Overview of Solutions for Managing Internet-based Windows 8.1 Devices

          Clients that connect from the Internet can provide unique challenges for administrators. Windows 8.1 and Windows Server® 2012 R2 provide several options for enabling greater management control of Windows 8.1 computers that are connected to the Internet, but are not directly connected to your internal network.

VPN
VPN connectivity has been a long-standing
connectivity option for Internet-based clients.
VPN enables a client to connect to an internal
network by using a VPN server, which typically is located in a perimeter network. Through VPN, a client user authenticates to a network environment and can gain access to network resources. VPN connections provide a very limited scope of management. Common configuration management methods like Group Policy typically do not function over a VPN connection.

DirectAccess
           DirectAccess takes the concept of VPN and uses Windows Server 2012 R2 technology to enable an Internet-based client to connect to a domain controller on an internal network, authenticate a client computer account, and accept sign-ins from users as if the client computer is connected to the internal network. Because the appropriate authentication has been performed, you can manage DirectAccess clients by using Group Policy, and they appear to other enterprise management systems as if they were connected to the internal network.