Broadband?

[Grant]

Eh Grant, you missed the part where fibre optic signals can be amplified with a much lower impact on SNR too, whereas copper is susceptible to ingress/egress of electromagnetism and radio waves. Fibre can be amplified easily with the inclusion of inline nodes and tbh, attenuation isn't much of a problem in fibre, there are whacking great fibre cables running between continents along the ocean floors and they have no issues with hundreds if not thousands of miles between headends.

TBH the gauge of copper wiring used in a lot of local loops is tiny which is why ADSL will never support more than 20-30Mbps, it's just not worth it as the wiring at the end user is useless, a lot of BT wiring in houses isn't even copper three-pair. You could do as much upgrading of the network as you want and have RG59 or above from the house to the exchange, but as long as there's shitty telco wiring in the house it will bottleneck.

Also bear in mind it's a transmission of voltage using the line, if there's any break in insulation you will earth either partially to the atmosphere or fully to the ground. Even bare cable at any exposed point can cause packet loss.

Very valid points, none of which I am disagreeing with you on.

I assume you work for Sky? As I have never seen a node with a signal amplifier in or repeaters to that fact. All of these are contained at the exchange. Thus bringing us back round to distances from the exchange. But other companies may run this differently. If so BT should probably up their game The only signal interfering node we use are splitter nodes. And then that's only traffic management, nothing to do with speeds or dB losses.

Out of curiosity, are you also referring to the Japan-England FLAG optic cable?