Minimum Guaranteed Download Speed

I changed from TT ADSL to TT FTTC in November 2017, and was given a Minimum Guaranteed Download Speed (MGDS) of 24 mbps at that time.

I have had a fair amount of problems with stability and dropping connections and some speed issues over the years I have been with TT. The FTTC change seemed to introduce a few of these again,and over a few months and many OR engineer visits the line was reasonably stabilised. Although, I was informed by the OR engineer that my connection to the FTTC cabinet is via a mix of copper and aluminium cables with quite a few joints - this cabling runs un-ducted to the cabinet - and was likely to deteriorate slowly with time and effect speed etc.

I have just attempted to renew my contract with TT and they want to apply a MGDS of 16mbps. Having looked at both Sky and BT availability checkers they state a MGDS of 21mbps; but TTs gves 16mbps. Do these checkers not use the same OR data to calculate speeds?

I've spoken to TT but can get no sense from them about the difference. Although at this point in time my line is stable and speeds are OK (27.3 down, 6.8 up) I'd sooner be able to raise a fault complaint at a 22mbps threshold than have to wait until 16mbps is the speed.

The line data may be the same, but what ISP apply in term of peak speeds which is a recent change introduced means you may see different figures even if they interpret the Openreach data identically.

I am talking about the Minimum Guaranteed Download Speed not a peak speed. There's something not quite right about TT dropping from 24 to 16 mbps; especially when both Bt and Sky calculate it at 22.

Its probably down to TalkTalk being very conservative with their speed estimates. They do the same with ADSL2+ speed estimates, theirs are often lower than other ISPs and at the low end of the BT checker results (if on a 21CN exchange). That's all they are - estimates.

In reply to a post by baby_frogmella:

Its probably down to TalkTalk being very conservative with their speed estimates.

And yet, in November 2017, Sky BT and TT all gave extremely similar speed estimates and MGDSs. A MGDS is not an estimate, it is a statement of guaranteed speed which can be referred to. It's not an estimated range which is so well loved by ISPs.

The rules around minimum guaranteed speed changed recently, it does take into account peak time speeds now.