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[NewtronStar]

I am sorry but with only 24 hours worth of data on MDWS any opinion into whats up on your line  would be a shot in the dark 

[MaximusPrime]

@NewtronStar,

no worries, cheers for taking a look.

I've attached 10 days SNR Margin stats if any1's interested in having a guess why I get so much noise at night

[NewtronStar]

That looks like the SNRm decreasing on a longer line during the evening time due to RFI and the relents during the daytime and so on, have a look at your SNRm and then my own for the same 10 day period.

[MaximusPrime]

@NewtronStar,

sorry I posted my max attainable rate. I attached my SNR margin now.

Yeah I think you are right, but why have the past 2 nights been worse, my SNR during the day is 9db which is eating my speed

[NewtronStar]

I would see the SNRm lowering just like your odd SNRm in the last two days when nearby T/Storms are in the area and I know there has been that sort of activity on the 23rd and 24th with mad rainfall

[MaximusPrime]

@NewtronStar,

we've had some pretty heavy rain the past couple of days, no Thunder or lightning though, but maybe there was more electricity in the atmosphere, good point, cheers

[MaximusPrime]

Guys,

does any1 know why the Tones are missing in my Tone Graph?

It is 1 downstream band of Tones not 2, they should be there imo

[NewtronStar]

Unfortunately that looks like the normal power cut-back zone to stop VDSL interfering with ADSL it looks worse on your circuit as you don't have much bits per tones and it falls off showing no tones or bits available in that area.

[burakkucat]

I agree with N*Star's analysis and will add a subsidiary comment that from the extent of the power cut-back, it appears that your cabinet is quite some distance from its associated (telephony serving) exchange.

[MaximusPrime]

Cheers guys, I wasn't aware of that scenario,

Basically I'm screwed cause of the distance 2.8km

Edit: should I not have some bits there at least?

[burakkucat]

There are two distances that really need to be considered for a cabinet based G.993.2 (VDSL2) service.

The first is the most obvious one . . . the distance between the end user and the cabinet. That, by consideration of the the attenuation per unit length of the metallic pathway, will define the absolute maximum synchronisation speed achievable.

The second distance, that of the cabinet from its serving telephony exchange, is directly proportional to the degree of power cut-back applied to the G.993.2 transceiver's output. The power cut-back is required so that the G.992.1/G.992.3/G.992.5 (ADSL/ADSL2/ADSL2+) signals, originating from exchange based equipment, are not "drowned out" by the presence of the G.993.2 signals injected into the cable bundle at the fibre cabinet location. Basically, an attempt is made to try to keep all the signals in the D-side cable bundles at equal power levels.

[MaximusPrime]

@burakkucat,

I didn't know that, my cabinet is about 3km from the exchange too, so that's bad for me too

Openreach should phase out ADSL then

[William Grimsley]

So, if I get this right, the further away the end user is away from the cabinet and the exchange, the worse this issue becomes?

[MaximusPrime]

@William Grimsley,

they restrict the VDSL to reduce Cross Talk with ADSL services

the longer the line the more they have to restrict - if I've read right

[burakkucat]

Let me try to put together a purely fictitious example . . .

Consider a very small telephone exchange (back in the early 1970s it would have been an UAX13, today it is a System X remote concentrator) located in village A. It provides a telephone service to residents of village A and also that of the next adjacent village, B. Villages A & B are 3 kilometres apart. There are no PCPs associated with that exchange; all residents (of both villages) are connected by "exchange only" lines. For this example, we will concentrate on two properties in each village. The two in village A, EU-A1 and EU-A2, are the immediate, next door, neighbours to the exchange building. The two in village B, EU-B1 and EU-B2, are next door neighbours, by the duck-pond.

In the beginning, the only means of Internet access was by a dial-up service. EU-A1, -A2, -B1 and -B2 all had equally performing dial-up services.

Then a G.992.1 based broadband service became available from the exchange. Due to the relative distances from the exchange building, EU-A1 and EU-A2 obtained the full 8 Mbps DS for their broadband services whilst EU-B1 and EU-B2, being 3 km distant from the exchange, only obtained 3.5 Mbps DS for their broadband services.

Eventually money was found so that AIO cabinets could be installed in both villages, one outside the exchange building in village A and the other near to the duck-pond in village B. (Both of those AIO cabinets are fed from a fibre head-end exchange in the nearest major town, a long way away.) The new G.993.2 (VDSL2) service is announced as available to residents in both villages. In village A, EU-A1 is quite happy with his (exchange based) G.992.1 service and so does not upgrade. His next door neighbour, EU-A2, does upgrade and chooses the 80/20 Mbps DS/US service.Over in village B, EU-B1 looks at the estimated speed for the new service and she decide to upgrade to the G.993.2 (VDSL2) service. Her neighbour, EU-B2 decides that the current G.992.1 service is perfectly good enough for all that he requires (sending e-mail messages, etc).

All four residents occasionally meet together. Their conversation eventually turns to their respective broadband services. EU-A1 and EU-B2 still have the same throughput speed as when the first (exchange based) broadband service became available. EU-A2 boasts that his throughput speed has increased by nearly a factor of ten. (Originally 8 Mbps DS synchronisation speed; now a 80 Mbps DS synchronisation speed.) EU-B1 sulks because, although she is the same distance from the AIO cabinet in village B as EU-A2 is from the AIO cabinet in village A, she does not get the same throughput speed as EU-A2. ("'Snot fair! I pay the same as you.", etc, etc.)

The reason for the difference between the DS throughput speeds obtained by EU-A2 and EU-B1 is down the the power cut-back of the respective G.993.2 transceivers in each cabinet. The transceiver of the AIO cabinet in village A has a minimal (or no) power cut-back. The transceiver of the AIO cabinet in village B has a significant power cut-back.