topic Re: Traffic shaping? Weird Wireguard Behaviour in Full Fibre

Traffic shaping? Weird Wireguard Behaviour

Ping_Too_Long — Fri, 07 Feb 2025 18:15:04 GMT

Had an interestng issue...

Much prefer to control my network and data via Linux CLI. Connecting via Wireguard UDP sees speeds drop massively. Oddly enough, if I can use TCP speeds are good.

I know this from testing via my Windows machines as this isn't an option via Linux CLI. But I am quite frankly appalled and flabbergasted as this totally shady practice from Plusnet. Unfortunately I've signed up for a long deal.

Very disappointed.

Re: Traffic shaping? Weird Wireguard Behaviour

jab1 — Fri, 07 Feb 2025 18:29:10 GMT

@Ping_Too_Long Not really my area of expertise, but Plusnet do not traffic shape. What product are you on, what are the estimated speeds, and what does a site such as https://www.thinkbroadband.com/speedtest or https://www.thinkbroadband.com/speedtest report?

Re: Traffic shaping? Weird Wireguard Behaviour

outcast — Fri, 07 Feb 2025 18:49:35 GMT

Plusnet removed traffic shaping in July 2017 from all customer accounts, unless you specifically signed up for "Plusnet Pro" which was later discontinued in September 2022.

What router are you using ?

Does your Plusnet connection have a static WAN IP, or is it dynamic ?

What MTU is your Wireguard set to ?

Are you connecting both ends of your VPN with your own setup, or are you using Proton VPN (that does interesting things with Wireguard TCP).

Re: Traffic shaping? Weird Wireguard Behaviour

Ping_Too_Long — Fri, 07 Feb 2025 18:53:56 GMT

Outcast, you legend... how did you guess protonvpn?😄

So it's a them thing? Thank you again!

Re: Traffic shaping? Weird Wireguard Behaviour

outcast — Fri, 07 Feb 2025 19:47:20 GMT

"Guess" ? Ha !

I've been doing a lot of reading of all the clever things Proton VPN do, especially Wireguard TCP.

I'm looking at rebuilding my router this year, and want to run permanent Proton VPN endpoints on each of my WAN static IP addresses, to appear remotely in London, Canada, Czech Republic, South Korea, Switzerland, and Russia, then map each of those WAN gateways to separate internal VLANs on my home network. Then using my own internal routing to map each of my family members 'personal' home network VLANs, to the country where they are currently travelling / living. Hopefully this will provide secure connectivity for all of my family, wherever they are, so we can communicate with each other without our data being visible anywhere on the internet, and have access to each of our personal home servers for email and file storage etc.

So far Proton appears to be the ONLY commercial VPN provider that can do what I'm looking to achieve.

Re: Traffic shaping? Weird Wireguard Behaviour

corringham — Sat, 08 Feb 2025 09:35:00 GMT

Try lowering the MTU a bit on your Windows PC.

Using a VPN has an overhead of a few bytes per packet - if that pushes the packet size over the MTU then the packets will (should) be split and reassembled at the other end. Not every network device does this cleanly (or at all). If packets are split and reassembled at the other end there will be a reduction in bandwidth. If packets are not correctly reassembled there will be packet loss and a significant drop in bandwidth.

Depending on your router and VPN, the MTU may need to be as low as 1460, although 1488 is often OK.

Re: Traffic shaping? Weird Wireguard Behaviour

outcast — Sat, 08 Feb 2025 09:53:18 GMT

Proton's WireGuard VPN has a default MTU of 1420 when line MTU is 1500, probably less if using a PPPoE MTU of 1492.

AFAIK the protocol overhead is 60 bytes for IPv4, and 80 for IPv6.

which is why I mentioned MTU in reply #3

Re: Traffic shaping? Weird Wireguard Behaviour

corringham — Sat, 08 Feb 2025 09:48:28 GMT

Thanks for the info - I've never used Proton's Wireguard VPN. Sounds like all the more reason to try lowering the MTU on the Windows PC.