Right I have now swap from Cat 6A to Cat 5E from ONT to Router (hope it fixed the issues)

I got to wait until 12:30pm to give the graph more time and do one large download from ThinkBroadband 5GB to see if it stop the spiked with red packet loss.

Edited by adslmax (Sun 18-Jan-26 12:16:24)

In reply to a post by seb:

Try doing a manual download of a very large file:
https://www.thinkbroadband.com/download

Then wait enough to get a graph on the graph (5 mins say).
Then try to upload that file somewhere you know is able to get reasonable speed.

This allows you to separate the download/upload bit.. I think upload is more likely to cause those issues.

If you max out a line there's buffering.. and that causes latency to spike. How much depends a bit on the way the router works (how it prioritises things, how big the buffers are) and the large download and how it manages data flow (may vary by OS etc).. I'm not really an expert in that level of detail to say how it would react but I'd confirm the download vs upload issue.

seb

What a nightmare! 5GB download file from IPv4 port 80 take nearly 8 minutes but don't know why it capped at 97.9Mbps see screenshot:
https://image2url.com/r2/default/images/176873993998...

Just ran speedtest (look like Cat 5e cable strict to 100Mbps!) from ONT to Router. I have to find other spare Cat 5E cable again.

Why do you think it's the cable?

In reply to a post by broadband66:

Why do you think it's the cable?

Swapped to other cable cat5e and it now back to 1Gbps. Silly me the other cable isn't 5E it was Cat5 without e on it.

I will run another download 5GB file from TBB at 2pm.

Edited by adslmax (Sun 18-Jan-26 13:13:12)

Have you disabled automatic updates on how ever many xboxes are on your network.

I have disabled all WiFi and just ont and my PC for now. Told her she have to use G.fast for now. Until get this resolved with spiked area.

Will try TTB 5GB test file at 2pm to see if there still any spiked on it after swapped cat5e cable instead of cat 6a cable as Sebastian think it very dodgy one.

In reply to a post by seb:

If it was your problem we'd see the same pattern on a load of graphs too. Which we don't.

Cheers on the clarity on this seb.

Right here is the 5GB test file from TTB using ethernet CAT 5E cable from ONT to PC direct with all wifi disabled and no other device as it was removed off.

Look like much better 110Mb/s download transfer speed 40 secs to completed.

https://image2url.com/r2/default/images/176874496118...

However, the TTB BQM graph has finally showing NO SPIKED at 2pm just after downloaded 5GB single file.
https://www.thinkbroadband.com/broadband/monitoring/...


Congrats Seb, you are 100% correct it was dodgy Cat6A flat cable from TP Link are terrible, just awful.

It's all FIXED now!

Without your help I would stuck with lots of spiked with Cat 6A flat cable (that now going in the bin)

Also, finally. Apology to Martin not the ISP at all. It was all my dodgy bad ethernet cable from the start!

Hopefully the spiked disappear now when I put all other devices and WiFi back on!

In reply to a post by adslmax:

I just done one single speedtest just before 12pm today you can see large spiked 160ms with one red packet loss

I've just done a speed test both on a 1Gbps Ethernet connection (1G symmetric; may have other traffic so not trying to max it out on this one test per se) and it's a tiny blip on the graph.. a few ms yellow increase at most.

On an FTTC line I did the same (on wi-fi but shouldn't matter here) and I see a much more noticeable spike.. taken from BQM CSV converted from ns to ms and min/average/max:

4.9 5.4 5.9
4.9 8.8 38.1
4.8 5.6 9.2


You can see the max spikes from 6-9ms to 38ms. The test isn't thast long so the average spikes much less (from around 5.5ms to 8.8ms). Each row is 100 seconds.. if I maxed out download it would increase the max.

You might be able to improve latency by using some kind of QoS on your router if it supports it if latency matters (enabling it could slightly increase min latency sometimes but it may be more consistent).. it could slow down some things to protect latency-sensitive applications. The chances are the upload has a bigger impact.


seb

Please igorne 12pm look at the one at 2pm