Is Plusnet limiting speeds?

[#1]

In the past I have generally got between 30 and 40MB/s on my connection, guaranteed speed of 32MB/s. Recently this has dropped down to between 8 and 12MBs. I've just had an openreach engineer out who has fixed a few issues he found with the wiring in the cabinet, but I am still seeing the same speed. The engineer shows his testing all shows we should be getting 40/10 speeds.

The odd thing I am seeing is that when running a speed test is that there is a very short burst of speed well above 12Mb/s and then it seems to sit at nearly exactly 12Mb/s for the rest of the test. This doesn't look like variable speed due to load or a fault, it feels like there is an artificial limit in place.

I can understand if there is a need to apply a limit in the current crisis if network load is high, but it would be good to know this is the case, rather than thinking I should be getting better speeds.

[#2]

My speed dropped last night 29th April 2020.   Was   42/10    recently consistent   36/10    now      30/7.5 

Variation in speed tester is possibly how they test using different files sizes, some testers take longer (Which Magazine = lots of different files sizes?)  others like BT test (crappy new interface and advanced test NEVER works)  is much faster and maybe less accurate. 

[#3]

Yes per a post today I'm on Fibre Extra and always got about 70Mbs above the guaranteed 62Mbs - recently my line speed seems to be capped at 26Mbs.

It would be good to have some info from Plusnet on this, a yay/nay.

[#4]

I'm on Fibre unlimited Extra at 80/20.  My regular download speed is always around 42Mbps with upload of around 6Mbps.  There is no evidence on my connection to suggest that speeds are being capped.  Hope that helps.

[#5]

If ?  broadband connections work anything like Ethernet CSMA CD (Carrier Sense Multiple Access with Collision Detection) 

Essentially all systems on the same piece of wire (big generalisation) = multiple access, all see all the traffic = carrier sense, (another generalisation)  collision detection = when any card sees traffic it backs-off and waits a random amount of time before trying to communicate again, meaning all cards don't try again at the same time and stop the network.

Then, FASTER connections mean the network is less likely to be overloaded,   OK sounds obvious 🙂  

What happens if the network is slower is that it is swamped by "re-tries"  of cards having waited a random amount of time  trying again to communicate, finding the network is still busy, waiting and then trying yet again and again and again.

In theory your home network would do the same thing (if it had sufficient clients). 

Point !    

If they (the ISP) artificially slow the network it is more likely to stop completely as Ethernet does when it is overloaded at around 35%  ish  utilisation !   The faster it can run the more quickly connections complete and free up the wire.

Conclusion.

An ISP artificially slowing their network could well achieve the opposite effect of stopping everything instead of simply getting people off the wire as fast as possible and allowing the next connection. 

[#6]

If I was seeing varying speeds throughout the day as demands increase and decrease I would be inclined the believe it is a load thing, however I am consistently seeing the same speed whether it is 10 in the morning or 11 at night, my speed tests look like a flat line, which is why I am leaning towards it being limited somewhere.

[#7]

Yep !  

A.  Each customer has a "profile" where I believe speeds are set, this is controlled by the ISP and can (now) be reset by them or possibly by the Openreach guy when visiting a customer.

B.  On top of that the line is monitored electronically probably with kit at the exchange. This monitoring takes into account all sorts of things and works to maintain connectivity.  For example if there is noise on the line or if there are repeated disconnections (maybe caused by the users repeatedly power cycling the modem or disconnecting the cables to the modem) the speed may be decreased to maintain the connection.  This is a vast and complicated subject and if you can't sleep at night (and the BB is still connected ! ) you can spend many happy hours trying to understand it all.

Setting "A" isn't the end of the story, if "B" kicks in then the max speeds you can achieve will be set lower (as I understand it in the profile "A".

My experience is that having it set (42 maybe) didn't last long and it soon ended up at 36, above my contract threshold for no penalty swap to another ISP of  32. 

I lived quite happily at 36 Mbps, for general PC stuff and Prime video.  reduction to 30 is getting too low. 

The ISP has a system to log your line and this is often included in any ticket (will post name  when I find a copy)  has test results electrical  /electronic noise detected info etc.

For ADSL and FTTC  I very strongly suspect that most faults are either the line from where fibre ends at the cabinet and twisted copper pair starts to the master socket, (end of their responsibility) or at (within) the home.

Answer to copper cable faults isn't good, lots of checks by Openreach if you get past the we will charge you £xxx.yyy   if the fault is at your house.

[#8]

I have had the same problem .I was enjoying 43Mb/s for a couple of years up to November 2019 when I renewed my unlimited fibre broadband. It dropped to 19.6-20.1mb/s and was rock steady .Plusnet were unable to get any response for improvement from Openreach. I put up with this "half Speed " poor deal until two weeks ago when my new 4k tv streaming was poor, due to it buffering when other devices were downloading. Plusnet said it was fixed last week due to cross talk etc.(complete rubbish) it did not improve the speed because my test of the line shows the maximum download achievable speed of my line from exchange to my house is 20.73. Like yours it never deviates. I have raised my complaint with the Ombudsman and the today they contacted Plusnet, and surprise their investigations for fixing the (CAP) has been halted with an email statement, saying if they don't fix it (Openreach) I can leave without penalty payments. But I do not want to leave and if I am forced to leave I will demand 50% back payment of my nine months broadband payments to cover the over 50% reduction in download speed for this period.