http-source-information-header

A Draft IETF RFC

• draft-levy-edns0-subnet-zero-via-mapped-addressing

This document proposes a way to use EDNS0 client-subnet (ECS) without exposing the end users IP address. This can be used to approximatly identify which geographic-location the client is located.

Presently RFC7871 simply states that a DNS resolver should truncate the clients IP address.

To protect users' privacy, Recursive Resolvers are strongly encouraged to conceal part of the user's IP address by truncating IPv4 addresses to 24 bits. 56 bits are recommended for IPv6, based on [RFC6177].

This proposal allocates an IPv6 block and publishes a geographic mapping of the client IP address into a pre-defined IPv6 address within that block.

Goals

The goal is simple. Never return the IP (or IP block) of the client; but instead map the location (which the resolver calculates from the client IP) into a meta-IP address. Meanwhile, there exists a table that's public (and distributed to geolocation companies and users) which maps this meta-IP to a location.

building txt and html files

This is done with the Makefile.

• xml2rfc -N --text draft-levy-edns0-subnet-zero-via-mapped-addressing.xml
• xml2rfc -N --html draft-levy-edns0-subnet-zero-via-mapped-addressing.xml

You will need xml2rfc installed.

pip install xml2rfc

Authors

• Martin J. Levy @ Cloudflare