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Aspiring Contributor
2,402 Views
Message 1 of 5

SRA and DLM, does BTR even use SRA?

This may be a little long winded so I apologise, I'll try to be brief.

 

I've had Infinity 2 for a few years now, I was the first in our rural village to get it and originally connected with a HH5 which proved to be more trouble than it was worth. I don't actually recall my original sync speeds (Life with a newborn took over and things like broadband speed became somewhat unimportant) but I seem to recall they were around 62/18. Anyway, I changed the router for a good old TP Link W9980 which,because of internal building configurations, I ran off a 10m RJ11 cable to the master socket in the hallway.

 

I knew this wasn't optimal and that I would probably suffer for it but the TP Link seemed happy enough and gave me no line drops and my sync speed was always about 57/18 which I settled for. 

 

Now, move forward a few years and some alterations meant that I had the opportunity to run a CAT5 under the floor and site the router next to the master socket. I decided to upgrade the router to something more capable and bought a new Asus DSL-AC88U.

 

At first I couldn't get it to work on Infinity (point to note for anyone buying one, the 'Infinity 2' quick setup profile doesn't work, you have to manually edit the profile to enable 802.1q and set VLAN ID to 101 otherwise it just won't connect)

 

The Asus connected at the same sync, pehaps a smidge lower than the TP Link and I thought well, that's that then. After a bit of poking around I noticed SRA turned on and remembered seeing it on the TP Link too so I thought I'd turn it off and see how it goes. It lasted 8 hours, then the errors started and the line dropped. On reconnection interleaving was on at 1731 down and INP had kicked in, all reducing sync to 53/16. Over the next 24 hours it dropped again and lowered to 51/16.

 

At this point I decided balls to that and turned SRA back on, I'd rather have my old 58/18 rock solid connection back than let DLM mutilate my obviously noisy connection (17070 QLT produces mild noise, almost background digital. I do need to get round to killing the power in the house and doing it to see if it's my end or BT side but whatever)

 

Anyhoo, the upshot is my line is now sat at 51/17 interleaved with SRA on with zero ES for the last 24 hours and no drops. Will DLM relent and allow it to go back to my original sync with time or has SRA on/off made a right mess of it? Does SRA even 'work' with BT Infinity? If it does, what i the interaction with DLM? 

 

For ref BT checker shows the following for my line (router was power cycled after waiting 30 minutes a few hours ago but it's been 24 hours since I changed back to SRA and have shown zero ES up/down throughout);

 

VDSL Range A (Clean)72.4552014.149Available--------
VDSL Range B (Impacted)58.93517.37.630Available--------

 

And my Asus line stats (formatting messed with by forum);

Downstream Upstream SNR Line Attenuation Path Mode Interleave Depth Data RateMAX RatePOWER CRC HEC ES INP

6.2 dB6.0 dB
17.2 dB0 dB
InterleavedInterleaved
1731216
51103 kbps16937 kbps
62236 kbps16997 kbps
6.8 dbm6.8 dbm
00
00
00
4.00 symbols2.50 symbols
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4 REPLIES 4
Distinguished Sage
Distinguished Sage
2,390 Views
Message 2 of 5

Re: SRA and DLM, does BTR even use SRA?

It would appear that BT do not use SRA. According to these links, which are not exactly recent, they may be trialling it which could infer it is not being used at present.

 

 https://www.ispreview.co.uk/index.php/2016/08/bt-reveal-tech-details-expanded-long-reach-vdsl-broadb...

 

https://www.ispreview.co.uk/index.php/2015/01/bt-extend-uk-vectoring-trials-fix-fttc-fibre-broadband...

 

As regards DLM. If your line is now stable with no errors DLM should slowly release it back to your previous speeds. This can as you know doubt know take a few weeks.

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Aspiring Contributor
2,365 Views
Message 3 of 5

Re: SRA and DLM, does BTR even use SRA?

Hmm, seems odd then how enabling and disabling SRA makes such a marked difference. Which is why I'm enquiring really, I'm not sure if enabling SRA is 'right' but it does seem to stabilise what would appear to be an otherwise troublesome line.

 

I'm curious (if a little impatient like most of us) to see if DLM does indeed relent or if SRA enabled will have some effect on it preventing it releasing interleaving and so on.

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Sage
2,299 Views
Message 4 of 5

Re: SRA and DLM, does BTR even use SRA?

You mentioned there was some noise on your line when doing the QLT. DLM will not relent until you have the line noise rectified.

 

A corded phone is always best for perfoming the QLT and be had for  about £5 from a well known catalogue store.

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Aspiring Contributor
2,280 Views
Message 5 of 5

Re: SRA and DLM, does BTR even use SRA?

Update for those interested;

 

The storm last night caused a couple of power outages at 2am onwards so the router ended up with a couple of resets which will no doubt be a black mark in DLM's eyes. However, sync has gone up but interleaving not yet released. I'm well aware the process can take a LOT longer.

 

Notably, SNR has gone way down from the usual 6dB to 3dB and upstream speed is faster than it's ever been. DLM is obviously merrily tweaking away so time will tell but SRA is obviously beneficial to a noisy line.

 

DownstreamUpstreamSNRLine AttenuationPath ModeInterleave DepthData RateMAX RatePOWERCRC HEC ESINP

4.1 dB3.0 dB
17.2 dB0 dB
InterleavedInterleaved
1546253
55146 kbps19993 kbps
63328 kbps17657 kbps
6.5 dbm6.5 dbm
49
70
16
4.00 symbols2.50 symbols
0 Ratings