Securing Your Intune Managed Devices with DNS over HTTPS (DoH): A Comprehensive Guide

DNS over HTTPS (DoH) is a privacy-enhancing protocol that encrypts DNS queries, shielding your device's browsing activity from potential eavesdroppers and improving overall security. Integrating DoH with Microsoft Intune allows you to leverage its benefits across your managed devices, offering enhanced protection and control.

Understanding the Benefits of DoH in an Intune Environment

Implementing DoH within your Intune managed environment provides several key advantages:

• Enhanced Privacy: DoH encrypts DNS queries, preventing network observers from seeing which websites your users visit. This is crucial for protecting sensitive data and maintaining user privacy, especially in public Wi-Fi settings.
• Improved Security: By encrypting DNS traffic, DoH mitigates the risk of DNS spoofing and other DNS-based attacks. This strengthens your overall security posture and protects against malicious websites.
• Consistent Policy Enforcement: Intune allows you to centrally manage and enforce DoH settings across your devices, ensuring that all your managed devices benefit from this enhanced security measure. This avoids inconsistencies and simplifies management.
• Bypass Network-Level Restrictions: In certain scenarios, DoH can help users bypass network-level restrictions that might be interfering with legitimate access to web resources. However, this should be carefully considered and managed to prevent misuse.

Implementing DoH with Intune: Strategies and Considerations

There's no single, built-in DoH configuration within Intune. The implementation depends on how you manage your DNS infrastructure and the capabilities of your devices' operating systems. Here are some common strategies:

1. Using a DoH-Compatible DNS Provider:

Most major DNS providers (like Cloudflare, Google Public DNS, Quad9) offer DoH support. You can configure your Intune devices to use these providers through various methods, depending on your OS and network setup. This might involve:

• Configuring the DNS settings directly on the device (less desirable for management): This approach lacks centralized management and might require manual updates on each device.
• Using a VPN or Proxy with built-in DoH support: A corporate VPN solution can be configured to use DoH, providing a more centralized approach.
• Deploying a Custom Configuration Profile (Recommended): This method enables the most controlled and centralized management of DoH within Intune. You can create a custom configuration profile specifying the DoH server address and other necessary settings, ensuring consistency across all devices. This usually involves modifying device-specific settings such as the system's network configuration.

2. Deploying a Private DoH Server:

For organizations with higher security needs or specific requirements, deploying a private DoH server within your own infrastructure offers increased control and better integration with existing security systems. This approach requires more technical expertise but provides more granular control over DNS traffic.

3. Challenges and Considerations:

• Network Compatibility: Ensure your network infrastructure is compatible with DoH. Some firewalls or network devices might block DoH traffic if not properly configured.
• Performance: While DoH improves security, it might introduce slight performance overhead. Monitor network performance after implementation to identify any potential issues.
• Logging and Auditing: Consider how you'll log and audit DNS activity, as the encryption in DoH hides the actual DNS queries from standard network monitoring tools.
• Application Compatibility: While rare, certain applications might not work correctly with DoH. Thorough testing is recommended before widespread deployment.

Conclusion

Implementing DNS over HTTPS through Intune provides significant benefits in terms of security and privacy. Carefully consider your organization's needs and infrastructure when choosing an implementation strategy, weighing the trade-offs between centralized control, ease of deployment, and the complexity of setting up a private DoH server. Remember to thoroughly test and monitor the effectiveness of your DoH deployment to ensure it enhances your security posture without introducing performance issues.