Your attenuation would almost certainly stay the same, as it is based on the line characteristics between the modem you have and the one in the cabinet. Independent of the product. That negotiation doesn't have a clue what
ISP product, or even ISP, you are using. It's only when you log in that is determined, by which time the connection to the cabinet has been long-established. It does of course know which Openreach product has been ordered by the ISP.
I believe your noise margin will be around 6dB, set by Openreach according to the product ordered for the line. It's a complex subject and I don't recall seeing any stats. (Thinks - maybe I have some of my own, I was once on 40/2 .... No time to look now).
Although the line would still be able to sync at 50Mbps or so, (it's unclear whether you 50/10 is sync or throughput), it will be capped at 40Mbps by Openreach.
Because your sync is lower, than now your error rate will fall. On both downstream and upstream.
The big difference between the 40/20,
which is sync'ing as if it were 70/20, is that it was Plusnet limited the throughput, probably via the
Current line speed, to 40Mbps.
The indispensable man or woman passes from the scene, and what happens next is more or less the same thing as was happening before.
My broadband basic info/help site -
www.robertos.me.uk. Domains, site and mail hosting -
Tsohost.
Connection -
Plusnet UnLim Fibre (FTTC). Sync 58162/14182kbps @ 600m. -
BQM
Edited by RobertoS (Fri 26-Jun-15 15:30:34)