



Network Working Group                                      M. Nottingham
Internet-Draft                                          November 5, 2018
Updates: 3864, 7231 (if approved)
Intended status: Standards Track
Expires: May 9, 2019


                   A Registry for HTTP Header Fields
              draft-nottingham-httpbis-header-registry-00

Abstract

   This document defines a separate IANA registry for HTTP header
   fields, and establishes the procedures for its operation.

Note to Readers

   The issues list for this draft can be found at
   https://github.com/mnot/I-D/labels/httpbis-header-registry [1].

   The most recent (often, unpublished) draft is at
   https://mnot.github.io/I-D/httpbis-header-registry/ [2].

   Recent changes are listed at https://github.com/mnot/I-D/commits/gh-
   pages/httpbis-header-registry [3].

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."

   This Internet-Draft will expire on May 9, 2019.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




Nottingham                 Expires May 9, 2019                  [Page 1]

Internet-Draft            HTTP Header Registry             November 2018


   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.  Notational Conventions  . . . . . . . . . . . . . . . . .   3
   2.  The HTTP Header Field Registry  . . . . . . . . . . . . . . .   3
     2.1.  Requesting Registration . . . . . . . . . . . . . . . . .   3
   3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Registry Creation . . . . . . . . . . . . . . . . . . . .   4
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   5.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   5
     5.1.  Normative References  . . . . . . . . . . . . . . . . . .   5
     5.2.  Informative References  . . . . . . . . . . . . . . . . .   5
     5.3.  URIs  . . . . . . . . . . . . . . . . . . . . . . . . . .   6
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   6

1.  Introduction

   [RFC3864] established common IANA registries for header fields from a
   variety of protocols.  Experience has shown that having a combined
   registry has few benefits, and creates a number of issues, including:

   o  Difficulty in evolving the registration process (without
      coordination with other protocols),

   o  Registry user confusion, due to the large number of header fields
      registered,

   o  Using one expert to review all header field registrations is
      onerous to that individual,

   o  Lack of HTTP community involvement / oversight in reviews.

   While these issues could be mitigated by a RFC3864bis, it is more
   straightforward to separate the HTTP registrations out into a
   separate registry; since there is only slight syntactic similarity
   between header fields between protocols (and often, the mismatches
   create confusion), and little semantic overlap, this seems like the
   best path forward.



Nottingham                 Expires May 9, 2019                  [Page 2]

Internet-Draft            HTTP Header Registry             November 2018


   Therefore, this document establishes a new HTTP Header Field
   Registry, defines its procedures, and guides the transition of
   existing values to it.  Doing so effectively removes HTTP header
   fields from the scope of [RFC3864] and the registries it defines, and
   updates [RFC7231] Section 8.3 with a new process for managing them.

1.1.  Notational Conventions

   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 [RFC2119].

2.  The HTTP Header Field Registry

   The "Hypertext Transfer Protocol (HTTP) Header Field Registry"
   defines the namespace for HTTP header fields (as per [RFC7230],
   Section 3.2).

2.1.  Requesting Registration

   Any party can request registration of a HTTP header field.  See
   [RFC7231] Section 8.3.1 for considerations to take into account when
   creating a new HTTP header field.

   The "HTTP Header Field Name" registry is located at
   "https://www.iana.org/assignments/http-headers/".  Registration
   requests can be made by following the instructions located there or
   by sending an email to the "ietf-http-wg@ietf.org" mailing list.

   Header field names are registered on the advice of a Designated
   Expert (appointed by the IESG or their delegate).  Header fields with
   the status 'permanent' are Specification Required (using terminology
   from [RFC8126]).

   Registration requests consist of at least the following information:

   o  *Header field name*: The requested field name.  It MUST conform to
      the field-name syntax defined in [RFC7230], Section 3.2, and
      SHOULD be restricted to just letters, digits, hyphen ('-') and
      underscore ('_') characters, with the first character being a
      letter.

   o  *Status*: "permanent" or "provisional"

   o  *Author/Change controller*: For a standards-track RFC, state
      "IETF".  For other open standards, give the name of the publishing
      body (e.g., "W3C").  For other specifications, give the name and/




Nottingham                 Expires May 9, 2019                  [Page 3]

Internet-Draft            HTTP Header Registry             November 2018


      or organisation name and e-mail address of the primary
      specification author.

   o  *Specification document(s)*: Reference to the document that
      specifies the header field, preferably including a URI that can be
      used to retrieve a copy of the document.  An indication of the
      relevant section(s) can also be included, but is not required.

   The Expert(s) can define additional fields to be collected in the
   registry, in consultation with the community.

   Standards-defined names have a status of "permanent".  Other names
   can also be registered as permanent, if the Expert(s) find that they
   are in use, in consultation with the community.  Other names should
   be registered as "provisional".

   Provisional entries can be removed by the Expert(s) if - in
   consultation with the community - the Expert(s) find that they are
   not in use.  The Experts can change a provisional entry's status to
   permanent at any time.

   Note that names can be registered by third parties (including the
   Expert(s)), if the Expert(s) determines that an unregistered name is
   widely deployed and not likely to be registered in a timely manner
   otherwise.

3.  IANA Considerations

3.1.  Registry Creation

   IANA will create a new registry as outlined in Section 2.

   After creating the registry, all entries in the Permanent and
   Provisional Message Header Registries with the protocol 'http' are to
   be moved to it, with the following changes applied:

   1.  The 'Applicable Protocol' field is to be omitted.

   2.  Entries with a status of 'standard', 'experimental', or
       'informational' are to have a status of 'permanent'.

   3.  Entries with a status of 'deprecated' are to have a status of
       'obsoleted'.

   4.  Provisional entries without a status are to have a status of
       'provisional'.





Nottingham                 Expires May 9, 2019                  [Page 4]

Internet-Draft            HTTP Header Registry             November 2018


   5.  Permanent entries without a status (after confirmation that the
       registration document did not define one) will have a status of
       'provisional'.  The Expert(s) can choose to update their status
       if there is evidence that another is more appropriate.

   The Permanent and Provisional Message Header registries will be
   annotated to indicate that HTTP header field registrations have
   moved, with an appropriate link.

4.  Security Considerations

   No security considerations are introduced by this specification
   beyond those already inherent in the use of HTTP header fields.

5.  References

5.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC7230]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Message Syntax and Routing",
              RFC 7230, DOI 10.17487/RFC7230, June 2014,
              <https://www.rfc-editor.org/info/rfc7230>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

5.2.  Informative References

   [RFC3864]  Klyne, G., Nottingham, M., and J. Mogul, "Registration
              Procedures for Message Header Fields", BCP 90, RFC 3864,
              DOI 10.17487/RFC3864, September 2004,
              <https://www.rfc-editor.org/info/rfc3864>.

   [RFC7231]  Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
              Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
              DOI 10.17487/RFC7231, June 2014,
              <https://www.rfc-editor.org/info/rfc7231>.







Nottingham                 Expires May 9, 2019                  [Page 5]

Internet-Draft            HTTP Header Registry             November 2018


5.3.  URIs

   [1] https://github.com/mnot/I-D/labels/httpbis-header-registry

   [2] https://mnot.github.io/I-D/httpbis-header-registry/

   [3] https://github.com/mnot/I-D/commits/gh-pages/httpbis-header-
       registry

Author's Address

   Mark Nottingham

   Email: mnot@mnot.net
   URI:   https://www.mnot.net/




































Nottingham                 Expires May 9, 2019                  [Page 6]
