[LINK] ADSL problems with AAPT/Pacnet, NSW

grove at zeta.org.au grove at zeta.org.au
Tue Feb 19 10:49:23 AEDT 2013


On Tue, 19 Feb 2013, Noel Butler wrote:

> On Tue, 2013-02-19 at 09:17 +1100, grove at zeta.org.au wrote:
>
>
>>
>>> Lodged a service fault with pacnet?
>>
>> I did this on Sunday morning and had one call back 8 hours later to get me
>> to do the cable shuffle, ie plug/unplug everything, move the heavy cabinet
>> etc, which I dutifully did to fulfil my obligations to the scripted helpdesk
>> gods.....  ...this is in spite of me using the diagnostics of my switch
>> to comprehend that there was line sync and ATM connectivity etc.....
>>
>
>
> That can still occur with 'foreign battery' or other little quirks that
> can occur on the line.
>
> Do you have crystal clear phone conversations?

Pretty much.  When we were "migrated" a few weeks ago, we lost DSL and phone
both.  The next day, DSL was working but no phone.   Then it just magically came 
back in the afternoon.

> Although I've not dealt with DSL stuff for a few years now, often there
> was, and likely still is, buck passing from ADSL supplier to voice
> provider, recently with all the weather in Qld, my parents had cronic
> problems, removed DSL, called hel$tra VOICE and had a line test run,
> problem detected, and resolved 8 days later (required field tech, and
> this happened at the start of ex TC Oswald, so given the teleco mess all
> telcos had to deal with in SEQ/Wide bay, I think 8 days was most
> acceptable).

All our line tests have passed so far, so I do not think it is that.


>>> ADSL not working can mean anything, are you still in line sync? if so
>>> what errors does your modem report?
>>
>> I have Line sync, but the problem lies at the ISP PPPoE/auth server which
>> was going up and down without ever offering a route...
>>
>
>
> that can be a symptom of line fault as well as LAC and LNS etc etc etc

Hmmm, Ok.....


>> Not very happy if this is my regular "service" now.
>> It would seem they (AAPT or someone) decided to "stabilise" my
>> connection by dropping the attainable line rate, so I am
>> now at about 4495kbps now.
>>
>
>
> Definitely a sign of a bad line if you get stable around there but
> previously had a  lot better

I had a bit better before but not much.....   This what it looks like now....:

> adsl info  --linediag
adsl: ADSL driver and PHY status
Status: ShowtimeRetrain Reason: 0
   Channel: FAST, Upstream rate = 766 Kbps, Downstream rate = 4795 Kbps
                 Down            Up
SNRM(dB):       6.7             10.5
LATN(dB):       47.0            27.2
SATN(dB):       47.0            0.0
TxPwr(dBm):     0.0             10.6
ATTNDR(Kbps):   6192            800


By the looks of this, my maximum line rate is 6192kbps.  It seems to have improved
overnight again.  I have been tweakign SNR to boost the 4795kbps, but haven't done
that this time yet - the settings I make on this NB6 modem do not "stick".....

I used to get 1024kbps for my upstream, but that has been wound back, too....

>> When I signed up for the service, I was promised "Up To" 20000kbps ;)
>>
>
> Not sure if it's still the case, but hel$tra used to only guarantee
> DSL1 speeds, even on DSL2 ports, so I think the others would have too.

When I "upgraded" my service, it was supposed to be ADSL2+ but who knows?!

>> It's that "up to" that needs to be dragged through the streets
>> and flogged mercilessly - "up to" is the biggest cop out, ever.....
>>
>
>
> I think its fair given the myriad of factors that determine what you can
> reliably attain.

Hopefully NBN will fix this.  I spoke to an engineer scoping out our 
place on my way home the other day and we are just inside the rollout 
limit.   They are putting FTTH to all the townhouses in our strata,
which will be excellent....

> Do you know your local exchanges location? An old trick used was divide
> downstream attenuation value by 13.84 to get the rough distance in km's
> from the exchange, I say rough because that value is affected by line
> quality, line gauge size, extra phone points in the home and so on.

I am on "Orchard Hills" exchange.  I used to be about 1km closer to it.
I will have to work out how far it is now. 
>
> What are your line quality (SNR and attenuation) readings from your
> modem?
> SNR values representing a good line with always be into double figures,
> upstream will be much higher than down, so down should be at least 11 to
> be solid, but 10 is reasonable, are you able to debug your modem to see
> if it logs retrains?
>
> Attenuation is the opposite of SNR margin and should be as low as
> possible, 20-40db is optimum, though my personal DSL runs fine at 46DB
> (I'm almost at the end of the exchange run here).

Here are some numbers - I can telnet SSH into my home server again now (MacMini!)
and telnet to my switch to get the numbers - here we go!

(still learning what some of the numbers mean....)


> adsl info --show 
adsl: ADSL driver and PHY status
Status: ShowtimeRetrain Reason: 0
   Channel: FAST, Upstream rate = 766 Kbps, Downstream rate = 4795 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):       6.8             11.0
Attn(dB):       47.0            27.2
Pwr(dBm):       -25.6           10.6
Max(Kbps):      6180            800
Rate (Kbps):    4795            766
                         G.dmt framing
K:              150(0)          24
R:              0               0
S:              1               1
D:              1               1
                         ADSL2 framing
MSGc:           59              68
B:              149             23
M:              1               1
T:              1               1
R:              0               0
S:              0.9942          0.9600
L:              1207            200
D:              1               1
                         Counters
SF:             7921558         7528249
SFErr:          27568           123
RS:             0               0
RSCorr:         0               0
RSUnCorr:       0               0

HEC:            21789           143
OCD:            2211            0
LCD:            6               0
Total Cells:    1447033697              232919985
Data Cells:     15781945                1081717
Drop Cells:     0
Bit Errors:     0               0

ES:             4022            80
SES:            460             12
UAS:            14              4294349879
AS:             127980

INP:            0.00            0.00
PER:            16.15           17.76
delay:          0.24            0.24
OR:             32.18           33.33

Bitswap:        402             2518



Thanks for looking!


-- 
Rachel Polanskis                 Kingswood, Greater Western Sydney, Australia
grove at zeta.org.au                http://www.zeta.org.au/~grove/grove.html
 	The more an answer costs, the more respect it carries.



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