In reply to a post by MrSaffron:

Easest version: there is a rule saying they cannot do vdsl from inside exchange

Why not?

I'm less than 500m away from the Exchange, sure I don't expect Fibre, but why can't I get VDSL?

Surely VDSL is simply another interface, which could be located just as easily at the Exchange as it is in a Cabinet - the only real difference is that it must be a lot cheaper & quicker to provide!!

^{([cough] For someone asking for help, and given what as I said to the poster was a very good reply, that was extremely rude response from you )}

Anyway, have you ever looked at line stats from your router? If you haven't, we will need to go a little further. But if you have, you may have seen something like this-

Down            Up
SNR (dB):        6.1             6.7
Attn(dB):        19.5            0.0
Pwr(dBm):        13.5            7.3

Maybe you don't know what a DSLAM is.

Your router contains a single-line modem. A DSLAM is a rack full of "line cards". Your phone line is connected to one, and a modem on the line card is assigned to your line.

That power figure is what the DSLAM in the FTTC cabinet is supplying on my line.

There's a lot of other stuff feeding out of the exchange, like a few thousand phone lines and ADSLx such as you are currently on. That amount of power and the radio frequency emissions from a VDSL DSLAM situated in the exchange could screw up all those.

Even with non-EO lines, the power output on a line such as mine is carefully regulated to make sure that as it passes through the normal phone cabinet on its way to me it doesn't mess up any ADSLx lines running through that cabinet.

Does that help?

OK, I'm less than 500m away from an Exchange.

What is the fundamental difference, in the copper cable, between my Cable & someone else with 500m to a Cabinet?

They both go through the same range of multipairs & connections. If I was to get that level of interference, as you imply, so would the guy 500m away from a Cabinet!

Because radio noise from vdsl can clash with adsl2+ is the actual reason

The crosstalk from the two signals interfering

Hi John.

This bit of my reply to the OP possibly answers your question.

"Even with non-EO lines, the power output on a line such as mine is carefully regulated to make sure that as it passes through the normal phone cabinet on its way to me it doesn't mess up any ADSLx lines running through that cabinet".

I guess that level of control of the VDSL2 power within the exchange, plus the huge number of adjacent cables that have to be protected en masse from the VDSL2 kit and emissions/signals, would render the result at your end not worth the candle.

At the end of the day, as MrSaffron said, the regulations imposed on Openreach say no. Because of these factors and risks.

To fit the rule yes.

Vdsl is already held back to avoid interfering in the street

I do know that space was an issue at some exchanges in the past with ADSL. However, given they can fit a VDSL DSLAM for who knows how many lines into a cabinet on the street and the line is already connected to an ADSL DSLAM at the exchange and more and more people connected to the exchange are being connected to VDSL DSLAMS in cabinets on the street rather than ADSL DSLAMS at the exchange I somehow didn't think space was an issue.

Hypothetically, if I'm fed from a Cabinet 500m away, I would have a choice between ADSL & FTTC (aka VSDL)? But that same arrangement of Cabling, if fed to an Exchange, would create interference problems?

MrSaffron, I know you well enough to be confident that you are giving valid answers, but I really DON'T get it!

It is complicated and only understand as did rf electronics back in 80's

Reasonable precautions but rule is under negotiation suppossedly now lots ofreal world data