Increase Concurrent Authentications Processed by NPS

Applies to: Windows Server 2022, Windows Server 2019, Windows Server 2016

You can use this topic for instructions on configuring Network Policy Server concurrent authentications.

If you installed Network Policy Server (NPS) on a computer other than a domain controller and the NPS is receiving a large number of authentication requests per second, you can improve NPS performance by increasing the number of concurrent authentications allowed between the NPS and the domain controller.

To do this, you must edit the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters

Add a new DWORD value named MaxConcurrentApi and assign to it a value of 150.

Caution

If you assign a value to MaxConcurrentApi that is too high, your NPS might place an excessive load on your domain controller.

For more information about MaxConcurrentApi, see How to do performance tuning for NTLM authentication by using the MaxConcurrentApi setting

For more information about managing NPS, see Manage Network Policy Server.

For more information about NPS, see Network Policy Server (NPS).