topic Re: Sync speed good - throughput bad in Full Fibre

Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 10:20:18 GMT

Hey

I've called and have a BT engineer booked for Thursday - but I'm not entirely sure it's needed.

Our line dropped a couple of times last night and throughput speeds have dropped from 36mb to 14mb. The line however is still syncing at 41mbps...

I was using an unlocked HG612 but I've now connected the line directly to my DSL-AC68U and that too is syncing at 41mbps but getting a throughput of 14mb... Is it possible that somewhere on Plusnet's side my line is being banded? Wrong IPprofile?

It would be great if someone could check as the engineer visit is going to cause some headaches with childcare arrangements that i'd rather avoid.

Plusnet ID is Dickij03

Many Thanks

Josh

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 10:23:56 GMT

Line stats for info

Re: Sync speed good - throughput bad

jab1 — Tue, 04 Jan 2022 10:56:16 GMT

@dickij Welcome to the forums. Your stats indicate you are getting 41Mbps down/6.9 up, which looking at the line attenuation appears to be a little low on the downstream.

However, sight of the 'Additional Diagnostics' report from BTW Performance Tester would be a help in determining where the problem lies.

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 11:12:04 GMT

Thanks for the reply. I've done the test, attached. Maybe the IP profile isn't the issue.

I'm not surprised we don't sync any higher to be honest. The estate was fitted with aluminium in the 60s - and although in the last ten years fresh copper has been laid down they seem to only swap you on problematic sections... So I can't guarantee there isn't any Aluminium on my connection to the cab.

It seems my IP profile is 38 - which aligns with my previous throughput speeds of 34-36mbps...

My line seems to suffer with this problem 2-4 times a year - and it's always 14mbps it drops to... Coincidence I'm not sure - but something is wrong... I've even ran the speedtest built into the router, eliminating my internal network as a problem, and that too reports 14mbps 😕

Re: Sync speed good - throughput bad

jab1 — Tue, 04 Jan 2022 11:11:58 GMT

Aaaarghh - Aluminium. 😐

Looking at that performance test report and your other screenshot says to me there is something wrong somewhere, but to be honest I think you may have to wait for one of the Help Team to pick this up and run some internal checks.

Sorry I can't think of any other suggestions at the moment.

Re: Sync speed good - throughput bad

Townman — Tue, 04 Jan 2022 11:33:16 GMT

Data speed reports indicate USABLE speed - given the fairly good sync rate here (and the low SNRM) I would suspect that the line is very stable but has a high transmission failure rate. What is the phone line like?

Broadband is not going to work well if the "phone" line is not working properly.

Please perform a quiet line test - dial 17070 select option 2 using a corded phone plugged into the test socket behind the face plate of the master socket. It should be silent. A noisy phone line (or no dial tone) will have a marked adverse impact on the performance of broadband.

If the line is noisy or there is no dial tone, then a PHONE LINE fault needs to be raised with your phone provider. If this is PlusNet, you can report a fault on line using the button below. From the Q&A list, choose the one which matches the problem, 'open' the 'section' and click the trouble-shooter link. NB: If you receive a failure message (rather than a log-in prompt) then log-in to the user portal in a different browser tab and attempt to use the trouble-shooter again.

Phone Faults

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 12:00:51 GMT

Unfortunantly I can't test the landline - we haven't had a landline phone for 10+ years 😕

I should add that the DSL-AC68U has the ability to override SNRM target - I've tried it at 6db and got a sync of 33mbps - throughput still capped at 14mbps so I disabled the override and back to 41mbps sync and 14mbps throughput

Re: Sync speed good - throughput bad

Townman — Tue, 04 Jan 2022 12:07:29 GMT

Can you borrow one? For £7 or so from Argos they are invaluable diagnostic tools, for they can very quickly point to a source of problems which are not so easy to diagnose remotely.

Re: Sync speed good - throughput bad

RealAleMadrid — Tue, 04 Jan 2022 13:01:34 GMT

@dickij The first thing I would do is remove the Asus DSL-AC68U from the line and put the HG612 back. The AC68U is probably the worst VDSL2 modem/router ever. The modem chip in It doesn't get on well with Openreach DLM and can lead to generally poor performance, disconnections and reduced speeds.

Have you paid Plusnet for a static IP address? If so you may be restricted by the Current Line Speed profile, you can check this on the Broadband tab in your member centre account. Plusnet can give you a static IP without your knowledge under some circumstances so it is worth checking. The profile is supposed to track the BT IP profile but can get stuck.

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 13:05:09 GMT

Agreed on the AC68U being naff as a modem - I've just got it hooked up for now to confirm the HG612 wasn't the issue and it's easier to check line stats.

I've checked the member section and it states

Current Status: You are now using a static IP address.

Which is unsurprising because I'm sure I requested one about ten years ago when it was of use to me. Would still prefer to have one though as it comes in handy!

Re: Sync speed good - throughput bad

RealAleMadrid — Tue, 04 Jan 2022 13:18:48 GMT

@dickij So you are on a Static IP, what does the Current Line Speed tell you?

Re: Sync speed good - throughput bad

Townman — Tue, 04 Jan 2022 13:19:54 GMT

Odd! Where do you see that?

I have a fixed IP address (had one for as long as I can remember when they were free) but nowhere in my portal account can I see "Current Status" nor for that matter anywhere to manage the option.

What does the broadband page report your current speed to be?

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 13:41:15 GMT

Product: Unlimited Fibre
Estimated Download Range: 20 - 32Mbps
Estimated Upload Range: 4 - 6Mbps
Minimum Guaranteed Speed: 18.2Mbps
Current Line Speed (Download): 14.4Mbps

14... maybe it is stuck?

@Townman Static IP is under broadband and then at the bottom under Help and Settings. You can't do much there though other than confirm you have one and what it is.

Re: Sync speed good - throughput bad

Townman — Tue, 04 Jan 2022 14:03:10 GMT

Certainly looks like a stuck profile (good call on the fixed IP angle) - this will need a kick from the Plusnet guys around here @Gandalf @LaurenB @TheMightyAJ

Oddly I do not see fixed IP status!

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 14:17:23 GMT

Thanks for your help guys - hopefully they can resolve this as it's painful working from home at the moment

Re: Sync speed good - throughput bad

Gandalf — Tue, 04 Jan 2022 17:11:00 GMT

Thanks for your post Josh.

I'm sorry to see you're having speed issues.

From what I can see the speed profile on our side had dropped when your sync speed did through one of the drops you had yesterday, but when things picked back up, we hadn't yet automatically increased our profile.

I've done that for you now. Could you turn your router off and on? You should see a higher download speed afterwards.

I can cancel the engineer visit if you'd like, but it may be worth leaving them booked to look into the underlying drops.

Let us know how it goes

@Townman wrote:
Oddly I do not see fixed IP status!

That'll be because you've had your static IP for even longer, so we would've added it differently.

We can either add a static IP as an "Add-On" charging £5 or manually adding the component onto the account.

As far as I'm aware back in the day when you signed up, the only way we'd add a static IP was the latter.

Re: Sync speed good - throughput bad

dickij — Tue, 04 Jan 2022 17:36:28 GMT

We're back up in the high 30s, thank you

Let's see how it goes, if it's still good in the morning I'll call to cancel the engineer.

For future reference, is there a special form of words I can say on the phone if/when this happens again that the advisor will know what I'm talking about and resolve? As it seems like the fix is easy.

Many Thanks
Josh

Re: Sync speed good - throughput bad

Gandalf — Tue, 04 Jan 2022 17:48:55 GMT

@dickij wrote:
We're back up in the high 30s, thank you
Let's see how it goes, if it's still good in the morning I'll call to cancel the engineer.

Awesome, that's good to see!

For future reference, is there a special form of words I can say on the phone if/when this happens again that the advisor will know what I'm talking about and resolve? As it seems like the fix is easy.

Yup. We'd manually change the "Current Line Speed" you see in your member centre through adjusting the "Connection Profile" that's on the "Connection" tab of our CRM/accounts system.

This can be set at anything up to the maximum speed for your package though there's no real benefit of increasing it beyond your sync speed, so it should be set at just under the sync speed to match the supplier IP profile.

If the connection profile's below the supplier IP profile and you have a static IP, it'll restrict throughput due to the way that connections with fixed IPs are routed across our network.

Re: Sync speed good - throughput bad

Townman — Tue, 04 Jan 2022 20:42:29 GMT

@dickyj

Part of the issue here is that fixed IP address users are (a) not the norm and (b) there are different (slightly obscure) factors which impact DATA Speed performance. Join those two considerations together and there’s a risk that a good number of agents will not be aware of the finesse of this space. Some of the customers around here are old lags and have seen the oddities before.