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Network Policy and Access Services

Network Policy and Access Services (NPAS) helps you safeguard the health and security of your network. The NPAS server role includes Network Policy Server (NPS), Health Registration Authority (HRA), and Host Credential Authorization Protocol (HCAP).

NPS allows you to provide local and remote network access and to define and enforce policies for network access authentication, authorization, and—when you deploy Network Access Protection (NAP) —client health. HRA is a feature of NPS used when you deploy NAP, and HCAP provides NAP  interoperability with Network Access Control (NAC), the Cisco client health solution.

In Windows Server 2003, Internet Authentication Service (IAS) is the Microsoft implementation of a Remote Authentication Dial-In User Service (RADIUS) server. In Windows Server operating systems later than Windows Server 2003, IAS is renamed to NPS.

Featured Resources

Resources for Windows Server 2012,
Windows Server 2008 R2,
and Windows Server 2008

Deployment Resources

DirectAccess with NAP

Interoperability Resources

Troubleshooting Resources

Solution Accelerators

Internet Authentication Service for Windows Server 2003


Networking at a Glance

Networking Technologies

Frequently Asked Questions