Print

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

[kitz]

SNR (Signal to Noise Ratio) fluctuates throughout the day depending upon local conditions..  the higher your SNR Margin, then the stronger the signal is.  With MaxDSL, when you sync up, the DLM at the exchange will give you the highest speed it can depending upon what your Target SNR is set at.
Whilst Target SNR and SNR Margin are related - they are not the same thing.

Looking at your stats after a reboot, the DLM has your Target SNR set at 9dB.  Therefore upon syncing the DLM will give you the best speed it can whilst giving you an SNRMargin of 9dB as a "buffer zone".
Obviously after sync up - your SNR Margin will continue to fluctuate.

Theres more info about SNR, SNR Margin and the target SNR - An explanation of SNR and SNR Margin.

>> I have tried endless resyncs to try and rectify the Upstream & downstream Sync

As mentioned above your (downstream) target SNR is set at 9dB.  This is fairly normal so not too much you can do about that.   However the 256 kbps is odd and it looks like Tiscali for some reason may have limited this on one of their profiles.  Thats not a typical BTw upstream sync and looks like Tiscali for some strange reason have limited it.

Hmmm - stop!
 - Ive just checked Tiscali LLU profiles

>> Sync Down: 4960kbps

Just checking - Could that figure by any chance actually be 4096?
I think we may have just found (well at least 1 of 3 possibilities) which profile Tiscali have put you on.  WTH tiscali have limited your upstream Ive no idea and put you on that profile, since your upstream looks fine.

I could be wrong - but it looks like to me that tiscali are perhaps buggering about changing profiles seeing if that will correct your fault rather than actually passing on to BT.
Whats the stability of your line like atm?

>> I have asked them about whether it is switched on or not,.... /snip/... is there an alternative way

They should easily be able to tell you..  but most routers will tell you somewhere.  Which router are you using?

[jid]

Hi kitz,

Thanks once again for the reply!

I am using a D Link DSL G624T and cannot find anything on Interleave or if it is on or off.

I always did have a low Upstream speed before, as when I was getting speeds of 6.5mbps, the Upstream was only 241kbps via thinkbroadband.

The profile couldn't be limiting the speed, as I have synced at 5184 today?

Do you think that it is worth mentioning again that the Upstream has all of a sudden dropped from 448kbps, to 256kbps?

Would be worthwhile asking them to turn it on, if it is off, to see if my speeds will improve, or shall I wait for their result from the exchange config check?

Atm, the line looks like this, last resync, 11am this morning.

SNR Down: 10dB (was just 8dB, refresh of stats updated)
SNR UP     : 27dB
Atten        : 30dB
Sync Down: 5184 kbps
Sync Up     : 256kbps

Thanks Again

jid

[kitz]

Hi

The

Code: [Select]


4096 High SNR  4096  256      Adaptive:Fixed
4096 High-Interleave 4096 256   Adaptive:Fixed

profiles are fixed at 256 upstream yet allow the downstream to change but with a top limit of 4096.


On your old account the upstream may have been fixed at 288, which is what the upstream speed was prior to BTw bringing out adslmax. Tiscali LLU also has an upstream profile of up to 896 kbps which is fully adaptive. 

However your now sync of 5184 puts paid to the theory that you are on one of the above profiles.  TBH Im really not sure what Tiscali are playing at - but it would appear that they have limited a line to 256 which is capable of more.

>>> Do you think that it is worth mentioning again that the Upstream has all of a sudden dropped from 448kbps, to 256kbps

I would!  Theres no reason I can see why your line should be limited to 256 up - theres plenty of spare SNRM for more.  Make sure that you mention it appears to be constantly fixed at 256 no matter how many resyncs and despite the fact you have plenty of spare SNR Margin to cope .

[jid]

Hi kitz,

I have just come home to lunch to find that my broadband stats are looking much better!

They now look like this:-

Down SNR: 12dB           Up SNR: 24dB
Line Atten: 30dB           
Down sync:6112kbps       Up sync: 448kbps (woohoo!)

I still do feel that the line is capable than much more than this, I this sync will mean that I can only download at about 5meg?

They have told me that they refreshed the line profile which told them that the line was syncing at 6.3meg.

Regards

jid

[jid]

Hi kitz,

Thought I would let you know that I have now been told that there is nothing more that they can do 'apparently', as checks at the exchange identified no fault with the configuration. 

Could you have a look at my stats since they updated my Line Profile, as I am sure that the line is capable of more than this:-
Down SNR: 12dB           Up SNR: 22dB
Line Atten: 30dB           
Down sync:5888kbps       Up sync: 448kbps

I have now noticed the downstream snr is always at 12dB but may now and then drop to 9dB.
Also after a resync it connects on 13dB almost all of the time and then drops to 12dB.

I have asked them to do checks to show them that my line is capable of more and if they still cannot sort it out I think that I will have to write a letter to them with a log of all the speeds I have had since the upgrade.

I feel as if I am not getting the speeds I should be getting for the stats of my line as you have previously told me, and that I am not getting what I am paying for.

You advice is most appreciated.

Regards

jid

[roseway]

With an attenuation of only 30 dB your line should be capable of more. Clearly the target noise margin is set at 12 dB, which will reduce the connection speed somewhat, but this will have been done to stabilise an unstable connection. I don't have time at the moment to look back over the entire thread, but if you've done all you can to optimise your own internal wiring setup then it's probably best to leave things alone for a few days to see how it goes. I rather think that you won't get far by nagging BT at this stage.

[jid]

Thanks for that.

The thing is, the broadband is now loosing sync a lot in the evenings, and I mean a lot.

Only since they have 'refreshed' the profile.

I will be mentioning this to them tomorrow.

Thanks again

jid

[kitz]

Thats alil  bit more like it!
But like you say - it should really be capable of a bit more.

>> I have now noticed the downstream snr is always at 12dB

If after every resync its always around 12dB , they've obviously put you on a 12dB profile. However it is usual for the SNR to vary thereafter  until the next resync

I think unfortunately Tiscali are still trying delay tactics playing with your profiles, rather then getting an adsl engineer out to look for a fault on the line :/

>> there is nothing more that they can do 'apparently',

As mentioned ages ago - they seem to be doing all the tweaking at the exchange..  and havent actually got BT involved yet?

[jid]

Thanks for the reply kitz,

I will talk to them a bit more about it next week but if they still can't do anything I will be writing a letter to them.

Regards

jid

[kitz]

Good luck jid
Hope they do pull their finger out.

[jid]

Yep I do too!

Thanks again kitz and to everyone else for your advice. It is most appreciated.

I will keep you updated

Regards

jid

[roseway]

Good luck jid

[Ezzer]

The thing to remeber about getting your profile reset by the isp is that the profile changed via the exchange for a reason, and unless the problem which caused it in the first place has been resolved, then resetting the profile can easly cause the drop of sync's which you seem to be suffering from.

You don't ride a bike at full belt if your still on wet cobbles, your liable to fall off. the dlm is acting like a break to keep the connection safe, sounds as if you really need an engineer to check things out, so with the analogy, put your bike on a nice smooth dry road 

[ailema]

me here when it rains and windy i got no connection very very rude grrrrrrrrr

[jid]

Hi kitz,

I have had an update from Tiscali today and they have told me that they are running even MORE tests on the line!

Are there anymore to run!? They must have covered them all by now at lease twice!

Regards

jid