Below Standard Wiring & Unusual Hot Weather Causes Major Problems

[#1]

Interleaving and vectoring are independent features. Interleaving may be switched on or off irrespective to whether your cabinet is one of the few with vectoring in use.

PS. Feel free to link to something rather than copy and paste.

[#2]

The term filtering, is taken to mean filtering out specific tones available for use to prevent interference on certain tones. - ie a broadband filter (low pass) strips out high frequency tones and ensures that only the lower tones used by POTs can pass through.
Another example is an RF3 which is sometimes fitted by Openreach to filter out problematic tones which are susceptible to RFI, they used to use these for EU's who lived near radio transmitters, but these days they have fallen out of favour as they often reduce sync speed on ADSL lines and seldom used with VDSL.

Im not quite sure where you got that quotation from, but someone seems to have amended what was 'processing' to 'filtering'.  The original source from Alcatel-Lucent says:-

The technology uses noise cancellation, in a similar way to noise-cancelling headphones, to increase data speeds on existing copper infrastructure.

../snip/..

The interference is processed by subdividing the spectrum into narrow frequency bands, known as tones, and processing each tone independently.

Although the original link is now dead, numerous sites re-quote the Alcatel article using the correct term 'processing'. eg here and it can still be viewed on Wayback machine.

With DSL's G.vectoring, the tones are processed in real time to develop anti phase compensation signals. These anti-phase signals cancel out the noise to give a cleaner broadband signal.

I'm trying to think of a very simple analogy to explain G.vectoring and why the term filtering is incorrect, the best I can come up with off the top of my head is:-

Say you have a wall that is painted a nice shade of mid-grey (clean signal). But then someone splashes black paint over it (noise), by careful analysis of the shades and tone of black we take its exact opposite colour white (anti-phase) in order to balance (vector) back to grey.

Filtering is the equivalent of removing a brick from the wall so that you can't see the black paint (noise).

>> You may also find interesting:- Nonlinear filtering algorithms for vector processing machines

Thank you for the link, but closer inspection it appears to be specific to vector processors and not DSL related.  The term 'vector' is quite generalised and can be used to describe several different things. For eg Photoshop uses vector graphics and filters, but these aren't the same as the G.vector transmission method that can be used with VDSL.

[#3]

It's an ECI cab.. hence me saying nothing that Plusnet or Openreach can do.

Well.... unless Openreach decide to rip out all the M41's. I'm sure a quite a lot of people would like that.

[#4]

>> my speed seems locked at around 50Mbs, and I read on your site somewhere it might be it's just stuck.

Yes it is possible that you may have a 'stuck' capped rate  and it is one of the alternatives I mentioned because there seem to be quite a few around atm which just wont seem to clear.  We'd need to see proper line stats to be sure - its usually quite easy to spot. Doing something about it though is a lot harder. 😕

However, barring a line fault, cross-talk is the usual reason for a large sudden drop in speed - as I mentioned I've lost circa 33Mb headline so far.

Last year I did a very rough analysis using stats from those who monitor their lines on my forum and who were on the cab since new. It averaged out at about 20Mbps per line. Its also not over yet. I thought mine was stable at ~24Mbp loss... until this month I got yet another cross-talker and another 9Mb instantly disappeared.

Honestly no amount of filtering will make any difference, It would take Openreach to roll out vectoring nationwide.  The chances of that happening, look slim to nothing right now.

I don't disagree with your original post that with hind sight the M41's were a poor choice for Openreach to make because of their inability to do system level vectoring... (and the G.INP issues)...  its just the rest of it didn't seem to quite make sense.

[#5]

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Excalibre68 wrote:

On the other matter of Crosstalk.

Check the link: https://en.wikipedia.org/wiki/Crosstalk

As the above info will show there are many different kinds of crosstalk but it all boils down to the same thing "Interference" and although it cannot be completely eradicated good filtering will normally deal with it.

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My point was, that if Excalibre68 thought crosstalk wasn't a problem due to "filtering" as they called it, or vectoring as anyone else would have called it, they're going to be disappointed when they find out there isn't any vectoring on their cabinet.