Gigafast 900 terrible d/l speeds - can you validate please?

Hi All, It's been so long since I was here (back in ADSL days) so I had to create a new account for this post.

This is a long post so a quick summary is: I have had VF 900 Gigafast FTTP for a year, it's been fine for 11 months. 4 weeks ago my speeds got very bad to some sites, not all. I have worked with VF Support and now they are no longer supporting me. I am having to leave and being asked to pay a termination fee. I am contesting that.

What I wanted to do is ask for the help of some of you experienced folks to give me any suggestions or challenge me in my analysis and position. Essentially, I want to make sure my point of view is acceptable and VF view is not! I'm happy to be challenged but I am 100% certain I have an issue but VF are saying they are working as expected.

If you are able to take the time to read this and reply/help, thank you!

I have had VF Gigafast 900 (900up and down) for a year. It has been mostly stable and I have been very pleased. I really don’t want to leave but I am at my wits end.
For 11 months, I had up to 900 down to most places within reason. I of course didn’t always get 900 to / from all locations but in general, it was very good. I had what I guessed was congestion at peak times and was perfectly happy accepting that. I could 9 out of 10 times get 800+ from sites like sourceforge, apple support downloads, google drive etc. I also had very high 800+ from usenet servers using 20 concurrent connections. When I ran speedtest.net tests, I got 800+ down from many (but not all of course) servers, most of the time.

Just over 4 weeks ago, I started to notice that I had very slow downloads from various sites I had known to be able to cope with 700-900 previously. I also noticed that downloading from my usenet providers were both considerably slower. I put it down to congestion and left it. After a week, I saw no improvement. I noticed that I could replicate the issue 100% and raised a case with VF.
Here is my situation. This has only happened for the past 4 weeks. All speeds in Mbps

I can download files from my google drive account at 600-700+ without fail.
I can download files from Microsoft download center at 600-800+ without fail.
I can download files fromcnet (as an example) at 600-800 without fail.
I can consistently get 900+ down from Speedtest.net (Vodafone Watford) only.
https://speed.measurementlab.net/ shows 900 up and down
Upload is not an issue, I can get 800-900 UP to most speedtest.net sites. My offsite backups are as fast as they ever have been. Clearly the link is capable of 900 down.

However, from 4 weeks ago, this started to happen:
I now get terrible download speeds to sites I know to have worked well in the past. This is consistent for 4 weeks, it is never better.
Sourceforgedownloads are 10-15 max. without fail.I cant get mirrors to improve.
Ubuntu downloads are <8
Apple downloads (I use this frequently) are 10-15 max without fail.
Amazon downloads (as an example, their Desktop Music App) max out at 10-15 always.
I build raspberry PI stuff and now the downloads from their site are all 10-15 max.
Many other tests at other sites are showing the similar download speeds and are consistently poor, not fluctuating.

All these tests have been tried but a few colleagues at the same rough times and they get close to their max download speeds. For example, a friend on BT FTTC 80 gets 70+ on all of the above.
Nearly all other Speedtest.net sites (not Watford) show 10-50 download. Some as high as 300 but rarely. Known servers that would give 800+ will now give 10-15
Thinkbroadband speedtest shows 140 burst x6 but 15 TBB down https://www.thinkbroadband.com/speedtest/16214228826...
Fast.com shows 190 with 8 connections
Any of these files are consistently downloaded at 10 – 15 Download Test Files | thinkbroadband
I don’t know how to prove this so it is conjecture but for the first time in years, I seem to get Youtube downgrading the video stream at times, I assume due to poor speeds.
It may have been a coincidence but on 12/13 April, my ping went from 5 to 12-15. This I know because I have a local monitor service. I am not sure if it is related but for 11 months I had 5.

I have (and VF actually agree finally) proven my devices and routers/ONT. I have Win10 Desktop, Win 10 Laptop and iMac i7 all showing exactly same results. I have used the VF router and my 3rd party Asus 86U and both show same. PC in ONT same. Many different browsers across OS’s. Different ports, cables have all been tested.
These issues are seen on my normal setup with switches and cabling etc. so all VF testing has been direct cat 6 or 7 cable in LAN port, no wifi. Using Desktop and Laptop. The good / bad results are the same regardless. I never test over wifi of course.
I am certain I have proven my devices, routers and ONT are fully capable of achieving the 900 down speeds at certain endpoints.

What I can also demonstrate is that I have consistent, repeatable poor download speeds to many known good sites and services. I can also consistently show poor speeds to many speedtest sites. I use these as a comparison, I know these are not all equal.
VF Support and now Customer Complaints have said if they can show the service has good speeds to the one server location at speedtest.net (Vodafone Watford) they are not able to help me any more with the speed issues I am having and they are not at fault. I have not been able to speak to one person in these 4 weeks and many many calls that is prepared to even discuss or help with the obvious issues I have on this service. All I have had is repeated requests for speedtest.net screenshots and “are you using a PC” type questions.

I want to fix this issue but VF will no longer support me. I am really disappointed that I have not been able to find someone helpful enough to discuss this and that whey are saying no further help. I am left with my only option to leave. They tell me I will need to pay a termination fee and I am refusing.
I am now in deadlock while VF look at the case and if they don’t change their mind, I will have to raise with cisas. Something I don’t want to have to do.
Sorry, this is so long!

Do you have any advice? I recognise that I can demonstrate 900 down in some cases. But I can also reliably show very poor speeds to known good hosts. I am not sure how to best show this. My issue is with poor real world download speeds to certain routes and VF will not discuss.
I am happy to try anything you can think of. Even if you wouldn’t mind just comparing the download speed you get to some of the examples I show above. They used to be fast for me!

Thank you for reading this ramble, take care.
Edit: If you can think of any other large download sites or testing I can do, please share!.

Edited by deleted (Wed 19-May-21 13:11:25)

This is a classic indicator of a congested link somewhere between you and thinkbroadband!

Hi, thanks for the reply. It would seem that way woudlnt it. Perhaps the cause of all of the other site speeds being so terrible too.

Do you think in your opinion that VF should accept this as a fault? Or help to understand the cause or fix?

Thanks.

This may be a complete red herring, but i've recently had very similar behaviour with a multi-site network I support (96 sites, sever thousand users). Our symptoms were that some sites were always at full speed and repeatably certain sites ran at a fraction of full speed, including this one coincidently.
Ultimately it turned out to be an MTU issue. The WAN provider for each site had made a change and the max MTU had dropped.
Once we'd found the right figure it works as it should.

As I said possibly a red herring, but worth a shot.

Thank you for taking the time to reply. That is interesting. Do you think that is a setting VF side? It will be a little difficult to address as they dont want to accept there is an issue.

Can you test the speeds where they are reliably bad but this time use a VPN, eg Nord etc.
But bear in mind Nord might max out at about 300-400Mbps, but if you are only getting 15Mbps or so on some of these places then the increase should be obvious.

If VPN "fixes" it, then go back to Vodafone and tell them this.

In reply to a post by laneyweb:

It may have been a coincidence but on 12/13 April, my ping went from 5 to 12-15. This I know because I have a local monitor service. I am not sure if it is related but for 11 months I had 5.

It's very probably related to the issue that you are seeing, which as said has all the hallmarks of congestion or a device issue somewhere deeper in their backhaul network.

There is little point repeatedly "discussing" this with first line support, you need to insist that they escalate the issue to a higher level of support, that understand the true nature of the issue at hand.

Indeed these more senior folks may already know there is an issue, but may not be aware how apparent or wide it is or indeed want to publicise it necessarily.

Have you any other historic and/or current traceroute and/or ping test results to any of the major hosts that you are experiencing issues with? If you can evidence to VF that there has been a definite step change in performance this would help them to understand there is a deeper problem in their network. The sudden trebling of ping times to your connection are strong evidence.

Hey Rolandrat. Why didnt I think of this! Thank you for responding.

I have a hooky cheap VPN service but the speeds on it have always been poor so I didnt think of using it in this case.

I signed up for Nord tonight and wow! I have consistently not been able to exceed 15Mbps for Apple downloads since this issue started. I have tried Nord at the default London pop and I get 600-700! Firstly I didnt realise Nord got those speeds and more importantly it shows again that my link and the destination is just fine but there is some issue with the route.

I am not sure VF will entertain this as they have been clear that level 3 will not help any further but I think it is excellent to have in hand if it gets to cisas/ofcom.

Thanks again!

Hi and thanks for the help.

Completely agree on the need to speak to a level of support that can have this conversation but I have failed to get that support and they are saying I can only raise with Customer Relations for a complaint now. I also agree it is likely this is known to the network folks somewhere as it would surely show up for more than just me in the net monitoring available these days.

I have indeed got history. I have an instance of smokeping running on my network and I can show the exact change. Let's see if the images come out here:

https://i.imgur.com/9JOlEO0.png
https://i.imgur.com/4GAapDm.png

It shows the pings go from 6 to 12/13 ( doubling, not quite trebling, sorry) on or around April 13th for Google DNS and Youtube.

My challenge remains how to get someone in VF to speak to and do they care.

I'm off to test more links over VPN as that looks to prove the issue is in VF routes somewhere.

I'm not sure this is proving anything if VF wont talk to me but...

Speedtest.net off VPN: https://i.imgur.com/dZqcTVF.png
Speedtest.net on Nord: https://i.imgur.com/XNT3JkH.png

Coincidentally, one of the servers used in the above multi server test is Mythical Beasts in London who host the Raspberry PI OS downloads I have used so frequently. Without VPN, I can get 12 max when downloading an ISO file. With Nord today, I get 500