DNS over HTTPS (DoH) on iOS 18: A Comprehensive Guide

With the release of iOS 18 (assuming this is a future iOS version, as of October 26, 2023, it doesn't exist), Apple may or may not introduce significant changes to its handling of DNS over HTTPS (DoH). This guide explores the current state of DoH on iOS and speculates on potential features in a hypothetical iOS 18.

What is DNS over HTTPS (DoH)?

DNS over HTTPS (DoH) is a method of encrypting DNS lookups, improving privacy and security. Traditionally, DNS queries are sent in plain text, making them vulnerable to eavesdropping and manipulation. DoH encapsulates these queries within an HTTPS connection, providing confidentiality and integrity.

DoH on Current iOS Versions

As of the latest iOS versions, Apple offers limited built-in support for DoH. While not explicitly labeled as DoH, Apple's private DNS feature allows users to specify a custom DNS resolver that *may* support DoH. However, this isn't guaranteed; the resolver needs to explicitly support it. Many popular privacy-focused DNS providers (like Cloudflare, Google Public DNS, Quad9) offer DoH, and using one of them with iOS's private DNS setting effectively enables DoH-like functionality.

Potential DoH Enhancements in a Hypothetical iOS 18

If Apple were to improve DoH support in iOS 18, several features could be introduced:

• Built-in DoH support with a system-wide toggle: A simple on/off switch in settings to enable DoH for all apps and network traffic, using a default Apple-approved resolver or allowing users to select a preferred provider.
• Improved DoH provider selection: A more intuitive interface for selecting and managing DoH providers, with clearer explanations of the privacy implications and features of each provider.
• Enhanced privacy controls: More granular control over which apps use DoH, allowing users to selectively enable or disable it for specific applications.
• Support for DNS-over-QUIC (DoQ): This newer protocol builds on DoH to offer even faster and more efficient DNS lookups.
• Integration with other privacy features: Seamless integration with other privacy-focused features in iOS, like Private Relay.
• Enhanced security features: Protection against DNS spoofing and other attacks using DoH's security features.

How to Use DoH on Current iOS Versions (Approximation of what might work on iOS 18)

1. Go to Settings > Wi-Fi.
2. Tap the “i” icon next to your connected network.
3. Scroll down and tap “Configure DNS.”
4. Choose “Manual.”
5. Enter the IP addresses or domain names of your chosen DoH provider. For example, for Cloudflare, you might use 1.1.1.1 and 1.0.0.1.
6. Save your settings.

Important Note: Always verify the reputation and security practices of any DNS provider before using it.

Troubleshooting

If you encounter issues after configuring DoH, try the following:

• Restart your device.
• Verify the IP addresses or domain names you entered are correct.
• Check your network connection.
• Contact your DoH provider’s support for assistance.

Conclusion

While iOS currently offers a pathway to utilizing DoH-like functionality, a more native and integrated approach in a future iOS 18 could significantly boost user privacy and security. This guide provides a solid foundation for understanding DoH and how it might evolve in the future.