completed on 12th June.
DLM completely ignored the line between 3rd Feb - 12th June with the line regularly having over 5000 ES/day but remaining fastpath the whole time.

Order officially completed on 12th June, interleaving applied on the 14th June. G.INP finally applied on 28th August, exactly 11 weeks after the order was completed.
Title: Re: G.INP finally enabled!
Post by: Chrysalis on August 28, 2017, 05:43:11 PM
congrats :)
Title: Re: G.INP finally enabled!
Post by: NewtronStar on August 28, 2017, 05:46:21 PM
No need to look over your shoulder now for DS errored seconds and enjoy the 40+ Mbps sync club  again :yay:
Title: Re: G.INP finally enabled!
Post by: j0hn on August 30, 2017, 02:42:34 PM
2 days later now on a 5dB profile   :P
Title: Re: G.INP finally enabled!
Post by: lee111s on August 30, 2017, 02:53:35 PM
Identical to mine it seems.

Had 5 ES in almost 2 days of uptime. Hopefully be dropped to 4dB soon  ;D
Title: Re: G.INP finally enabled!
Post by: NewtronStar on August 31, 2017, 09:26:34 PM
2 days later now on a 5dB profile   :P

What happened to 5dB its gone back to 6dB and your upstream is now active with G.INP
Title: Re: G.INP finally enabled!
Post by: j0hn on August 31, 2017, 09:50:30 PM
I know, lasted 24 hours.
The upstream is great with G.INP, should really be on by default with compatible modems.
Title: Re: G.INP finally enabled!
Post by: NewtronStar on August 31, 2017, 10:20:02 PM
The upstream is great with G.INP, should really be on by default with compatible modems.

Totally agree and said this after G.INP MK2 was forced on us by OR, G.INP was designed to have both DS & US G.INP active at the same time no matter what the SINS say
Title: Re: G.INP finally enabled!
Post by: kitz on September 01, 2017, 11:13:22 AM
The first steps I can understand.

- Line is on open profile for 2 days
- DLM starts on day 2.  By default interleaving will be applied - or rather more correctly INP 3
- 3-5 days for Re-Tx to be applied.

Why yours took so long for g.inp to kick in Ive no idea, but Im glad for your sake that it finally has.  It's the 3rd step for new lines that appears to be showing some varience.

IMHO Openreach have steps 2 & 3 backwards.  If retransmission is available, then it should be applied by default rather than interleaving.

I wonder if it perhaps why it doesnt,  has something to do with how trying to apply re-tx on lines that arent fully able to cope with it affected both upstream and downstream speeds.

One of the things we noticed is that rather than the usual INP 3, the INP value would be somewhere in the 40-50 region. (which we would expect for G.INP).   It became unbundantly clear during G.INP mk1 that there were far more 'incompatible' modems in use than Openreach anticipated, so they did a botch job by only applying G.INP/INP on the upstream for lines that needed it for stability... and at the same time changing downstream to have INP applied first by default then G.INP at a later date.
Title: Re: G.INP finally enabled!
Post by: ejs on September 01, 2017, 04:14:22 PM
I think the whole mess is due to Openreach's own modems (at the time) needing a firmware update for them to work with retransmission. So they had to start with retransmission off so that the Openreach modems running old firmware could establish a working connection in order to get the updated firmware.
Title: Re: G.INP finally enabled!
Post by: j0hn on September 01, 2017, 05:48:11 PM
Is there anyway to tell from line stats if a line is on retransmission low or retransmission high? or what stats to look out for changing? My IP profile after the last few resyncs suggests I'm on retransmission high.
Title: Re: G.INP finally enabled!
Post by: ejs on September 01, 2017, 06:50:22 PM
I'm not sure if it's possible to determine that from the available stats. Maybe an INP value significantly higher than what it was before (on Re-Tx low), although the INP value does tend to vary slightly with each re-connection anyway. Possibly INPRein >= 1 on Bearer 0. Some of the earliest stats from when retransmission was first introduced had B0 INPRein = 1.00, but perhaps later it became more common for B0 INPRein = 0.00 on Retransmission Low. The table in BT SIN 498 detailing the parameters of the retransmission profiles says INPMIN_REIN_RTX is 1 for all the retransmission profiles, although NICC document ND1436 gives INPMIN_REIN_RTX=1 for the higher retransmission profile and INPMIN_REIN_RTX=0 for the lower retransmission profile.
Title: Re: G.INP finally enabled!
Post by: j0hn on September 11, 2017, 05:45:41 PM
Posted this on another thread but relevant to ejs last post here...
I'm not sure if it's possible to determine that from the available stats. Maybe an INP value significantly higher than what it was before (on Re-Tx low), although the INP value does tend to vary slightly with each re-connection anyway. Possibly INPRein >= 1 on Bearer 0. Some of the earliest stats from when retransmission was first introduced had B0 INPRein = 1.00, but perhaps later it became more common for B0 INPRein = 0.00 on Retransmission Low.
I'm of the opinion this might be right.
Going by my last 5 or 6 resyncs, anytime I have had Bearer 0: INPRein: 0 - I have had an IP profile matching that of retransmittion low.
When I have had Bearer 0: INPRein: 1 - I have had an IP profile matching that of retransmittion high.

DLM is trying my line on a 5dB profile again. It's 11 days after it reverted back to 6dB, so a similar pattern to how DLM changes between fastpath/interleaving.
DLM resynced the line at 17:14, by far the latest I've ever seen.
Title: Re: G.INP finally enabled!
Post by: Chrysalis on September 11, 2017, 06:58:48 PM
You happy with it flapping between different noise margins?

Seems this snrm system is prone to flapping.
Title: Re: G.INP finally enabled!
Post by: j0hn on September 19, 2017, 08:24:11 AM
You happy with it flapping between different noise margins?

Seems this snrm system is prone to flapping.
Seems there's usually 2 or 3 days between dropping/raising the target. It didn't retry 5dB target for 10-11 days, similar to retrying fastpath after interleaving has been applied.

DLM put me in 3dB this morning. It's taken me from 42Mb (6dB) to 49.5Mb (3dB). Pretty good implementation if you ask me.

edit: 51.1Mb
almost back to my day 1 sync, with no crosstalk
Title: Re: G.INP finally enabled!
Post by: lee111s on September 19, 2017, 09:20:26 AM
Retransmission high so an IP profile of ~91%?
Title: Re: G.INP finally enabled!
Post by: j0hn on September 19, 2017, 11:13:40 AM
92.4%
retransmission high yes
Title: Re: G.INP finally enabled!
Post by: Dray on September 19, 2017, 11:17:27 AM
Mine is 92.63%
Retransmission high
Title: Re: G.INP finally enabled!
Post by: lee111s on September 19, 2017, 12:01:53 PM
Mine is 91.94% on 3db

77884 sync with a 71.61mpbs IP profile.
Title: Re: G.INP finally enabled!
Post by: Chrysalis on September 19, 2017, 12:54:36 PM
Seems there's usually 2 or 3 days between dropping/raising the target. It didn't retry 5dB target for 10-11 days, similar to retrying fastpath after interleaving has been applied.

DLM put me in 3dB this morning. It's taken me from 42Mb (6dB) to 49.5Mb (3dB). Pretty good implementation if you ask me.

its still flapping if its a 2 week gap.
Title: Re: G.INP finally enabled!
Post by: j0hn on September 19, 2017, 04:50:59 PM
When it doesn't "flap", it's a stuck profile.
It's Dynamic Line Management, it's surely supposed to change. A resync takes less than a minute.
I see no difference between a line changing from fastpath to interleaving, or a line gong from 6dB to 5dB. It's designed to gradually remove INP/banding when a line is stable so sensible to gradually lower the target snrm dB when a line is stable.

If it works like the rest of the DLM (it looks like it does) then if 5dB was rejected again it shouldn't try it again for 20 days (using the assumed "doubler" method).

Whatever instability was picked up last time (5dB lasted 1 day and reverted to 6dB with upstream retx) isn't there this time round. The line has continued on to 3dB. If it didn't try again (or "flap" as you put it) then I'd be 7Mb worse off right now. Excellent implementation imo.
Title: Re: G.INP finally enabled!
Post by: burakkucat on September 19, 2017, 07:24:02 PM
The key word, perhaps, is hysteresis (https://en.wikipedia.org/wiki/Hysteresis)?  :-\
Title: Re: G.INP finally enabled!
Post by: kitz on September 20, 2017, 01:28:50 PM
btw slightly off topic but talking of DLM.   The 21CN DLM system is getting a major overhaul - or rather was - as it was scheduled for work to take place this w/e but has been cancelled.

For the sake of clarity, when BTw say DLM System (http://www.kitz.co.uk/adsl/DLM_system.htm) they mean the hardware side and any software running on the system.  In this particular case it looks like new RAMBO boxes.