Vplus is a replacement for profile 30a, going up to either 30MHz or 35MHz.
The point with Vplus is that it is a new profile that is designed to work alongside the old 17a profile, at least when vectoring is in use.
The design of the old profile 30a is that, while it could be used alongside 17a, it couldn't be used
with vectoring alongside 17a. The problem was caused because 30a didn't use tones of the same 4.3175kHz width.
Vplus, Annex Q, seems to now be known as profile 35b. It solves the problem by keeping tones 4.3175kHz wide.
http://wholesale.tdc.dk/Produkter/Vplus_TDC_151027-v...
So the question ... Do will need new hardware modem or our current vdsl2 ones (any brand) can work depending how isp will deploy the (possible) service? example 17a with Vplus (mix)
It will need all sorts of new things...
- NICC will need to update the ANFP to allow frequencies above 17MHz to be used
- BT/Openreach will have to choose to buy DSLAM hardware that supports 35b
- Openreach will have to make new speeds available
- ISPs will have to sell new speed packages
- Subscribers will need new 35b modems to get the new speeds
- Subscribers who don't want to upgrade can stay on the existing 17a modems.
Unfortunately, it needs one more thing:
- A G.fast deployment will not be able to use the spectrum from 20MHz to 35MHz
As BT have gone into G.Fast heavily, I don't see them ever deploying Vplus/35b; it will cause them to lose a lot of the speed potential.
If BT decided G.Fast was not viable, they might indeed go back to considering a vectoring upgrade. If that required hardware upgrades, then I'd very much expect them to contemplate including 35b support too.