DoH Preference Hints for HTTP
draft-schinazi-httpbis-doh-preference-hints-02

Document Type Active Internet-Draft (individual)
Authors David Schinazi  , Nick Sullivan  , Jesse Kipp 
Last updated 2020-07-13
Stream (None)
Intended RFC status (None)
Formats plain text html xml pdf htmlized (tools) htmlized bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group                                        D. Schinazi
Internet-Draft                                                Google LLC
Intended status: Experimental                                N. Sullivan
Expires: 14 January 2021                                         J. Kipp
                                                              Cloudflare
                                                            13 July 2020

                     DoH Preference Hints for HTTP
             draft-schinazi-httpbis-doh-preference-hints-02

Abstract

   When using a publicly available DNS-over-HTTPS (DoH) server, some
   clients may suffer poor performance when the authoritative DNS server
   is located far from the DoH server.  For example, a publicly
   available DoH server provided by a Content Delivery Network (CDN)
   should be able to resolve names hosted by that CDN with good
   performance but might take longer to resolve names provided by other
   CDNs, or might provide suboptimal results if that CDN is using DNS-
   based load balancing and returns different address records depending
   or where the DNS query originated from.  This document attempts to
   lessen these issues by allowing the web server to indicate to the
   client which DoH server can best resolve its addresses.  This
   document defines an HTTP header field that enables web host operators
   to inform user agents of the preferred DoH servers to use for
   subsequent DNS lookups for the host's domain.

   Discussion of this work is encouraged to happen on the ADD IETF
   mailing list add@ietf.org or on the GitHub repository which contains
   the draft: https://github.com/DavidSchinazi/draft-httpbis-doh-
   preference-hints.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

Schinazi, et al.         Expires 14 January 2021                [Page 1]
Internet-Draft            DoH Preference Hints                 July 2020

   This Internet-Draft will expire on 14 January 2021.

Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Simplified BSD License text
   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Conventions and Definitions . . . . . . . . . . . . . . .   3
   2.  The DoH-Preference Header Field . . . . . . . . . . . . . . .   3
     2.1.  The max-age Directive . . . . . . . . . . . . . . . . . .   4
     2.2.  Examples  . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Server Behavior . . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Considerations For Choosing a Preferred DoH Server  . . .   4
   4.  Client Behavior . . . . . . . . . . . . . . . . . . . . . . .   5
     4.1.  Fallback  . . . . . . . . . . . . . . . . . . . . . . . .   5
   5.  Internationalization Considerations . . . . . . . . . . . . .   5
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   6
   8.  Normative References  . . . . . . . . . . . . . . . . . . . .   6
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .   7
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   7

1.  Introduction

   When using a publicly available DNS-over-HTTPS (DoH) server, some
   clients may suffer poor performance when the authoritative DNS server
   is located far from the DoH server.  For example, a publicly
   available DoH server provided by a Content Delivery Network (CDN)
   should be able to resolve names hosted by that CDN with good
   performance but might take longer to resolve names provided by other
   CDNs, or might provide suboptimal results if that CDN is using DNS-
   based load balancing and returns different address records depending
   or where the DNS query originated from.  This document attempts to
Show full document text