Evenin' All,Rather than respond individually, I'll just provide an update.
Plusnet's Alex has confirmed he has discussed this case with BT who advised him that the line had been Port Flexed and the DLM system reset.
He also confirmed the Port Flex is simply a reset of the broadband port I am connected to in the cabinet. The DLM reset is a reset of the DLM system which controls my line.
The BT agent asked Alex to monitor my line for the next 24 hours to allow the DLM reset process to complete and to get back in touch with them if my speed has still not improved. He will re-check this tomorrow and take any further action needed if required.
Well, my IP Profile (bRAS) is now 24244 k.
It was at that level when one of the engineers requested a profile reset some time ago.
However, shortly afterward it dropped back to around 15000 k.
I do hope the improvement from around 22Mb to 24.2 Mb is not classed as a suffient improvement to avert any further action.
A property less than 100m across the road from me has estimated FTTC speeds of 27.9 Mb downstream based upon speeds achieved by consumers in the area.
I believe
I was that consumer as my download speeds were stuck at that level for a while shortly after the start of the gradual decline.
Touch wood, my line now appears stable with no unforced disconnections or crackly phone lines.
We now have absolute confirmation that attenuation values for FTTC only take into account the D-side line between the end user & the cabinet (as suspected all along - despite what my latest visiting engineer stated).
The only thing I don't have is a record of my line's attenuation from when it was achieving higher download speeds, to use as a comparison with the recent verbally reported value of 23 dB.
From what have gathered about FTTC, it appears that higher speeds can be expected up to a distance from the cabinet of around 1200m. Thereon, speeds tail off dramatically, no doubt due to the different frequencies used for FTTC, resulting in higher attenuations than for the same line length being used for ADSL.
I have also gathered that FTTC download speeds are usually a lot closer to the bRAS than is the case with ADSL - maybe quite a bit over 90% compared to around ADSL's 85%.
What I don't know is whether or not my current attenuation of 23 dB is about right for my distance from the cabinet of around 820m.
If it is, I very strongly suspect it must also have been around 23 dB when I was achieving higher speeds.
If my attenuation is currently substantially higher than when FTTC was installed, there must still be a problem with the D-side that wasn't present for the first couple of weeks following installation.
Plusnet have previously confirmed that no records exist from the original installation & I only started keeping records following my speeds suddenly dropping from 33 Mb to 27-28 Mb. At that time I thought a 5 Mb drop was a problem!!
razpag recently quoted a line length of 488m when obtaining a JDSU attenuation reading of 13.5 dB & speed of 39.9Mb. The next time he installs FTTC on a line length of 820m. I just know he will be bursting to confirm the attenuation & SNR values in this thread
. It will address so many questions in one hit.
So, will my speeds improve significantly over the next 24 hours via DLM?
They have not done so previously, so I suspect not.
Is a bRAS (IP Profile) of 24 Mb now correct for my line?
Not if it has achieved much higher speeds in the earlier days.
What else needs to be physically done to get my connection back to the equivalent of a brand new installation with 40 Mb at the cabinet?
Possibly a simple lift & shift?
Has my speed been capped via DLM due to all the disconnections & crackly phone line over the last 2 months?
Probably, but what is now causing my profile to be "stuck" - faulty electronic equipment in the cabinet or at the exchange?
Why are we continually going over the same ground?
Can it really be a simple lack of knowledge of how FTTC actually operates?
The various engineers who have visited my home all appear to have a slightly differing take on matters, so maybe it is.
Plusnet also previously admit they are not too sure either.
What's with all the "Baldy" references already
?
I'm not saying where the other feathers were being plucked from other than to say I don't need all 3 from the back, crack, & sack wax treatment
More news tomorrow folks.
I already have it typed out - "Success - 35 Mb bRAS, 32-33 Mb downloads back again"
Paul.