from all documents I have read it looks a no brainer to me that the obvious speed gains (and stability) are from vectoring. Profile 30A will boost short lines (including mine as I see I am using the highest frequencies on 17a) but those same short lines will still probably see pretty good boosts from vectoring because of crosstalk and in addition vectoring also helps longer lines that wouldnt be helped by profile 30a. Also vectoring removes most of crosstalk variance so lines will be less like a lottery with performance.
If BT are planning to boost speeds further on copper the question is will they do it the absolute cheapest way profile 30a or even just a new 100mbit product on 17a with no vectoring. Or will they do whats most effective but with possibly more cost aka vectoring. I can see personally how bad crosstalk can be but I am also aware not all lines are affected as bad as mine, the average effect on short lines in vendor documents suggests around 40% speed loss due to crosstalk. To me that means if the cost of vectoring is under 40% of the cost of the original FTTC deployment, it makes it cost effective. I expect it will be way under 40% of the original cost as its just upgrading dslam equipment be it software or hardware upgrade.
ECI's shelf idea if I udnerstand it right is actually potentially cheaper than a per card solution if you consider a per card solution potentially needs every card upgrading whilst the shelf variant if I understand it right just needs a new master card to manage all the individual cards.
BT Infinity 2 Since Dec 2012
Edited by Chrysalis (Thu 18-Apr-13 08:29:02)