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vCard Format Extension for JSContact
draft-ietf-calext-vcard-jscontact-extensions-05

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This is an older version of an Internet-Draft whose latest revision state is "Active".
Authors Robert Stepanek , Mario Loffredo
Last updated 2023-04-13 (Latest revision 2023-04-05)
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draft-ietf-calext-vcard-jscontact-extensions-05
Calendaring Extensions                                       R. Stepanek
Internet-Draft                                                  Fastmail
Updates: 6350 (if approved)                                  M. Loffredo
Intended status: Standards Track                                 IIT-CNR
Expires: 7 October 2023                                     5 April 2023

                  vCard Format Extension for JSContact
            draft-ietf-calext-vcard-jscontact-extensions-05

Abstract

   This document defines a set of new properties for vCard and extends
   the use of existing ones.  Their primary purpose is to align the same
   set of features between the JSContact and vCard formats, but the new
   definitions also aim to be useful within just the vCard format.

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 7 October 2023.

Copyright Notice

   Copyright (c) 2023 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 Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Notational Conventions  . . . . . . . . . . . . . . . . .   2
     1.2.  ABNF Notations  . . . . . . . . . . . . . . . . . . . . .   3
   2.  New Properties  . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  CONTACT-CHANNEL-PREF Property . . . . . . . . . . . . . .   3
     2.2.  CREATED Property  . . . . . . . . . . . . . . . . . . . .   4
     2.3.  GRAMMATICAL-GENDER Property . . . . . . . . . . . . . . .   4
     2.4.  LOCALE Property . . . . . . . . . . . . . . . . . . . . .   6
     2.5.  PRONOUNS Property . . . . . . . . . . . . . . . . . . . .   7
     2.6.  SOCIALPROFILE Property  . . . . . . . . . . . . . . . . .   8
   3.  New Parameters  . . . . . . . . . . . . . . . . . . . . . . .   9
     3.1.  AUTHOR Parameter  . . . . . . . . . . . . . . . . . . . .   9
     3.2.  AUTHOR-NAME Parameter . . . . . . . . . . . . . . . . . .   9
     3.3.  CREATED Parameter . . . . . . . . . . . . . . . . . . . .  10
     3.4.  DERIVED Parameter . . . . . . . . . . . . . . . . . . . .  10
     3.5.  RANKS Parameter . . . . . . . . . . . . . . . . . . . . .  11
     3.6.  PROP-ID Parameter . . . . . . . . . . . . . . . . . . . .  12
     3.7.  SERVICE-TYPE Parameter  . . . . . . . . . . . . . . . . .  12
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     6.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

   The JSContact [I-D.ietf-calext-jscontact] format aims to be an
   alternative to the vCard [RFC6350] format for representation of
   contact and address book data.  As such, it introduces new semantics
   that are not covered in the current definition of vCard and its
   various extensions.  Converting contact data between the two formats
   is defined in [I-D.ietf-calext-jscontact-vcard] with the goal of not
   loosing any semantics during conversion.  In order to do so, this
   document defines a new set of properties for vCard and extends
   existing definitions.

1.1.  Notational Conventions

   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.

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1.2.  ABNF Notations

   The ABNF definitions in this document use the notations of [RFC5234].
   ABNF rules not defined in this document either are defined in
   [RFC5234] (such as the ABNF for CRLF, WSP, DQUOTE, VCHAR, ALPHA, and
   DIGIT) or [RFC6350].

2.  New Properties

2.1.  CONTACT-CHANNEL-PREF Property

   Property name:  CONTACT-CHANNEL-PREF

   Purpose:  This property defines which channels the entity associated
      with this vCard prefers to be contacted with.

   Value type:  A single text value, restricted to an enumerated list of
      allowed values.

   Cardinality:  *

   Property parameters:  The PREF parameter defines the preference of
      this contact channel in relation to other contact channels.  The
      TYPE parameter defines when to use this preference.

   Description:  This defines an order of preferences for contact
      channels.  The contact channels supported in this specification
      are phone numbers, email, instant messaging and postal delivery.
      They are identified by the name of the respective vCard property.

   Format definition:  This property is defined by the following
      notation:

      contact-channel-pref  = "CONTACT-CHANNEL-PREF"
                          *(";" contact-channel-pref-param )
                            ":" contact-channel-pref-value

      contact-channel-pref-param  = type-param / pref-param / any-param

      contact-channel-pref-value = "ADR" / "EMAIL" / "IMPP" / "TEL" /
                                   x-value

   Example(s):
      CONTACT-CHANNEL-PREF;PREF=1:EMAIL
      CONTACT-CHANNEL-PREF;PREF=2:TEL

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2.2.  CREATED Property

   Property name:  CREATED

   Purpose:  This property defines the date and time when the vCard was
      created

   Value type:  A single timestamp value.

   Cardinality:  *1

   Property parameters:  VALUE

   Description:  This is the time stamp when the vCard was created.
      Copying the vCard across systems does not count as a new creation,
      nor does a new revision.  Instead, the time stamp value typically
      stays unchanged for the existence of the vCard.

   Format definition:  This property is defined by the following
      notation:

      created       = "CREATED" createdparam ":" timestamp

      createdparam  = *(
                       ;
                       ; The following is OPTIONAL,
                       ; but MUST NOT occur more than once.
                       ;
                       (";" "VALUE" "=" "TIMESTAMP") /
                       ;
                       ; The following is OPTIONAL,
                       ; and MAY occur more than once.
                       ;
                       (";" any-param)
                       ;
                       )

   Example(s):
      CREATED:20220705093412Z
      CREATED;VALUE=TIMESTAMP:20211022T140000-05

2.3.  GRAMMATICAL-GENDER Property

   Property name:  GRAMMATICAL-GENDER

   Purpose:  This property defines the grammatical gender that shall be
      used to address the entity represented by this vCard.

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   Value type:  A single text value, restricted to an enumerated list of
      allowed values.

   Cardinality:  *

   Property parameters:  LANG

   Description:  This property defines the grammatical gender that the
      contact prefers to be addressed by or referred at.  Multiple
      occurrences of this property are allowed, but SHOULD be
      distinguished by the LANG parameter.

      Many human languages use grammatical genders in salutations and
      other language constructs.  For example, the German language
      typically distinguishes between the grammatical gender of the
      recipient in salutations.  The allowed values for this property
      aim to cover grammatical genders for the majority of human
      languages.  This specification registers an initial list (Table 3)
      of allowed values at the IANA vCard Property Values Registry, but
      this may be extended later.

   Format definition:  This property is defined by the following
      notation:

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      gram-gender       = "GRAMMATICAL-GENDER" gram-gender-param
                            ":" gram-gender-value

      gram-gender-param =
                      *(
                       ;
                       ; The following is OPTIONAL,
                       ; but MUST NOT occur more than once.
                       ;
                       (";" language-param) /
                       ;
                       ; The following is OPTIONAL,
                       ; and MAY occur more than once.
                       ;
                       (";" any-param)
                       ;
                       )

      gram-gender-value = "animate" /
                          "common" /
                          "feminine" /
                          "inanimate" /
                          "masculine" /
                          "neuter" /
                          iana-token
                          x-value

   Example(s):
      GRAMMATICAL-GENDER:neuter

2.4.  LOCALE Property

   Property name:  LOCALE

   Purpose:  This property defines the default locale that human-
      readable text values in this vCard should be assumed written in.

   Value type:  A single Language-Tag value as defined in Section 4 of
      [RFC6350].

   Cardinality:  *1

   Property parameters:  The LANG parameter MUST NOT be assigned to this
      property.

   Description:  This property defines the locale in which property

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      values of type TEXT shall be assumed to be written for this vCard.
      If a vCard property includes the LANG parameter, then the
      parameter value has higher precedence than the LOCALE property
      value.

   Format definition:  This property is defined by the following
      notation:

      locale       = "LOCALE" any-param ":" Language-Tag
                     ; Language-Tag is defined in RFC6350, Section 4.

   Example(s):
      LOCALE:de-AT

2.5.  PRONOUNS Property

   Property name:  PRONOUNS

   Purpose:  This property defines the pronouns that shall be used to
      refer to the entity represented by this vCard.

   Value type:  A single text value.

   Cardinality:  *

   Property parameters:  LANG, PREF, TYPE

   Description:  This property contains the pronouns that the contact
      chooses to use for themselves.  The value is free-form text.
      These pronouns shall be used when addressing or referring to the
      contact.  Multiple occurrences of this property MAY define
      pronouns for multiple languages, preferences and contexts.

   Format definition:  This property is defined by the following
      notation:

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      pronouns       = "PRONOUNS" pronouns-param ":" text

      pronouns-param =
                      *(
                       ;
                       ; The following is OPTIONAL,
                       ; but MUST NOT occur more than once.
                       ;
                       (";" language-param / pref-param / type-param) /
                       ;
                       ; The following is OPTIONAL,
                       ; and MAY occur more than once.
                       ;
                       (";" any-param)
                       ;
                       )

   Example(s):
      PRONOUNS;LANG=en:they/them

2.6.  SOCIALPROFILE Property

   Property name:  SOCIALPROFILE

   Purpose:  To specify the URI or username for social media profiles
      associated with the object the vCard represents.

   Value type:  A single URI or TEXT value.  The default value type is
      URI.

   Cardinality:  *

   Property parameters:  The SERVICE-TYPE parameter SHOULD be assigned
      to this property if the value type is URI.  It MUST be assigned if
      the value type is TEXT.  In either case, it MUST NOT be assigned
      more than once.

   Description:  Several vCard address book implementations currently
      use an experimental X-SOCIALPROFILE property to store social media
      profiles for contacts.  This specification provides an IANA-
      registered property for the same purpose.  In addition to the
      typical use of this property with URI values, it also allows to
      set usernames for social media services as free-text TEXT values,
      in which case the service name MUST be provided as a parameter.

   Format definition:  This property is defined by the following
      notation:

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      socialpr       = "SOCIALPROFILE" socialpr-param ":"
                                       socialpr-value

      socialpr-param = "VALUE=uri" / "VALUE=text" /
                       service-type-param / any-param

      socialpr-value = URI / text

   Example(s):
      SOCIALPROFILE;SERVICE-TYPE=Twitter:https://twitter.com/ietf
      SOCIALPROFILE:https://github.com/github
      SOCIALPROFILE;SERVICE-TYPE=SomeSite;VALUE=TEXT:peter94

3.  New Parameters

3.1.  AUTHOR Parameter

   Parameter name:  AUTHOR

   Purpose:  This parameter identifies the author of the associated
      property value.

   Description:  This parameter MAY be set on any property where
      conveying authorship is desired.  It identifies the author as a
      URI [RFC3986].  Since every valid URI includes the COLON (U+003A)
      character, the parameter value MUST be quoted.  Note that as an
      alternative or in addition to this parameter, the AUTHOR-NAME
      parameter allows to name an author as free-text value (see
      Section 3.2).

   Format definition:
      author-param    = "AUTHOR" "=" DQUOTE 1*QSAFE-CHAR DQUOTE
                      ; a valid URI from Section 3 of [RFC3986]

   Example(s):
      NOTE;AUTHOR="mailto:john@example.com":This is some note.

3.2.  AUTHOR-NAME Parameter

   Parameter name:  AUTHOR-NAME

   Purpose:  This parameter names the author of the associated property
      value.

   Description:  This parameter MAY be set on any property where
      conveying authorship is desired.  It names the author as a free-
      text value.  The parameter value MUST NOT be empty.
      Implementations MUST take care to quote the name part, if

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      otherwise the part would not be a valid param-value (see
      Section 3.3 of [RFC6350]).  Note that as an alternative or in
      addition to this parameter, the AUTHOR parameter allows to
      identify an author by URI (see Section 3.1).

   Format definition:
      author-name-param    = "AUTHOR-NAME" "=" param-value ; not empty

   Example(s):
      NOTE;AUTHOR-NAME=John Doe:This is some note.
      NOTE;AUTHOR-NAME="_:l33tHckr:_":A note by an unusual author name.

3.3.  CREATED Parameter

   Parameter name:  CREATED

   Purpose:  This parameter defines the date and time when a property
      was created in a vCard.

   Description:  This parameter MAY be set on any property to define the
      point in time when the property was created.  The value MUST be a
      valid TIMESTAMP value as defined in Section 4.3.5 of [RFC6350].
      Generally, updating a property value SHOULD NOT change the
      creation timestamp.  It is up to implementations to decide if a
      property change resembles an update or rather a delete and create.

   Format definition:
      created-param = "CREATED" "=" param-value ;
                   ; a valid TIMESTAMP of Section 4.3.5 of [RFC6350]

   Example(s):
      NOTE;CREATED=20221122T151823Z:This is some note.

3.4.  DERIVED Parameter

   Parameter name:  DERIVED

   Purpose:  This parameter specifies that the value of the associated
      property is derived from some other property value or values.

   Description:  This property parameter MAY be specified on any
      property when the value is derived from some other property or
      properties.  When present with a value of true, clients MUST NOT
      update the property.

      For an example, an implementation may derive the value of the FN
      property from the name components of the N property.  It indicates
      this by setting the DERIVED parameter on the FN property to true.

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   Format definition:
      derived-param    = "DERIVED" "=" ("true" / "false")
      ; Default is false

   Example(s):
      N:;John;Quinlan;Mr.;
      FN;DERIVED=TRUE:Mr.  John Quinlan

3.5.  RANKS Parameter

   Parameter name:  RANKS

   Purpose:  This parameter specifies a ranking among the name
      components of a vCard N property value.

   Description:  The RANKS parameter on a N property assigns a rank
      among the same-typed name components of a N property value.  Some
      cultures assign ranks to name components, such as a _first_ and a
      _second_ surname, or people might prefer to go by their second
      given name.  But the N property value does not allow to infer a
      culturally or otherwise significant rank from the order in which
      same-typed name components are stored in it.

      The parameter value is structurally equivalent to the multi-valued
      N property value: ranks of different name component types are
      separated by semi-colon, ranks among the same name component types
      are separated by comma.  The rank is an integer number larger than
      or equal to 1 and indicates the first or nth rank.  Its location
      within the RANKS parameter value ranks the name component value at
      that same position within the N property value.  An empty or
      absent rank indicates that the rank of its related name component
      value is undefined.  If the RANKS parameter is set, its value MUST
      NOT be the empty string.

   Format definition:
      NONZERO-DIGIT   = %x31-39 ; "1" to "9"

      ranks-param     = ranks-component 4(";" ranks-component)
      ranks-component = rank *("," rank)
      rank            = (NONZERO-DIGIT *DIGIT) / ""

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   Example(s):
      N;RANKS="2,1":Gómez,Rodriguez;Pablo;;;
                   ; The culturally "first" surname is Rodriguez but it
                   ; appears at the second position in the N property.

      N;RANKS=",1;,1":Hamilton,Cartland;Mary,Barbara;;Dame;
                   ; The writer Dame Mary Barbara Hamilton Cartland
                   ; published as "Barbara Cartland"

3.6.  PROP-ID Parameter

   Parameter name:  PROP-ID

   Purpose:  This parameter identifies a property among all its siblings
      of the same type.

   Description:  This parameter uniquely identifies a property among all
      of its siblings with the same name within a vCard.  A valid PROP-
      ID value must be of 1 and a maximum of 255 octets in size, and it
      MUST only contain the ASCII alphanumeric characters (A-Za-z0-9),
      hyphen (-), and underscore (_).  The identifier only has the
      purpose to uniquely identify siblings, its value has no other
      meaning.  If an application makes use of PROP-ID it SHOULD assign
      a unique identifier to each sibling property of the same name
      within their embedding component.  The same identifier MAY be used
      for properties of a different name, and it MAY also be assigned to
      a same-named property that is not a sibling.

      Resolving duplicate identifier conflicts is specific to the
      application.  Similarly, handling properties where some but not
      all siblings have a PROP-ID is assigned, is application-specific.

   Format definition:
      prop-id-param  = "PROP-ID" "=" 1*255(ALPHA / DIGIT / "-"/ "_")

   Example(s):
      PHOTO;PROP-ID=p827:data:image/jpeg;base64,MIICajCCAdOgAwIBAg
              <...remainder of base64-encoded data...>

3.7.  SERVICE-TYPE Parameter

   Parameter name:  SERVICE-TYPE

   Purpose:  To define the online service name associated with a
      messaging or social media profile.

   Description:  This parameter MAY be specified on a IMPP or

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      SOCIALPROFILE property to name the online service associated with
      that property value.  Its value is case-sensitive, its letter
      cases MUST be preserved.

      Several vCard address book implementations currently use an
      experimental X-SERVICE-TYPE parameter.  This specification
      provides an IANA-registered parameter for the same purpose.

   Format definition:
      service-type-param    = param-value

   Example(s):
      SOCIALPROFILE;SERVICE-TYPE=Twitter:https://twitter.com/ietf

4.  Security Considerations

   This specification extends the vCard Format Specification.  The same
   security considerations as outlined in Section 9 of [RFC6350] apply.

5.  IANA Considerations

   IANA is requested to add the following entries to the "vCard
   Properties" registry, defined in Section 10.3.1. of [RFC6350].

     +===========+======================+============================+
     | Namespace | Property             | Reference                  |
     +===========+======================+============================+
     |           | CONTACT-CHANNEL-PREF | This document, Section 2.1 |
     +-----------+----------------------+----------------------------+
     |           | CREATED              | This document, Section 2.2 |
     +-----------+----------------------+----------------------------+
     |           | GRAMMATICAL-GENDER   | This document, Section 2.3 |
     +-----------+----------------------+----------------------------+
     |           | LOCALE               | This document, Section 2.4 |
     +-----------+----------------------+----------------------------+
     |           | PRONOUNS             | This document, Section 2.5 |
     +-----------+----------------------+----------------------------+
     |           | SOCIALPROFILE        | This document, Section 2.6 |
     +-----------+----------------------+----------------------------+

                       Table 1: New VCARD Properties

   IANA is requested to add the following entries to the "vCard
   Parameters" registry, defined in Section 10.3.2. of [RFC6350].

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         +===========+==============+============================+
         | Namespace | Parameter    | Reference                  |
         +===========+==============+============================+
         |           | AUTHOR       | This document, Section 3.1 |
         +-----------+--------------+----------------------------+
         |           | AUTHOR-NAME  | This document, Section 3.2 |
         +-----------+--------------+----------------------------+
         |           | CREATED      | This document, Section 3.3 |
         +-----------+--------------+----------------------------+
         |           | DERIVED      | This document, Section 3.4 |
         +-----------+--------------+----------------------------+
         |           | PROP-ID      | This document, Section 3.6 |
         +-----------+--------------+----------------------------+
         |           | RANKS        | This document, Section 3.5 |
         +-----------+--------------+----------------------------+
         |           | SERVICE-TYPE | This document, Section 3.7 |
         +-----------+--------------+----------------------------+

                       Table 2: New VCARD Parameters

   IANA is requested to add the following entries to the "vCard Property
   Values" registry, defined in Section 10.3.4. of [RFC6350].

      +====================+===========+============================+
      | Property           | Value     | Reference                  |
      +====================+===========+============================+
      | GRAMMATICAL-GENDER | animate   | This document, Section 2.3 |
      +--------------------+-----------+----------------------------+
      | GRAMMATICAL-GENDER | common    | This document, Section 2.3 |
      +--------------------+-----------+----------------------------+
      | GRAMMATICAL-GENDER | feminine  | This document, Section 2.3 |
      +--------------------+-----------+----------------------------+
      | GRAMMATICAL-GENDER | inanimate | This document, Section 2.3 |
      +--------------------+-----------+----------------------------+
      | GRAMMATICAL-GENDER | masculine | This document, Section 2.3 |
      +--------------------+-----------+----------------------------+
      | GRAMMATICAL-GENDER | neuter    | This document, Section 2.3 |
      +--------------------+-----------+----------------------------+

                     Table 3: New VCARD Property Values

6.  References

6.1.  Normative References

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   [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>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/info/rfc3986>.

   [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234,
              DOI 10.17487/RFC5234, January 2008,
              <https://www.rfc-editor.org/info/rfc5234>.

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

   [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>.

6.2.  Informative References

   [I-D.ietf-calext-jscontact]
              Stepanek, R. and M. Loffredo, "JSContact: A JSON
              representation of contact data", Work in Progress,
              Internet-Draft, draft-ietf-calext-jscontact-08, 13 March
              2023, <https://datatracker.ietf.org/doc/html/draft-ietf-
              calext-jscontact-08>.

   [I-D.ietf-calext-jscontact-vcard]
              Loffredo, M. and R. Stepanek, "JSContact: Converting from
              and to vCard", Work in Progress, Internet-Draft, draft-
              ietf-calext-jscontact-vcard-06, 10 January 2023,
              <https://datatracker.ietf.org/doc/html/draft-ietf-calext-
              jscontact-vcard-06>.

Authors' Addresses

   Robert Stepanek
   Fastmail
   PO Box 234, Collins St West
   Melbourne  VIC 8007
   Australia
   Email: rsto@fastmailteam.com

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Internet-Draft         vCard JSContact Extensions             April 2023

   Mario Loffredo
   IIT-CNR
   Via Moruzzi,1
   56124 Pisa
   Italy
   Email: mario.loffredo@iit.cnr.it

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