Your network contains an Active Directory domain.
You plan to implement a remote access solution that will contain three servers that run Windows Server
2012. The servers will be configured as shown in the following table.

Server1 will support up to 200 concurrent VPN connections.
You need to ensure that all VPN connection requests are authenticated and authorized by either Server2
or Server3. The solution must ensure that the VPN connections can be authenticated if either Server2 or
Server3 fails.
What should you do?

A.
On Server1, configure a RADIUS proxy. On Server2 and Server3, add a RADIUS client.

B.
On Server2 and Server3, add a RADIUS client. On Server1, modify the Authentication settings.

C.
On Server1, configure a RADIUS proxy. Add Server2 and Server3 to a failover cluster.

D.
Add Server2 and Server3 to a Network Load Balancing (NLB) cluster. On Server1, modify the
Authentication settings.

Explanation:
* A network access server (NAS) is a device that provides some level of access to a larger network. A NAS
using a RADIUS infrastructure is also a RADIUS client, sending connection requests and accounting
messages to a RADIUS server for authentication, authorization, and accounting.
* Client computers, such as wireless portable computers and other computers running client operating
systems, are not RADIUS clients. RADIUS clients are network access servers—such as wireless access
points, 802.1X-capable switches, virtual private network (VPN) servers, and dial-up servers—because
they use the RADIUS protocol to communicate with RADIUS servers such as Network Policy Server (NPS)
servers.
RADIUS Client
http://technet.microsoft.com/en-us/library/cc754033.aspx