Network Working Group                                          P. Spacek
Internet-Draft                                                    CZ.NIC
Intended status: Standards Track                          O. Gudmundsson
Expires: November 30, 2018                                    Cloudflare
                                                                 O. Sury
                                                                     ISC
                                                            May 29, 2018


                  Minimal EDNS compliance requirements
                    draft-spacek-edns-camel-diet-01

Abstract

   DNS responders must either follow RFC 6891 by fully implementing EDNS
   or at least respond to queries containing OPT record according to
   older specifications.  Non-compliant implementations which do not
   respond at all are not worth talking to.

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
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   This Internet-Draft will expire on November 30, 2018.

Copyright Notice

   Copyright (c) 2018 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
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   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
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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  The Protocol  . . . . . . . . . . . . . . . . . . . . . . . .   2
   3.  Security Considerations . . . . . . . . . . . . . . . . . . .   2
   4.  Privacy Considerations  . . . . . . . . . . . . . . . . . . .   2
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   3
   6.  Normative References  . . . . . . . . . . . . . . . . . . . .   3
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   3

1.  Introduction

   Neither the original DNS standard RFC 1035 nor its extensions RFC
   2671 and RFC 6891 allow not to respond to a DNS query.  Many years
   later non-compliant implementations which drop queries still exist
   and cause lot of extra queries, latency, and complicated logic in
   recursive resolvers.  The cost of supporting these non-compliant
   implementations keeps increasing.

1.1.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119.

2.  The Protocol

   No DNS response message to a repeated DNS query containing EDNS
   extension implies that the other side is not a DNS responder.  The
   querier MUST NOT retry its query without EDNS.

3.  Security Considerations

   Instruction to follow EDNS standard does not change security
   properties beyond what is written in RFC 6891.

4.  Privacy Considerations

   This has no effect on privacy of DNS.








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5.  IANA Considerations

   [Note to IANA, to be removed prior to publication: there are no IANA
   considerations stated in this version of the document.]

6.  Normative References

   [RFC1035]  Mockapetris, P., "Domain names - implementation and
              specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
              November 1987, <https://www.rfc-editor.org/info/rfc1035>.

   [RFC2671]  Vixie, P., "Extension Mechanisms for DNS (EDNS0)",
              RFC 2671, DOI 10.17487/RFC2671, August 1999,
              <https://www.rfc-editor.org/info/rfc2671>.

   [RFC6891]  Damas, J., Graff, M., and P. Vixie, "Extension Mechanisms
              for DNS (EDNS(0))", STD 75, RFC 6891,
              DOI 10.17487/RFC6891, April 2013,
              <https://www.rfc-editor.org/info/rfc6891>.

Authors' Addresses

   Petr Spacek

   Email: petr.spacek@nic.cz


   Olafur Gudmundsson

   Email: olafur+ietf@cloudflare.com


   Ondrej Sury

   Email: ondrej@isc.org
















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