BBRv2Disable.ps1

<#
.SYNOPSIS
   Disable BBRv2 as the TCP congestion provider

.DESCRIPTION
   Disable BBRv2 as the TCP congestion provider

.NOTES
   Created by Jauder Ho
   Last modified 11/1/2019
   https://www.carumba.com

   BSD License

   Pull requests are welcome.

.LINK
   https://docs.microsoft.com/en-us/azure/active-directory/hybrid/reference-connect-tls-enforcement
   https://jorgequestforknowledge.wordpress.com/category/windows-azure-active-directory/azure-ad-application-proxy-connector/
   https://support.microsoft.com/en-us/help/3135244/tls-1.2-support-for-microsoft-sql-server
   https://www.hass.de/content/setup-your-iis-ssl-perfect-forward-secrecy-and-tls-12
   https://msdn.microsoft.com/en-us/library/aa374757(VS.85).aspx
   https://blogs.technet.microsoft.com/askpfeplat/2017/11/13/demystifying-schannel/
   https://support.microsoft.com/en-us/help/3140245/update-to-enable-tls-1-1-and-tls-1-2-as-default-secure-protocols-in-wi
#>

# Elevate as needed
# https://superuser.com/questions/108207/how-to-run-a-powershell-script-as-administrator
param([switch]$Elevated)

function Test-Admin {
   $currentUser = New-Object Security.Principal.WindowsPrincipal $([Security.Principal.WindowsIdentity]::GetCurrent())
   $currentUser.IsInRole([Security.Principal.WindowsBuiltinRole]::Administrator)
}

if ((Test-Admin) -eq $false) {
   if ($elevated) {
      # tried to elevate, did not work, aborting
   }
   else {
      Start-Process powershell.exe -Verb RunAs -ArgumentList ('-noprofile -noexit -file "{0}" -elevated' -f ($myinvocation.MyCommand.Definition))
   }

   exit
}

Write-Output 'Running with full privileges...'

function Disable-BBRv2 {
   netsh int tcp set supplemental template=internet congestionprovider=CUBIC
   netsh int tcp set supplemental template=internetcustom congestionprovider=CUBIC
   netsh int tcp set supplemental template=Compat congestionprovider=NewReno
   netsh int tcp set supplemental template=Datacenter congestionprovider=CUBIC
   netsh int tcp set supplemental template=Datacentercustom congestionprovider=CUBIC

   Set-NetTCPSetting -SettingName "Internet" -CongestionProvider Cubic
   Set-NetTCPSetting -SettingName "Datacenter" -CongestionProvider Cubic
   Set-NetTCPSetting -SettingName "Compat" -CongestionProvider NewReno
   Set-NetTCPSetting -SettingName "InternetCustom" -CongestionProvider Cubic
   Set-NetTCPSetting -SettingName "DatacenterCustom" -CongestionProvider Cubic

   Write-Output 'BBRv2 has been disabled'
}

Disable-BBRv2