What does this mean......

Hi All

For the Netgear DG834Gv4 I get this off of Routerstats via Telnet

Status: ShowtimeRetrain Reason: 8000
Channel: FAST, Upstream rate = 443 Kbps, Downstream rate = 3147 Kbps
Link Power State: L0
Mode: ADSL2
Channel: Fast
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 6.2 18.5
Attn(dB): 54.5 28.7
Pwr(dBm): 0.0 13.1
Max(Kbps): 4216 860
Rate (Kbps): 3147 443


Now my question at this stage is the Max(Kbps) figures, especially the DL one. What is the relevence of this in regard to actual sync "rate". ???

What about the Link Power State as being L0

Lastly, does this mean the line has been put back into the 10 Days training period "Status: ShowtimeRetrain Reason: 8000" because I certainly was not aware of it or the reason if that is the case???

Thanks for any insight on these

In reply to a post by Routefinder:

Now my question at this stage is the Max(Kbps) figures, especially the DL one. What is the relevence of this in regard to actual sync "rate". ???

It's a theoretical maximum based on a calculation with your attenuation.

What about the Link Power State as being L0

means it's operating on full power

Lastly, does this mean the line has been put back into the 10 Days training period "Status: ShowtimeRetrain Reason: 8000" because I certainly was not aware of it or the reason if that is the case???

no, it's just a code saying why it was resynced

Many thanks for the rapid repsonse

I swapped out my Thomson TG585v7 for my older Netgear DG834Gv4 because it would not allow wireless access control to be locked when using my BlackBerry Playbook. With the Netgear I can MAC filter and 'lock it down' ~ much prefered IMO.

However, I will post under a new post after I have examined my records as my sync speed has dropped badly after my ADSL2+ training period, appears to have gone in progressive steps with many days of stablity at the 'then' speed............................the Netgear when last used beat the Thomson for sync on the 20CN network so not sure if the switch out is the prime reason for my mostly recent speed drop.

As I say not relevent to this posting and will start a proper thread when I have collated my info to share for the feedback

A quick suggestion.
It may well be that the training period started off with a default 3dB noise margin but either it wasn't stable or there were too many errors causing it to be increased to 6dB.

In reply to a post by Oldjim:

A quick suggestion.
It may well be that the training period started off with a default 3dB noise margin but either it wasn't stable or there were too many errors causing it to be increased to 6dB.

Good thought but no, my Margin has been solid in the 6db 'bracket' since before the 21CN switch. About the most reliable part of my connection :lol:

Your noise margin on 20CN is largely irrelevant because your line has physically been moved to connect to different equipment in the exchange and a new training period started. The most it could indicate is that your line wasn't subject to large variations.

In reply to a post by jelv:

Your noise margin on 20CN is largely irrelevant because your line has physically been moved to connect to different equipment in the exchange and a new training period started. The most it could indicate is that your line wasn't subject to large variations.

Point taken but the copper & aluminium between the house and the exchange has not "changed", so as you say (for all the oddities my long line has or could throw up) it has shown itself to be Margin robust for a very long time

ADSL2+ uses twice the frequency range of ADSL.

The higher fequencies are more susceptible to noise, for some reason. (Maybe there is more around up there). As a result, the error rates could be much higher if there is a source of considerable noise in those frequencies somewhere between the router and the exchange. Note, I specifically say the router, as the source could be local.

High error rates could cause a re-sync.

ADSL2+ is definitely more sensitive.

Which isn't to say this is the root of the problem you have. Just that stable noise margin behaviour on ADSL is not necessarily relevant.

Difference is

1. Higher frequency, so attenuated more, plain physics
2. Different noise sources so stuff that may be ok for ADSL causes issues
3. RF behaviour i.e. bridged taps

Push any medium closer to its limits and errors are more likely

In my own case the differance between the additional atten from 2+ can be seen daily. now on a wbc connection via madasafish (plusnet)

At night on the 3db target snr router resyncs to adsl2 with a atten of 48.8 sync aound 4443
Reset after 8am I get 3db target snr router resyncs to ADSL2+ with atten of 52.1 sync around 5318 depending on local noise.

Previously to wbc on max I was on atten around 48 and sync around 4200 most of the time.with a 9db target snr see thread here http://forums.thinkbroadband.com/freenetname/f/40840...

Hope that helps

I am on 21CN ADSL1 - at my request and these are my stats
Noise Margin: 4.6 dB (default is 6dB)
Connection Rate: 5024 Kbps
Line Attenuation: 50.0 dB
The reason it drops from 6dB to 4.6dB is that the higher tones drop out in the evening and don't re-establish.
Looking at the graph of frequencies actually used there is virtually nothing above 800kHz and even immediately after a resync the bit loading over 840kHz is very low

And the 3dB difference is a doubling of actual attenuation, because twice the number of frequency bins are involved.

Once you plot the bins out for a line, particularly the marginal ones at the ADSL2/ADSL2+ cross over it is obvious

Is that how the actual calculation is done.
Although ADSL2+ goes up to 2,200kHz I would be surprised if the attenuation calculation rates all those bins equally.
I suspect it depends on the router calculation algorithm and whether the tones used are the theoretical maximum or the actual tones in use.
http://wiki.kitz.co.uk/index.php?title=Attenuation_i...

The averaging is probably weighted according to how many bits are allocated to each tone, so the calculation is fairly complex, and different modem/routers can use different algorithms for making the calculation.

Thanks for the ongoing feedback but sadly some of it is now going over my head

I took a screen grab of the Routerstats bit tone graphing and here is the link (sorry file size is bigger than intended but did not want to lose viewable details by reducing the colours too much.

http://1stdesignit.co.uk/random/bit_tone_page.bmp

So, any added insigt of what this tells you & me would be welcome.

As noted above here again is the copied info about the conection itself

Channel: FAST, Upstream rate = 443 Kbps, Downstream rate = 3147 Kbps
Link Power State: L0
Mode: ADSL2
Channel: Fast
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 6.3 18.8
Attn(dB): 54.5 28.7
Pwr(dBm): 0.0 13.1
Max(Kbps): 4020 828
Rate (Kbps): 3147 443

Many thanks again in advance

In reply to a post by adamtemp:

In my own case the differance between the additional atten from 2+ can be seen daily. now on a wbc connection via madasafish (plusnet)

At night on the 3db target snr router resyncs to adsl2 with a atten of 48.8 sync aound 4443
Reset after 8am I get 3db target snr router resyncs to ADSL2+ with atten of 52.1 sync around 5318 depending on local noise.

Previously to wbc on max I was on atten around 48 and sync around 4200 most of the time.with a 9db target snr see thread here http://forums.thinkbroadband.com/freenetname/f/40840...

Hope that helps

Hi

Very intertesting that your "Max Rate" is equal to "Your Current Rate" whereas mine is not thought granted my attenutaion is higher???

Which is what I would expect - maximum frequency in use is about 750kHz so ADSL2+ would have no advantage over ADSL2.
In fact, other than the slightly better algorithm, ADSL1 would give similar results
You do realise that you have also posted your IP address in the image

Hi Oldjim

Thanks for the insight..............I surmise that is why the training period defaulted it back to ADLS2 flavour not 2+

It does seem that I am getting quite close to ADSL Max figures though (I will post to discuss/share later) I was getting a small but welcome improvement in sync and measured speed until a few days ago!

PS thanks for the heads up ~ now cropped and re-uploaded Hopefully no harm done???