It looks like I’ll be getting a visit from Open Reach but in the meantime I’d be interested if anyone would like to speculate on my issue.

When I leave for work in the morning at 5am I’ve got a steady 30-32mb download speed and 7-8 up
By the time I get home around 2pm download will be around 5-7mb and up is still 7-8
Now at 18:30 I’m lucky to get 2mb down while up upload is still 7-8

I’d assumed the line was being throttled at busier times but I’ve been on the phone twice to Plusnet and their equipment is telling them that my download is 32-33mb while I’m on the phone to them and only getting 3 or 4mb. I should say that these measurements are hard wired to the router with nothing else connected. They’ve sent me a new router to eliminate that being an issue but it’s not made any difference.

I’m pretty sure the problem is in the line somewhere, when the connection was made a few months ago after not having a phone line for a good few years the technician was having to work back up the line to a couple of the local cabinets to fix problems.

Anyway I know they’ll be someone on here who’ll knows the answer and who doesn’t want a chance to be right on the internet 😊

Connected directly to the router or over WiFi. Ours seems variable at best, i do wonder how much of that is WiFi rather than broadband. Our Xbox is about 2m from the router, over WiFi often get warnings about speed, cable direct to the router has sorted it.

It’s hard wired to the router so not a WiFi issue.

Contention. No one else on your street/box isn’t online at 5am.

As jam-bo says, contention. The speed the Plusnet agent is telling you will be the sync speed, that is, the data capacity of the connection to your router. The route further back is shared with somewhere 20 and 50 other people (20:1 etc is what they call the contention ratio), and if they are all using data your share of that is less. It shouldn’t be cutting your speed as much as that, but it’s probably not your line that’s the issue.

Contention ratio… The number of end users fighting over the available bandwidth. 5am… Most people are in bed. During the day during Covid, and evenings, is peak time. The cheaper your broadband, the higher your contention ratio is likely to be. Your CP isn’t going to admit that, they’d rather blame the wholesale provider (I am biased, however).

The other possiblity is REIN which you can pick up on AM radio. Trams, Ham Radio hobbyists, Christmas lights and faulty appliances can cause REIN, however I think it normally just knocks your connection off completely when your neighbours faulty dishwasher gets turned on at 7pm every evening.

I also suspect (without evidence, just personal observations) that the contention ratio is worse for legacy ADSL connections, H+ and 3g, to encourage you onto fibre and 5g contracts.

Yup rein will cause a pattern of drop in sync or worse case a sproradic drops of sync, does sound as mentioned above, kept very busy with what you have described, line will test perfect, in sync at quoted speed and minimal errors.if Actual speed is below whats quoted ,A Dlm reset can help short term.

There’s a few things….

1: Line sync rate – this is what Openreach will test, the speed that your router can atain to the BT modem in the cab/exchange. BT Openreach are contractually responsible for this AND THIS only

2: From the cab/exchange. Plusnet will contract to BT Openreach for a certain level of service. For example they have X users on that exchange so will buy Y bandwidth from BT.

3: Said service will be tunnelled across the BT core network to an interconnect/handover into Plusnet you will see this called an LNS. BT will try and load share all of 2 above across 3. But things happen so a particular inter-connect may get overloaded, so a router reboot can sort this as BT may point it at a diff interconnect after the reboot. ALL bets are off if Plusnet have saturated interconnects of course.

4: If slow downs are happening to say only certain sites, then Pluanwt could have core congestion issues on their preferred route (transit/peering) for those sites.

In general ADSL/ADSL2/VDALS2(FFTP) lines suffer more errors due to RFI (Radio Frequency Interference) in the evenings when people switch on their crappy XYZ LED lights etc.. But usually the line would drop and re-sync (taking a few mins to do so)

But to get slow downs a 2pm does sound more of a congestion issue rather than a line issue.

BT Openreach techs that go to people’s homes, are usually really approachable, have great local knowledge. So they will most likely talk/share with you their test results from your master socket (cuppa always helps)

Other thing you should do is learn how to login to the router and look at the line sync speed/uptime/ errors etc.. If its all rock solid then it will most likely be a congestion issue, if its all over the place it MAY be a line issue OR internal wiring issue. BT tech will test to master socket so if line is dropping all the time, and they say its clean, then you have an internal wiring issue.

Thanks all. I had assumed it was contention rate given the timings I just wasn’t sure if what Plusnet were telling me on the speed they were measuring contradicted that.
There is no internal wiring in the house just the master socket and speeds are the same using the test socket with a filter as they are using the faceplate connection.
I’m waiting on a call back from their faults department and I’ll see what they say. Good to have the info above though about what it is they are measuring on my line

Is contention still a thing? I’d put money on RF interference.

Do you have an immediate neighbour who works from home and uses powerline networking?

Is contention still a thing?

Yep, all telecoms networks are contended from the core to the edge.

Pretty obvious if you think about it, if everyone in the UK tried to hammer 100 Mb/s (or whatever their max line rate was) at the same time, the BW demand would be insane. Telcos dimension their pipes based on blocking probabilities and don’t design them any bigger than they need to as it costs money.

No different to phone networks, if everyone in the UK tried to dial the USA at the same time, the exchanges would block 99% of calls (even using VoIP).

I use power line adapters in the house, I’ve got an AirPort Extreme as a repeater but with that powered down and only one device hard wired to the router the issue persists. House is detached so at least the width of a driveway between me and any neighbours. One is a plumber so out all day but the other does run a bike parts online business from home. Previously I was running a Huawei 4g router and had no issues. I only changed as I wanted a second Internet connection alongside being able to use my phone. I’ve been running online meetings for clinical trials and I have the slide deck so didn’t like being reliant on a single mast for connection. I use one pc hardwired and one connected via my phone. I should again say none of this is running when I’m testing my connection speed. It’s one laptop hard wired to the router and if I then switch WiFi on on my phone I get pretty much exactly the same results

Almost certainly contention. If you can justify it this is what FTTP mitigates, as you have a faster pipe to the exchange. Unless, of course, it’s the exchange which is overloaded. Covid and everyone home working/schooling isn’t helping either.

Might be worth asking a friendly neighbour if they have the same speed problem.

Yep, all telecoms networks are contended from the core to the edge.

He’s not trying to get 100mbps though – the throughput is falling to 25% of the sync speed, which isn’t great to begin with.

I doubt his ISP would arrange for Openreach to visit if it was contention since they’ll get the bill if no fault is found.

Might be worth asking a friendly neighbour if they have the same speed problem.

Mum and dad are over the road and also on Plusnet, off the same telegraph pole in fact. They haven’t had any issues but to be honest they wouldn’t notice unless it was really slow for what they use it for. Obviously in normal circumstances the first thing I’d of done is go over there and run some tests.

On the possible interference would an issue be able to have such a great effect on download speeds while upload speed remains consistent and stable all the time?

I doubt his ISP would arrange for Openreach to visit if it was contention since they’ll get the bill if no fault is found.

IIRC it depends on the local exchange, some allow the operators to install their own equipment in which case any contention is due to the operators router / backhaul, smaller exchanges provide trunked services via Open Reach, so they would be responsible for contention etc.

NB That’s if it is a contention issue and not some weird line fault.

FWIW, this is why I like having a nerdy and militant ISP (Andrews and Arnolds). They track ping speed and latency constantly so if there was congestion during the day on a specific exchange they’d shout at the backbone provider.

If your parents live across the road I’d definitely ask them to run speedtest.com periodically to see if their speed fluctuations match yours.

An update: Open Reach engineer has just been, said does it to this then this then this. I said yes that’s it exactly what is happening. It seems that the fault lies in the BT Wholesale infrastructure and is effecting  quite a few of the local exchanges but doesn’t effect every customer. He said they are very aware of the problem but haven’t yet identified exactly what bit of kit is at fault but he’s been to dozens of people with exactly the same issue. The line of course is fine and there is nothing wrong with the router and he said contention was really an issue with the fibre connections, the only time the network being very busy might be a problem is when trying to access the same servers as everyone else and that was typically evident with gaming consoles.

When I first opened STW around 15 mins ago I was getting 28mb download, now it’s at 7. It will probably continue to fall for the rest of the afternoon and will be over 30mb by the morning. Hopefully the exact source of the problem will be found soon

I’ve had this and it turned out virgin had oversubscribed the lines, where it should of been 30:1 or 50:1 I can’t remember exactly they were running at something like 150:1.

Plusnet have got back to me again saying it’s taking longer than they hoped to resolve my problem. Not surprising really as it’s in the BT Wholesale network. They are telling me that as they have not been able to fulfil their minimum speed guarantees that I can if I wish exit my contract with them.

The question is though if as the Open Reach engineer said the fault is in the BT Wholesale network am I going to see any difference in moving to another provider?

I had an issue with slow vodafone broadband in the evening & I fixed it by using Cloudflare DNS servers (1.1.1.1 and 1.0.0.1) rather than the usual ones the ISP provided. Might be worth a bash, might not.

It looks like they have now identified the problem, either that or moved me onto an exchange they know is working as speeds have been high 20’s low 30’s for the last few days.