DNS and PREF64 Configuration for Proxying IP in HTTP

Proxying IP in HTTP allows building a VPN through HTTP load balancers. However, at the time of writing, that mechanism lacks a way to communicate network configuration details such as DNS information or IPv6 NAT64 prefixes (PREF64). In contrast, most existing VPN protocols provide mechanisms to exchange such configuration information. This document defines extensions that convey DNS and PREF64 configuration using HTTP capsules. This mechanism supports encrypted DNS transports and can be used to inform peers about network translation prefixes for IPv6/IPv4 synthesis.