When this policy setting is enabled, a secure channel can only be established with domain controllers that are capable of encrypting secure channel data with a strong (128-bit) session key. To enable this policy setting, all domain controllers in the domain must be able to encrypt secure channel data with a strong key, which means all domain controllers must be running Microsoft Windows 2000 or later. If communication to non-Windows 2000based domains is required, it is recommended that you disable this policy setting.