Choose an Authentication Method
Applies To: Windows Server 2008, Windows Server 2008 R2
For site-to-site connections, you must implement user-level authentication, and, for greater security, you might decide to implement computer-level authentication as well:
User-Level Authentication for PPTP and L2TP/IPsec site-to-site connection types
Computer-Level Authentication for L2TP/IPsec connections only