Hi and welcome
I must admit the introduction of the term IP rate by BT does seem to cause some confusion, and it was something I first queried myself during the beta testing phase of the new BTw Performance tester.
BT that seem to be introducing the difference names and terms without actually clarifying exactly what they are. :/
I'll try work through each one to the best of my knowledge... If anyone finds out anything to the contrary then they are welcome to add their 2p.
Connection Speed (Sync Speed)This is the rate at which your router connects (synchronises) to the exchange at. This speed depends on various factors and local line conditions. Obviously the better your line/nearer to the exchange you are the higher this will be. This figure can change each time you connect.
Maximum Stable Rate.This is set during the first 10 days on MAX and is used to set your Fault Threshold Rate. This figure has no real relevance on the day to day running of your connection, and is perhaps something we can forget about and ignore, because once its set, there is little you can do about getting it changed anyhow. More info on
MSR.
bRAS ProfileThe bRAS profile is a limitation of your speed at the RAS in an attempt to stop too much data travelling down the ATM backhaul and swamping the DSLAMs at the exchange, which apparently could cause packet loss.
Your bRAS profile is determined from your lowest sync speed over the 3 day period.
This is something only done by BT and doesn't occur on LLU.
Data RateThe Data Rate should mirror your bRAS profile, which is rounded down to the nearest 500kbps.
BT send your ISP a delta report, which advises them of any changes in your bRAS profile. BT state that the ISP should limit throughput in line with the bRAS profile and also any limitations on the account type - ie ensure that home Max accounts don't get more upstream than they should.
Note: The ISP can also use this to limit any ISP related account types for example if an account is provided by Max, but they want to limit the account to 1Mb or 2Mb speeds.
IP rateThis seems to be the one that causes the most confusion right now.
This figure is supposed to be what BT estimate your maximum throughput (real) speed should be after overheads - if all conditions were perfect. This figure is only a guide as to what speeds you could expect to see.
Finally..
Plusnets "stable rate" page.When BT first announced MAX, they advised ISPs that they would be introducing some limitations of throughput speeds and talked about Maximum Stable Rate. They told the ISPs that there would be speed limitations that the ISPs would be required to implement.
Since PN were one of the max trialists, PN set up something so that their users could see this figure.
Unfortunately for them, at the time this was called a stable rate and they called the page stable rate.. but this actually became what is known as the data rate and should not be confused with the Maximum Stable Rate. They removed reference to stable rate, but the fact remains that the word stable is still in the url which IMHO is what causes the confusion :/
The figure on that page should be your Data Rate.