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[sevenlayermuddle]

. . . as I think I'm maybe confused.

7LM is confused? With such a forum identity, I am very surprised! 

Now I'm going to throw a comment up into the air and see how it lands. Unlike the ADSL[2+] service with which we are all familiar, the VDSL2 service between the FTTC DSLAM and the active CPE (the HG612 modem) uses PPPoE, not PPPoA. Hence ATM cells are not part of the picture . . .

(I hope I've got that right.)

Ah so I was right.... I am confused
At risk of emphaising that confusion further.... I though HEC errors referred to ATM headers, and Mr Eagle is getting HEC errors reported?

With that I shall hush.    I have downloaded a copy of g.993.2 from www.itu.org and will attempt to get my head around it, but that could take some time with my limited attention span these days.  In fact, it could keep me quiet for quite some weeks.

[kitz]

Actually 7LM..  I highlighted your post and italliced the PhyR, because I thought that you may have been on to something.

When I looked at the error count..  the thing that immediately stood out to me about the CRC's was that they vastly outnumber the FECs, which is something that Ive never seen before.


----
*Added to clarify the obvious.....  on an interleaved line

[burakkucat]

Hi Mr. B*Eagle1,

(A certain scaredy cat dosen't like the look of that beak . . .    )

I'm not seeing any fault with your internal wiring from the OR installed gel-crimps, inwards, so when I agreed with what other visiting engineers had said, it was just that -- an echo.

However, after going to sleep with it present in my mind, I do now have one question to ask about your two pair, screened cable from the gel-crimps to the current NTE5/A. Is the metallic screening actually connected to a good earth? If not, you might have well just used CW1308 spec. cable . . .    To provide any benefit, you should earth the screening but only at one end. You don't want to set up any earth loops -- not a good idea.

[Bald_Eagle1]

Hi b*cat,

However, after going to sleep with it present in my mind, I do now have one question to ask about your two pair, screened cable from the gel-crimps to the current NTE5/A. Is the metallic screening actually connected to a good earth? If not, you might have well just used CW1308 spec. cable . . .    To provide any benefit, you should earth the screening but only at one end. You don't want to set up any earth loops -- not a good idea.

No, the screening isn't earthed.

I think it could be this cable http://www.maplin.co.uk/ultra-high-speed-adsl-cables-45164?ordercode=A97CG or something very similar.

I just happened to be in Maplins, looking for something else, & noticed it on offer (nowhere near the price in the link - it might have been 1/2 price or less).

I got thinking about my cabling at the time (cheapo white stuff, probably 20 years old or more, in a number of short lengths jointed by twisting the wires together & wrapping selotape around the joint before stuffing it under the carpet.
So I bought it, thinking it might be better.
It appeared to make no difference to my (at that time) 1Mb connection whatsoever.

The modem log reported a re-sync at around 5:45 this morning, so I unplugged everything apart from the broadband & rebooted the modem.

This resulted in a slightly higher speed (Line rate (kbit/s) 26497 DS &  4670 US, SNRM 6.1dB).

The connection has been up for more or less 14 hours now.

SNRM has now dropped to 3.8dB

Error count is currently:-

                  DS          US   
CRC errors    119034    0   
FEC errors    1216       24 
HEC errors    35356     0

I'll plug everything back in tomorrow morning & see if the error count shoots up again.

Speedtest.net doesn't appear to be working tonight, so:-



Paul.
 

[burakkucat]

No, the screening isn't earthed.

Well, it should be! 

When the original RJ11 plugs were attached to each end, I wonder what was done with the screening? I am beginning to suspect that it was nothing more than a marketing ploy to induce the gullible to part with more money -- "Never mind the quality, it is screened cable. (Just don't tell them that the screening is only for show.)"

I'm sure one of the other Wizards will be able to advise you on the sort of connector required to connect a earthing lead to the screening.

As for analysis of your modem's data, I'll leave that to Kitz, 7LM, Oranged, Jeff or . . .

Yawn. Excuse me, a cat-nap is coming on.

[Bald_Eagle1]

I'll plug everything back in tomorrow morning & see if the error count shoots up again.

Speedtest.net doesn't appear to be working tonight, so:-

Just for the record at 06:20 this morning, DS SNRM was 4.1dB

The modem has not re-synced overnight.
Throughput appears to be the same as yesterday:-




                                Downstream    Upstream 
Line rate (kbit/s)          26497            4670 
CRC errors                   121443          0   
FEC errors                   1270             48 
HEC errors                   35921           0   


Everything plugged back in at 06:40 (modem NOT rebooted).

I will monitor for errors etc. for 24 hours (assuming no re-sync events).


Paul.

[Bald_Eagle1]

No, the screening isn't earthed.

Well, it should be! 

When the original RJ11 plugs were attached to each end, I wonder what was done with the screening? I am beginning to suspect that it was nothing more than a marketing ploy to induce the gullible to part with more money -- "Never mind the quality, it is screened cable. (Just don't tell them that the screening is only for show.)"

I'm sure one of the other Wizards will be able to advise you on the sort of connector required to connect a earthing lead to the screening.

Hi b*cat,

I see there was a discussion on this some time ago:-

http://forum.kitz.co.uk/index.php/topic,5028.0.html

If nothing else, I got rid of the cheap cable with selotaped joints, & the braided shielding will no doubt provide some protection against physical damage.


Paul.

[Bald_Eagle1]

I will monitor for errors etc. for 24 hours (assuming no re-sync events).

Hmmm,

Kiboshed in just 1 hour.

I noticed this in the modem's log:-

2011-11-4 7:32:36 Notice 104500 DSL activate succeed
2011-11-4 7:32:20 Notice 104500 DSL deactivate

As this re-sync event "on the fly" only took 16 seconds, it will not be recorded in Plusnet's logs.
I note the dynamically obtained IP address is unchanged.

I wonder if DLM finally gave up on the SNRM level of 4.1 dB, & decided I would be much better off with a lower speed & higher SNRM.
SNRM is now back up to 6.3 dB, but I have lost quite a bit on sync/download speeds.


Line Rate (sync speed) is now down from 26497 K to 23780 K

& download speeds down from 24.83 Mb:-

Ping has improved from 25 ms though.

The recent change of profile from 8c to 17a MAY have started the 10 day training period all over again (Plusnet don't know whether it has or not), so I won't keep rebooting the modem, just to eek a couple of Mb more out of my connection.
Apparently sync speeds CAN go up & down during the training period, although I do note that they never went down during the training period following the initial installation.

This re-sync MAY have been caused by "something" in my other internal wiring as I maintained a higher sync rate & associated higher download speeds for 24 hours or so with it all unplugged.

It looks like I will now have to monitor this over quite a prolonged period, plugging my other kit back in one piece at a time until I find a culprit (if there is one).

Now if only someone could develop RouterStats (or something similar) to automatically monitor my VDSL2 connection at regular intervals............



Paul.

[burakkucat]

Mr Eagle,

I see there was a discussion on this some time ago:-

http://forum.kitz.co.uk/index.php/topic,5028.0.html

Hmm, useful comments from both Eric and Walter. (And tips, from the latter, on how to electrocute a cow! Oops, mustn't laugh.     )
 

If nothing else, I got rid of the cheap cable with selotaped joints, & the braided shielding will no doubt provide some protection against physical damage.

Indeedy. But b*cat would still prefer to know that the braiding is connected to a good earth.

Now if only someone could develop RouterStats (or something similar) to automatically monitor my VDSL2 connection at regular intervals............

That needs further thought because when one goes to the relevant page via the GUI, there is no corresponding URL displayed from which one could "curl" the data.

[sevenlayermuddle]

No, the screening isn't earthed.

Well, it should be! 

Without wanting to fall out with anyboidy else I agree, it should be.  Although I'm aware that not every body is as convinced as B'Cat and I are.   

The thing is, an ungrounded faraday cage can be effective providing the entire system is completely enclosed within the cage, but that's not the case for DSL.  My theory at least.   

That said, some of the 'super-cables' , regardless of their superfluous shielding, may offer other benefits such as increased twist-per inch, which would be quite relevant at higher speeds.

[Bald_Eagle1]

Hi b*cat,

That needs further thought because when one goes to the relevant page via the GUI, there is no corresponding URL displayed from which one could "curl" the data.

Just a thought, if one carefully hovers over the xDSL button inbetween screen refreshes, does that not reveal the elusive URL in the browser's status bar?
(http://192.168.1.1/html/status/xdslStatus.gz.html)


Paul.

[burakkucat]

if one carefully hovers over the xDSL button inbetween screen refreshes, does that not reveal the elusive URL in the browser's status bar?

S'pose that comes from having Eagle eyes!  I've noted down that information on my (ever lengthening) "ToDo" list.

[roseway]

Quite often, when a browser web interface doesn't display a unique URL for the stats page, this is because the stats are displayed via javascript on the main page. To get the details into Routerstats, see here. Click on 'Configuration section'.

[burakkucat]

Mr Eagle,

I have some not good news for you. After attempting to "curl" the relevant information from the HG612's page, I discovered that the device does indeed use javascript to display the information . . . just as Eric has mentioned. So a very simple "bash" script will not be able to obtain the SNRM at regular intervals, suitable for plotting versus time. 

[Bald_Eagle1]

Thanks b*cat,

I have discovered that this page does appear to provide SNRM, sync & other information:-

http://192.168.1.1/html/status/xdslStatus.asp

var DSLCfg = new Array(new stDsl("InternetGatewayDevice.WANDevice.1.WANDSLInterfaceConfig","Up","VDSL2","","4999","24153","0","0","5297","26756","66","44","0","0","63","109","G.992.3_Annex_K_PTM"),null);
var DSLStats = new Array(new stStats("InternetGatewayDevice.WANDevice.1.WANDSLInterfaceConfig.Stats.Showtime","232585","0","797750","0","7537","32","0","0","0","0","0","0"),null);
var DslUpTime = "53903";
var time = 1;

I thought I had cracked it to be able to use Routerstats.

But, in Routerstats it appears to wrap the details differently when it refreshes, thus giving spurious results for SNRM.
(Possibly something to do with the newline character - or lack of?)

Maybe it could be controlled a bit better in a bash script?


Paul.


EDIT:

It was interesting to note that I appear to be able to obtain the stats WITHOUT the need to log in to the modem itself, or the need to enable Telnet etc.
I wonder if a similar method could be used for automating the obtaining all the other stats that are used for the bit loading graphs etc.