The December 2007 TechNet Cable Guy article in TechNet magazine, "Network Policy Server," describes the new features of Network Policy Server (NPS) in Windows Server 2008. NPS is the replacement for the Internet Authentication Service (IAS) in Windows Server 2003. NPS allows a computer running Windows Server 2008 to act as a Remote Authentication Dial-In User Service (RADIUS) server and proxy. NPS includes many enhancements to facilitate deployment of authenticated network access, to provide extensibility for third-party components, and to support the latest networking technologies and platforms. 
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