Authors: WafaTech Team

Introduction

In today’s increasingly digital landscape, securing network infrastructure is paramount. For organizations that require secure access for mobile users, wireless clients, and remote VPN connections, the Network Policy Server (NPS) in Windows Server provides a flexible framework. By implementing secure NPS configurations, companies can ensure that only authenticated users and devices can access their networks.

This article outlines the steps to implement secure NPS configurations and highlights best practices for maintaining a robust security posture.

What is Network Policy Server (NPS)?

Network Policy Server (NPS) is Microsoft’s implementation of RADIUS (Remote Authentication Dial-In User Service) and acts as a centralized authentication, authorization, and accounting (AAA) solution for users accessing your network. It can manage access control for both wired and wireless connections, providing a powerful tool for IT administrators.

Key Features of NPS

  • Authentication: NPS supports various authentication protocols, including EAP, PEAP, and MSCHAPv2.

  • Policy Management: Create policies for controlling access to network resources.

  • Accounting: Track user access to monitor usage patterns.

Prerequisites for NPS Installation

Before implementing NPS, ensure the following prerequisites are met:

  1. Operating System: Ensure you have Windows Server 2012 or later.

  2. Active Directory: NPS requires integration with Active Directory for user accounts.

  3. RADIUS Clients: Configure devices that will communicate with the NPS server.

  4. Network Infrastructure: Ensure your network supports the desired authentication method (e.g., WPA2/WPA3 for wireless).

Implementation Steps

Step 1: Install NPS Role

  1. Open Server Manager.

  2. Click on Add Roles and Features.

  3. Select Network Policy and Access Services.

  4. Follow the prompts to complete the installation.

Step 2: Register NPS in Active Directory

  1. Open the NPS Console (Administrative Tools > Network Policy Server).

  2. Right-click on NPS (Local) and select Register server in Active Directory.

  3. Confirm the registration; this process allows NPS to read user accounts.

Step 3: Configure RADIUS Clients

  1. In the NPS console, expand RADIUS Clients and Servers.

  2. Right-click on RADIUS Clients and select New.

  3. Provide a friendly name for your RADIUS client (e.g., wireless access point) and the IP address.

  4. Set a shared secret that will be used by the RADIUS client for authentication.

Step 4: Create Connection Request Policies

  1. In the NPS console, expand Policies and click on Connection Request Policies.

  2. Right-click and select New. Name the policy and specify conditions under which the policy applies.

  3. Configure the settings to allow for RADIUS authentication, specifying the authentication method.

  4. Ensure to specify the NPS server as the destination server for requests.

Step 5: Configure Network Policies

  1. Navigate to Policies > Network Policies.

  2. Right-click and select New to create a policy.

  3. Set conditions for this policy, such as Windows Group, and specify the corresponding permissions.

  4. Define the constraints (e.g., time of day, day of the week) and settings such as encryption and session timeout.

Step 6: Configure Logging and Accounting

  1. In the NPS console, go to the Log File section.

  2. Configure how NPS will log events and specify a location for log files.

  3. Set up monitoring tools to analyze the log data for unusual activities.

Best Practices

  1. Use Strong Authentication Protocols: Implement protocols like PEAP (Protected Extensible Authentication Protocol) with EAP-TLS for certificate-based authentication.

  2. Regularly Update Security Policies: Periodically review network policies against current security threats and best practices.

  3. Implement Network Access Control (NAC): Use NAC to ensure devices comply with your security standards before granting network access.

  4. Employ Two-Factor Authentication (2FA): Combine something the user knows (password) with something the user has (e.g., a mobile device) for enhanced security.

  5. Monitor NPS Logs Regularly: Set up alerts for any suspicious activities, and make use of log analysis tools to help identify patterns and anomalies.

Conclusion

Implementing secure configurations for Network Policy Server (NPS) is essential for protecting sensitive data and maintaining the integrity of your network. By following the steps and best practices detailed in this article, you can ensure a secure environment where only authorized users can access vital resources. Regular reviews and updates to your network policies and practices will help you stay resilient against evolving security threats.

For more insights into securing your network infrastructure and other IT-related topics, stay tuned to WafaTech Blogs.

Disclaimer: The article is for educational purposes only. Always ensure to back up your systems and perform thorough testing before implementing changes in a production environment.