How to enable TCP BBR on Windows?

Question

TCP BBR can be enabled in linux using the following commands:

net.core.default_qdisc=fq
net.ipv4.tcp_congestion_control=bbr

as explained here

How do you do the same on a Windows 10 machine?

Caritta

Answer 1

Works on Windows 11 22H2

netsh int tcp set supplemental Template=Internet CongestionProvider=bbr2
netsh int tcp set supplemental Template=Datacenter CongestionProvider=bbr2
netsh int tcp set supplemental Template=Compat CongestionProvider=bbr2
netsh int tcp set supplemental Template=DatacenterCustom CongestionProvider=bbr2
netsh int tcp set supplemental Template=InternetCustom CongestionProvider=bbr2

Get-NetTCPSetting | Select SettingName, CongestionProvider

Gibe

Setting the congestion provider to BBR2 currently breaks Hyper-V's local console connection (as of Windows 11 23H2). The console will show "Connecting to '[VM]'" for some minutes before failing with "Video remoting was disconnected" with a popup "Could not connect to the virtual machine." – Abandon

Answer 2

The linux kernel ships with a few built-in congestion-controllers and can load additional ones via kernel modules, so 3rd parties can provide custom ones.

I'm not aware of a mechanism that allows custom congestion controllers to be shipped for windows, so you can only use the ones provided by microsoft. Windows 10 does offer a few alternatives covering different use-cases besides the default one, e.g. CTCP and LEDBAT.

So you'll have to evaluate the available ones by the same criteria that made you choose BBR under linux.

Squat

Windows 11 22H2 supports BBR (with name bbr2) which is a congestion algorithm that tries to optimize for high bandwidth (bitrate) without sacrifying latency similar to CUBIC (which only optimizes for highest possible bandwidth). LEDBAT optimizes for low latency but will slow down against any competing traffic. If you don't have BBR support for your version of windows, CTCP is probably the least bad option to use instead of BBR. I personally think both CDG and Vegas are better algorithms (have lower latency, especially with fiber connections) than BBR but Windows supports neither. – Mesdames