Using JSContact in Registration Data Access Protocol (RDAP) JSON Responses
draft-ietf-regext-rdap-jscontact-03

Registration Protocols Extensions                            M. Loffredo
Internet-Draft                                       IIT-CNR/Registro.it
Intended status: Standards Track                                G. Brown
Expires: 25 April 2022                              CentralNic Group plc
                                                         22 October 2021

    Using JSContact in Registration Data Access Protocol (RDAP) JSON
                               Responses
                  draft-ietf-regext-rdap-jscontact-03

Abstract

   This document describes an RDAP extension which represents entity
   contact information in JSON responses using JSContact.

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 25 April 2022.

Copyright Notice

   Copyright (c) 2021 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
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   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Rationale . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.2.  Conventions Used in This Document . . . . . . . . . . . .   3
   2.  JSContact . . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Using JSCard objects in RDAP Responses  . . . . . . . . . . .   4
     3.1.  RDAP Query Parameters . . . . . . . . . . . . . . . . . .   8
   4.  Transition Considerations . . . . . . . . . . . . . . . . . .   8
     4.1.  RDAP Features Supporting a Transition Process . . . . . .   8
       4.1.1.  Notices and Link Relationships  . . . . . . . . . . .   8
       4.1.2.  rdapConformance Property  . . . . . . . . . . . . . .   8
       4.1.3.  Query Parameters  . . . . . . . . . . . . . . . . . .   8
     4.2.  Transition Procedure  . . . . . . . . . . . . . . . . . .   9
       4.2.1.  Transition Stages . . . . . . . . . . . . . . . . . .   9
         4.2.1.1.  Stage 1: only jCard provided  . . . . . . . . . .   9
         4.2.1.2.  Stage 2: jCard sunset . . . . . . . . . . . . . .   9
         4.2.1.3.  Stage 3: jCard deprecation  . . . . . . . . . . .  10
         4.2.1.4.  Stage 4: jCard deprecated . . . . . . . . . . . .  12
         4.2.1.5.  Length  . . . . . . . . . . . . . . . . . . . . .  12
         4.2.1.6.  Goals . . . . . . . . . . . . . . . . . . . . . .  12
   5.  Implementation Status . . . . . . . . . . . . . . . . . . . .  13
     5.1.  IIT-CNR/Registro.it . . . . . . . . . . . . . . . . . . .  13
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  14
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Appendix A.  Change Log . . . . . . . . . . . . . . . . . . . . .  16
     A.1.  Change from 00 to 01  . . . . . . . . . . . . . . . . . .  16
     A.2.  Change from 01 to 02  . . . . . . . . . . . . . . . . . .  16
     A.3.  Change from 02 to 03  . . . . . . . . . . . . . . . . . .  17
     A.4.  Change from 03 to 04  . . . . . . . . . . . . . . . . . .  17
     A.5.  Initial WG version  . . . . . . . . . . . . . . . . . . .  17
     A.6.  Change from 00 to 01  . . . . . . . . . . . . . . . . . .  17
     A.7.  Change from 01 to 02  . . . . . . . . . . . . . . . . . .  17
     A.8.  Change from 02 to 03  . . . . . . . . . . . . . . . . . .  17
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

   This document specifies an extension to the Registration Data Access
   Protocol (RDAP) that allows RDAP servers to use JSContact
   ([draft-ietf-jmap-jscontact]) to represent the contact information
   associated with entities in RDAP responses, instead of jCard
   ([RFC7095]).  It also describes the process by which an RDAP server
   can transition from jCard to JSContact.  RDAP query and response
   extensions are defined to facilitate the transition process.

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1.1.  Rationale

   According to the feedback from RDAP Pilot Working Group
   ([RDAP-PILOT-WG], a group of RDAP server implementers representing
   registries and registrars of generic TLDs), the most commonly raised
   implementation concern, for both servers and client implementers,
   related to the use of jCard ([RFC7095]) to represent the contact
   information associated with entities.  Working Group members reported
   jCard to be unintuitive, complicated to implement for both clients
   and servers, and incompatible with best practices for RESTful APIs.

   JSContact ([draft-ietf-jmap-jscontact]) provides a simpler and more
   efficient representation for contact information.  In addition,
   similarly to jCard, it provides a means to represent
   internationalised and unstructured contact information.  Support for
   internationalised contact information has been recognised being
   necessary to facilitate the future internationalisation of
   registration data directory services.

1.2.  Conventions Used in This Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

2.  JSContact

   The JSContact specification defines a data model and JSON
   representation of contact information that can be used for data
   storage and exchange in address book or directory applications.  It
   aims to be an alternative to the vCard data format ([RFC6350]) and to
   be unambiguous, extendable and simple to process.  In contrast with
   jCard, it is not a direct mapping from the vCard data model and
   expands semantics where appropriate.

   The JSContact specification declares two main object types: "Card",
   which represents a single contact "card", and "CardGroup" which
   represents a collection of Card objects.  For the purpose of this
   document, only Card objects are considered.  To avoid confusion, in
   the following of this document, the term "JSCard" is used to refer to
   "JSContact Card".

   JSCard differs from jCard in that it:

   *  follows an object-oriented rather than array-oriented approach;

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   *  is simple to process;

   *  requires no extra work in serialization/deserialization from/to a
      data model;

   *  includes no "jagged" arrays;

   *  prefers maps rather than arrays to implement collections;

   *  is able to represent redacted contacts (both "name" and"fullName"
      properties are optional).

   [draft-ietf-jmap-jscontact-vcard] provides informational guidance on
   the conversion of jCard objects into JSCard objects, and vice versa.

3.  Using JSCard objects in RDAP Responses

   Entity objects in RDAP responses MAY include a "jscard" property
   whose value is a JSCard object instead of the "vCardArray" property
   defined in [RFC9083].

   Servers returning the "jscard" property in their response MUST
   include "jscard" in the "rdapConformance" array.

   The JSCard "uid" property SHOULD contain the same value as the RDAP
   "handle" property.

   Since most of the JSCard collections are represented as maps, map
   keys must be defined.  To aid interoperability, RDAP providers are
   RECOMMENDED to use as map keys the following string values and labels
   defined in [RFC5733]:

   *  "org" in the "organizations" map for either the only or the
      internationalized organization;

   *  "addr" in the "addresses" map for either the only or the
      internationalized postal address ;

   *  "email" in the "emails" map for the email address;

   *  "voice" in the "phones" map for the voice number;

   *  "fax" in the "phones" map for the fax number.

   If present, the localized versions of name, organization and postal
   address MUST be inserted into the "localizations" map.

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   Implementers MAY use different mapping schemes to define keys for
   additional entries of the aforementioned maps or others.

   An example of an RDAP response containing a "jscard" property is
   shown in Figure 1.  The "jscard" object in this example has been
   converted from the example included in section 5.1 of [RFC9083].

   {
      "rdapConformance": [
         "rdap_level_0",
         "jscard"
      ],
      "objectClassName" : "entity",
      "handle":"XXXX",
      "jscard":{
        "@type": "Card",
        "uid": "XXXX",
        "fullName": "Joe User" ,
        "name": [
          {"@type": "NameComponent", "type": "surname", "value": "User"},
          {"@type": "NameComponent", "type": "personal", "value": "Joe"},
          {"@type": "NameComponent", "type": "suffix", "value": "ing. jr"},
          {"@type": "NameComponent", "type": "suffix", "value": "M.Sc."}
        ],
        "kind": "individual",
        "preferredContactLanguages": {
          "fr": { "@type": "ContactLanguage", "pref": 1 },
          "en": { "@type": "ContactLanguage", "pref": 2 }
        },
        "organizations": {
          "org": {
            "@type": "Organization",
            "name": "Example"
          }
        },
        "titles": {
          "title": {
            "@type": "Title",
            "title": "Research Scientist"
          },
          "role": {
            "@type": "Title",
            "title": "Project Lead"
          }
        },
        "addresses": {
          "addr": {
            "@type": "Address",

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            "contexts": { "work": true },
            "street": [
                       {"@type": "StreetComponent", "type": "name", "value": "4321 Rue Somewhere"},
                       {"@type": "StreetComponent", "type": "extension", "value": "Suite 1234"}
                      ],
            "locality": "Quebec",
            "region": "QC",
            "postcode": "G1V 2M2",
            "country": "Canada",
            "coordinates": "geo:46.772673,-71.282945",
            "timeZone": "Etc/GMT+5"
          },
          "home": {
            "@type": "Address",
            "contexts": { "private": true },
            "fullAddress": "123 Maple Ave\nSuite 90001\nVancouver\nBC\n1239\n"
          }
        },
        "phones": {
          "voice" : {
            "@type": "Phone",
            "contexts": { "work": true },
            "features": {
               "voice": true,
               "cell": true,
               "video": true,
               "text": true
            },
            "pref": 1,
            "phone": "tel:+1-555-555-1234;ext=102"
          }
        },
        "emails": {
          "email": {
            "@type": "EmailAddress",
            "contexts": { "work": true },
            "email": "joe.user@example.com"
          }
        },
        "online": {
          "key": {
            "@type" : "Resource",
            "contexts": { "work": true },
            "type": "uri",
            "label": "key",
            "resource": "http://www.example.com/joe.user/joe.asc"
          },
          "url": {

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            "@type" : "Resource",
            "contexts": { "private": true },
            "type": "uri",
            "label": "url",
            "resource": "http://example.org"
          }
        }
      },
      "roles":[ "registrar" ],
      "publicIds":[
        {
          "type":"IANA Registrar ID",
          "identifier":"1"
        }
      ],
      "remarks":[
        {
          "description":[
            "She sells sea shells down by the sea shore.",
            "Originally written by Terry Sullivan."
          ]
        }
      ],
      "links":[
        {
          "value":"http://example.com/entity/XXXX",
          "rel":"self",
          "href":"http://example.com/entity/XXXX",
          "type" : "application/rdap+json"
        }
      ],
      "events":[
        {
          "eventAction":"registration",
          "eventDate":"1990-12-31T23:59:59Z"
        }
      ],
      "asEventActor":[
        {
          "eventAction":"last changed",
          "eventDate":"1991-12-31T23:59:59Z"
        }
      ]
   }

            Figure 1: Example of "jscard" in RDAP response

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3.1.  RDAP Query Parameters

   Two new query parameters are defined for the purpose of this
   document.

   The query parameters are OPTIONAL extensions of path segments defined
   in [RFC9082].  They are as follows:

   *  "jscard": a boolean value that allows a client to request the
      "jscard" property in the RDAP response;

   *  "jcard": a boolean value that allows a client to request the
      "vcardArray" property in the RDAP response.

   These parameters are furtherly explained in Section 4.

4.  Transition Considerations

4.1.  RDAP Features Supporting a Transition Process

4.1.1.  Notices and Link Relationships

   RDAP allows servers to communicate service information to clients
   through notices.  An RDAP response may contain one or more notice
   objects ([RFC9083], Section 4.3), each of which may include a set of
   link objects, which can be used to provide clients with references
   and documentation.  These link objects may have a "rel" property
   which defines the relationship type, as described in [RFC8288],
   Section 4.  The transition process outlined in this document uses two
   types of link relation:

   *  "deprecation", as described in
      [draft-ietf-httpapi-deprecation-header];

   *  "alternate", as described in [RFC8288].

4.1.2.  rdapConformance Property

   The information about the specifications used in the construction of
   the response is also described by the strings which appear in the
   "rdapConformance" property of the RDAP response.

4.1.3.  Query Parameters

   Clients are able to ask servers to use specific RDAP features by
   using appropriate query parameters as described in [RFC9082].

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4.2.  Transition Procedure

   The procedure for jCard to JSCard transition consists of four
   contiguous stages.  During the procedure, the presence of "jscard"
   tag in the rdapConformance array indicates that JSCard is returned
   instead of jCard.  The time format used to notify clients about this
   procedure is defined in [RFC3339].

   Some elements of the following procedure are based on the best
   practices in [API-DEPRECATION].

4.2.1.  Transition Stages

4.2.1.1.  Stage 1: only jCard provided

   This stage corresponds to providing jCard as default contact card
   ([RFC9083]).  The RDAP server is not able to provide an alternate
   contact card.  The rdapConformance array MUST NOT contain the
   "jscard" tag.

4.2.1.2.  Stage 2: jCard sunset

   During this stage, the server uses jCard by default, but the RDAP
   server will return JSCard if the client sets the query parameter
   "jscard" to a true value.  The rdapConformance array MUST contain the
   "jscard" tag if JSCard is requested.

   The RDAP server SHOULD include a notice titled "jCard sunset end".
   Such a notice should include a description reporting the jCard sunset
   end time and two links:

   *  "deprecation": a link to a URI-identified resource documenting the
      jCard deprecation;

   *  "alternate": if JSCard is not requested, a link to the JSCard
      version of same resource as identified by the current query string
      plus the parameter "jscard" set to a true value (Figure 2);
      otherwise, only the "deprecation" link is provided (Figure 3).

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   "notices": [
     {
       "title": "jCard sunset end",
       "description": ["2020-07-01T00:00:00Z"],
       "links": [{
           "value": "http://example.net/entity/XXXX",
           "rel": "deprecation",
           "type": "text/html",
           "href": "http://www.example.com/jcard_deprecation.html"
         },
         {
           "value": "http://example.net/entity/XXXX",
           "rel": "alternate",
           "type": "application/rdap+json",
           "href": " http://example.net/entity/XXXX?jscard=1"
         }
       ]
     }
   ]

               Figure 2: jCard sunset - JSCard not requested

   "notices": [
     {
       "title": "jCard sunset end",
       "description": ["2020-07-01T00:00:00Z"],
       "links": [
         {
           "value": "http://example.net/entity/XXXX?jscard=1",
           "rel": "deprecation",
           "type": "text/html",
           "href": "http://www.example.com/jcard_deprecation.html"
         }
       ]
     }
   ]

                 Figure 3: jCard sunset - JSCard requested

4.2.1.3.  Stage 3: jCard deprecation

   This stage corresponds to the provisioning of JSCard by default, but
   the RDAP will return jCard if the client sets the query parameter
   "jcard" to a true value.  The rdapConformance array contains the
   "jscard" tag unless jCard is requested.  The "jscard" query parameter
   is ignored.

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   The RDAP server SHOULD to return a notice titled "jCard deprecation
   end".  Such a notice should include a description reporting the jCard
   deprecation end time and two links:

   *  "deprecation": a link to a URI-identified resource documenting the
      jCard deprecation;

   *  "alternate": if jCard is not requested, a link to the jCard
      version of the same resource as identified by the current query
      string plus the parameter "jcard" set to 1/true/yes (Figure 4);
      otherwise, a link to the JSCard version of the same resource as
      identified by the current query string without the parameter
      "jcard" (Figure 5).

   "notices": [
     {
       "title": "jCard deprecation end",
       "description": ["2020-12-31T23:59:59Z"],
       "links": [
         {
           "value": "http://example.net/entity/XXXX",
           "rel": "deprecation",
           "type": "text/html",
           "href": "http://www.example.com/jcard_deprecation.html"
         },
         {
           "value": "http://example.net/entity/XXXX",
           "rel": "alternate",
           "type": "application/rdap+json",
           "href": " http://example.net/entity/XXXX?jcard=1"
         }
       ]
     }
   ]

             Figure 4: jCard deprecation - jCard not requested

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   "notices": [
     {
       "title": "jCard deprecation end",
       "description": ["2020-12-31T23:59:59Z"],
       "links": [
         {
           "value": "http://example.net/entity/XXXX?jcard=1",
           "rel": "deprecation",
           "type": "text/html",
           "href": "http://www.example.com/jcard_deprecation.html"
         },
         {
           "value": "http://example.net/entity/XXXX?jcard=1",
           "rel": "alternate",
           "type": "application/rdap+json",
           "href": " http://example.net/entity/XXXX"
         }
       ]
     }
   ]

               Figure 5: jCard deprecation - jCard requested

4.2.1.4.  Stage 4: jCard deprecated

   This stage corresponds to providing JSCard as default contact card.
   The RDAP server is not able to provide an alternate contact card.
   The rdapConformance array always contains "jscard" tag.  The RDAP
   server doesn't include any notice about the jCard deprecation
   process.  Both "jscard" and "jcard" query parameters are ignored.

4.2.1.5.  Length

   The length of both jCard sunset and jCard deprecation periods are not
   fixed by this specification.  Best practices in REST API deprecation
   suggest that, depending on the deprecated API's reach, user base and
   service offering, a convenient time could be anywhere between 3 - 8
   months.  Anyway, RDAP providers are recommended to monitor the server
   log to figure out whether declared times need to be changed to meet
   client requirements.

4.2.1.6.  Goals

   The procedure described in this document achieves the following
   goals:

   *  only one contact representation would be included in the response;

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   *  the response would always be compliant to [RFC9083];

   *  clients would be informed about the transition timeline;

   *  the backward compatibility would be guaranteed throughout the
      transition;

   *  servers and clients could execute their transitions independently.

5.  Implementation Status

   NOTE: Please remove this section and the reference to RFC 7942 prior
   to publication as an RFC.

   This section records the status of known implementations of the
   protocol defined by this specification at the time of posting of this
   Internet-Draft, and is based on a proposal described in RFC 7942
   [RFC7942].  The description of implementations in this section is
   intended to assist the IETF in its decision processes in progressing
   drafts to RFCs.  Please note that the listing of any individual
   implementation here does not imply endorsement by the IETF.
   Furthermore, no effort has been spent to verify the information
   presented here that was supplied by IETF contributors.  This is not
   intended as, and must not be construed to be, a catalog of available
   implementations or their features.  Readers are advised to note that
   other implementations may exist.

   According to RFC 7942, "this will allow reviewers and working groups
   to assign due consideration to documents that have the benefit of
   running code, which may serve as evidence of valuable experimentation
   and feedback that have made the implemented protocols more mature.
   It is up to the individual working groups to use this information as
   they see fit".

5.1.  IIT-CNR/Registro.it

   *  Responsible Organization: Institute of Informatics and Telematics
      of National Research Council (IIT-CNR)/Registro.it

   *  Location: https://rdap.pubtest.nic.it/

   *  Description: This implementation includes support for RDAP queries
      using data from the public test environment of .it ccTLD.

   *  Level of Maturity: This is a "proof of concept" research
      implementation.

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   *  Coverage: This implementation includes all of the features
      described in this specification.

   *  Contact Information: Mario Loffredo, mario.loffredo@iit.cnr.it

6.  IANA Considerations

   IANA is requested to register the following values in the RDAP
   Extensions Registry:

   *  Extension identifier: jscard

   *  Registry operator: Any

   *  Published specification: This document.

   *  Contact: IETF <iesg@ietf.org>

   *  Intended usage: This extension represents a contact card provided
      in an RDAP response according to the JSContact specification
      ([draft-ietf-jmap-jscontact]).

7.  Security Considerations

   Unlike jCard, the formatted name as well as any other personally
   identifiable information is not required in JSCard.  The only
   mandatory property, namely "uid", is usually an opaque string.
   Therefore, redacted properties can be merely excluded without using
   placeholder values.

8.  References

8.1.  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>.

   [RFC3339]  Klyne, G. and C. Newman, "Date and Time on the Internet:
              Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
              <https://www.rfc-editor.org/info/rfc3339>.

   [RFC5733]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
              Contact Mapping", STD 69, RFC 5733, DOI 10.17487/RFC5733,
              August 2009, <https://www.rfc-editor.org/info/rfc5733>.

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   [RFC6350]  Perreault, S., "vCard Format Specification", RFC 6350,
              DOI 10.17487/RFC6350, August 2011,
              <https://www.rfc-editor.org/info/rfc6350>.

   [RFC7095]  Kewisch, P., "jCard: The JSON Format for vCard", RFC 7095,
              DOI 10.17487/RFC7095, January 2014,
              <https://www.rfc-editor.org/info/rfc7095>.

   [RFC7942]  Sheffer, Y. and A. Farrel, "Improving Awareness of Running
              Code: The Implementation Status Section", BCP 205,
              RFC 7942, DOI 10.17487/RFC7942, July 2016,
              <https://www.rfc-editor.org/info/rfc7942>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8288]  Nottingham, M., "Web Linking", RFC 8288,
              DOI 10.17487/RFC8288, October 2017,
              <https://www.rfc-editor.org/info/rfc8288>.

   [RFC9082]  Hollenbeck, S. and A. Newton, "Registration Data Access
              Protocol (RDAP) Query Format", STD 95, RFC 9082,
              DOI 10.17487/RFC9082, June 2021,
              <https://www.rfc-editor.org/info/rfc9082>.

   [RFC9083]  Hollenbeck, S. and A. Newton, "JSON Responses for the
              Registration Data Access Protocol (RDAP)", STD 95,
              RFC 9083, DOI 10.17487/RFC9083, June 2021,
              <https://www.rfc-editor.org/info/rfc9083>.

8.2.  Informative References

   [API-DEPRECATION]
              Sandoval, K., "How to Smartly Sunset and Deprecate APIs",
              August 2019, <https://web.archive.org/web/20200417084255/
              https://nordicapis.com/how-to-smartly-sunset-and-
              deprecate-apis/>.

   [draft-ietf-httpapi-deprecation-header]
              Dalal, S. and E. Wilde, "The Deprecation HTTP Header
              Field", <https://datatracker.ietf.org/doc/draft-ietf-
              httpapi-deprecation-header/>.

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   [draft-ietf-jmap-jscontact]
              Stepanek, R. and M. Loffredo, "JSContact: A JSON
              representation of contact data",
              <https://datatracker.ietf.org/doc/draft-ietf-jmap-
              jscontact/>.

   [draft-ietf-jmap-jscontact-vcard]
              Loffredo, M. and R. Stepanek, "JSContact: Converting from
              and to vCard", <https://datatracker.ietf.org/doc/draft-
              ietf-jmap-jscontact-vcard/>.

   [RDAP-PILOT-WG]
              ICANN RDAP Pilot WG, "RDAP Pilot Report", April 2019,
              <https://www.icann.org/en/system/files/files/rdap-pilot-
              report-25apr19-en.pdf>.

Appendix A.  Change Log

A.1.  Change from 00 to 01

   1.   Changed category from "Best Current Practice" to "Standards
        Track"

   2.   Replaced the example of Figure 1

   3.   Changed the title of the "Migration from JCard to JSCard"
        section to "Transition Considerations"

   4.   Added Section 3.1

   5.   Updated Section 6

   6.   Updated Section 7

   7.   Rearranged the description of stage 1 in Section 4.2.1

   8.   Changed the names of the transition stages 1 and 2

   9.   Corrected Figure 2, Figure 4, Figure 5

   10.  Changed the rdapConformance tag "jscard_level_0" to "jscard"

   11.  Removed the "Best Practices for deprecating a REST API features"
        section, but added a useful reference.

A.2.  Change from 01 to 02

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   1.  Removed the sentence "which cannot be represented using jCard" in
       Section 1.1.

A.3.  Change from 02 to 03

   1.  Updated section "Conventions Used in This Document".

   2.  Updated the contact in "IANA Considerations" section.

   3.  Changed the reference draft-loffredo-jmap-jscontact-vcard to
       draft-ietf-jmap-jscontact-vcard.

   4.  Added reference to RFC8174.

   5.  Other minor edits.

A.4.  Change from 03 to 04

   1.  Updated the reference draft-dalal-deprecation-header to draft-
       ietf-httpapi-deprecation-header.

A.5.  Initial WG version

   1.  Ported from draft-loffredo-regext-rdap-jcard-deprecation-04
       renamed to draft-ietf-regext-rdap-jscontact-00.

A.6.  Change from 00 to 01

   1.  Updated Section 3 and Figure 1.

A.7.  Change from 01 to 02

   1.  Updated Section 2 and Figure 1.

A.8.  Change from 02 to 03

   1.  Replaced references to obsolete RFC7482 and RFC7483 with RFC9082
       and RFC9083.

   2.  Updated Section 3 and Figure 1.

Authors' Addresses

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   Mario Loffredo
   IIT-CNR/Registro.it
   Via Moruzzi,1
   56124 Pisa
   Italy

   Email: mario.loffredo@iit.cnr.it
   URI:   http://www.iit.cnr.it

   Gavin Brown
   CentralNic Group plc
   Saddlers House, 44 Gutter Lane
   London
   EC2V 6BR
   United Kingdom

   Phone: +44 20 33 88 0600
   Email: gavin.brown@centralnic.com
   URI:   https://www.centralnic.com

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