Unlimited Fibre what would cause a slow connection speed below the guaranteed line speed ?

[#1]

Hi,

I have just noticed that my connection speed has dropped over the years. When I first had it fitted with BT, I was getting nearly 80mps (probs about 150m from the BT cabinet - BT Wholesale BB checker stats attached )

but I just noticed that the router is only syncing at 44mps and 46mps now. Plusnet gurantee is 55mps for my line. I have raised a query with PLusnet. But was just wondering what are the causes for this type of drop of connection speeds, contention on the line ? when I first had Fibre fitted, there was only one cabinet out there, but now there is 2-3. would broadband contention ratio cause this kind of drop ?

I have swapped out the faceplate at my end for a new one, but its still the same connection speed. 

The house is a new build under 15 years so surely the BT cables should still be good ?

Thanks

D

[#2]

Welcome to the forum

You certainly have a fault that needs investigation so you need to start by eliminating any possibility that the problem is on your property. First do a phone quiet line test by ringing 17070 and selecting Option 2. If there is background noise on the line then report a PHONE fault.

Next take the front off the your BT Master Socket (you may need to remove two screws or it might click off). In behind you will find the Test Socket. Plug a filter in here, connect the filter to your router and test speed using an Ethernet cable between your router and a computer. If it's still slow then we know that the fault is most probably external to your property. At this point you should report a fault to Plusnet explaining all the tests that you have done. If you report the results back here it will probably be picked up by a Plusnet staffer in the next 24 hours.

As to external causes, contention is not the issue we had in the old ADSL days. The biggest issue these days is crosstalk. This gets worse as more and more users use fibre and all the high frequency data from the many subscribers are transferred along a multicore cable back to the fibre cabinet. The signals cross couple between lines increasing the background high frequency noise and by doing so limiting the speed of subscribers.

Another cause is what is known as a Hot SVLAN where the BT infrastructure can't cope with the amount of data traffic, I guess this is a bit like the result of contention.

I've no doubt that there's a myriad of other causes that might not be hardware fault related.

[#3]

Thanks for replying,

There is some noise on the quiet test, but im not sure if that is just my old wireless phone getting interference tbh.

I dont have any filters anymore  ( been using BB faceplates for years ) so I cant do the test socket, but like I said I did swap out the old faceplate for a new Mk4 faceplate with another intergrated filter the other day with zero difference in sync speed.

Plusnet are investigating the issue so hopefully they will pick up what the issue is or escalate it to Openreach.

[#4]

Hi there.

I'm sorry to hear you're experiencing speed problems.

Line tests aren't finding the cause of the problem but it could be caused by cross-talk at the cabinet which is interference from fibre connections as others go onto fibre. As your speeds are below estimates I've reported a fault to our suppliers.

Congestion at the exchange typically doesn't affect sync speeds, but only throughput.

As you've tried the master socket and a different filtered faceplate the next step would be to arrange an engineer to further investigate. If you can reply to this ticket with your availability for a visit letting us know over here when you've done so we'll be happy to book the appointment in for you.

[#5]

Thanks for all the support around this question guys.

I have repiied with two full days that I am available for an Eng.

Hopefully its an easy fix and the enginner isnt dismissive of the issue.

Thanks again.

D

[#6]

Thanks @Donaldo

I've booked the appointment in and updated you via your account.

Let us know how the visit goes.

[#7]

Hi all, 

Just to update you all, the BT eng came and sorted the line fault.....router is now syncing at 78mps down and 20mps up.. so thanks again to everyone for looking into this for me.

However my download speeds are the exact same as before 44mps but I will give it a few more days before moaning about that, just in case it fixs itself

cheers

Don

[#8]

Hi Gandolf, is there a download limit on my profile ? Surely with a sync of 78mps now I shouldn't be downloading bang on 44mps at various times of day ?
Thanks Don

[#9]

It could be that your profile has not yet been updated after the fault was cleared. Normally the profile is updated overnight, but if you are still getting the same issue tomorrow it may need PN to give it a nudge.

[#10]

just to let you know Gandolf, the eng said the issue wasnt at the cabinet but the connection in my street, he lifted the porthole rounf the corner...I am assuming there is some kind of hub and that was the connection to the cabinet and that was the issue...it took him nearly 2 hrs to sort it all, but he did a great job.

[#11]

Glad to hear the engineer has improved your speeds Don

From what I can see the speed profile on your account updated to 75000kbps at 3pm yesterday.

If you can drop your connection and reconnect you should see a higher speed

[#12]

Sorted 👍
Cheers Gandolf 😁

[#13]

Yay. Glad to hear that Don!