topic FTTP dropping packets above 20ms when using battlenet and other gaming CDNs in Full Fibre

FTTP dropping packets above 20ms when using battlenet and other gaming CDNs

DaddyOfDuty — Mon, 01 Dec 2025 21:35:47 GMT

I've had a ongoing issue since install nearly 2 years ago regarding packet loss mainly noticable when download game updates from battle.net or epic games content delivery servers.

I tried reporting the issue to customer service but they didn't understand. They arranged a Cube engineer at the time and 2 guys came out saw the issue and couldn't offfer any fix or quite understand what i was showing them. I showed the issue by using the plusnet router and also directly with a laptop setup direct to the ONT using PPPOE.

The connection and latency are generally great but as soon as an update is needed for a game the whole connection appears to act like a DDOS, all internet traffic and devices will suffer packet loss until the download is complete. We have a few gamers in the house so its starting to annoy other users now. I would expect the latency to jump higher as the connection is saturated not drop packets above 20ms.

I've factory reset the ONT, tried multiple routers (currently a Draytek 2865) and direct to the ONT with PPPOE. Upgraded from 500mb to 900mb. Tried QOS, TCP ACK priority, limiting download speed but unfortunately cant resolve it.

The think broadband graph always shows a hard cut off around 20ms and packet loss when it happens.

How can I reach the correct person at Plusnet to help?

Re: FTTP dropping packets above 20ms when using battlenet and other gaming CDNs

corringham — Mon, 01 Dec 2025 22:03:24 GMT

One thing worth trying is to to lower the MTU setting on your computer - I'd suggest trying 1420, but there are commands that will display the MTU for a given path (depending on your OS).

MTU is the maximum transmission unit which is the maximum packet size that can be transmitted for a particular path - it can vary depending on t he devices along the way. Ethernet has a default MTU of 1500, but if you use a VPN, or any other form of encapsulation then that uses some of the size leaving less for your data.

If MTU is exceeded then the packet will be split into smaller packets - while this is built into the standards a lot of devices are very bad at this, and quite a few mess up and drop packets. A symptom of this is very poor throughput on a connection that is otherwise OK.

You problem may not be MTU related, but is worth ruling it out.

Re: FTTP dropping packets above 20ms when using battlenet and other gaming CDNs

DaddyOfDuty — Tue, 02 Dec 2025 19:39:05 GMT

Hi, I previously tried a few different MTUs but i gave 1420 a whirl but had the same result. The longer packetloss spikes near the end of the graph is me rebooting the router to make the change.

This is different gaming pc updating from battlenet also causing the packetloss. The PCs are all wired by the way.

I think its a change needed at plusnet but I can't seem to raise the issue to anyone that does more than run an openreach test (which obviously passes)