So for gamers with healthy lines, it doesn't matter whether you're on 'Speed' or 'Standard', first hop latency will always be the same on a per ISP basis.
Yes... BUT if your line does get errors then DLM is more likely to intervene if you are on Standard rather than speed. A couple of years ago I was thinking of moving to another ISP, but one of the reasons I didn't is because that ISP uses Standard profile. My line has weird error bursts every morning for a couple of seconds. There's a good chance that I would be permanently interleaved if on Standard profile.
I'm guessing MTBR only counts for ISPs that actually use BT RAS? BT, Plusnet and whoever.
No Openreach NGA uses MBTR too. The logical assumption would be it gets the info from the Element Manager.
What I don't quite understand is how it might differentiate between DS and US? Are we assuming DLM action is directed specifically at each one? Or is action based on some sort of aggregate?
Upstream and Downstream are counted independently. Its possible for DLM to just take action on the downstream OR upstream OR both.
My memory is hazy but I don't remember seeing any of these 'DLM' style features on the DSL DSLAM I used to work on.
I'm not certain, so don't quote me on this, but I don't think the older BTw MSANS collected any where near as much information about the line as what Openreaches' do.
Openreach NGA has specific aggregation element managers in the exchange which collects and controls data from several DSLAMs at various locations.
RAMBO itself is a separate server box and the DLM system it uses was patented by BT for BT wholesale Historically it was located near to the bRAS because it also controlled RAP. It communicated directly to the bRAS and collected data from numerous MSANs in numerous exchanges.
Openreach these days use MSE bRASes which means that most head-end exchanges have their own bRAS.