rfc2426.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

Network Working Group                                         F. Dawson
Request for Comments: 2426                Lotus Development Corporation
Category: Standards Track                                      T. Howes
                                                Netscape Communications
                                                         September 1998


                      vCard MIME Directory Profile

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1998).  All Rights Reserved.

Abstract

   This memo defines the profile of the MIME Content-Type [MIME-DIR] for
   directory information for a white-pages person object, based on a
   vCard electronic business card. The profile definition is independent
   of any particular directory service or protocol. The profile is
   defined for representing and exchanging a variety of information
   about an individual (e.g., formatted and structured name and delivery
   addresses, email address, multiple telephone numbers, photograph,
   logo, audio clips, etc.). The directory information used by this
   profile is based on the attributes for the person object defined in
   the X.520 and X.521 directory services recommendations. The profile
   also provides the method for including a [VCARD] representation of a
   white-pages directory entry within the MIME Content-Type defined by
   the [MIME-DIR] document.

   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].











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Table of Contents

   Overview.........................................................3
   1. THE VCARD MIME DIRECTORY PROFILE REGISTRATION.................4
   2. MIME DIRECTORY FEATURES.......................................5
    2.1 PREDEFINED TYPE USAGE ......................................5
     2.1.1 BEGIN and END Type ......................................5
     2.1.2 NAME Type ...............................................5
     2.1.3 PROFILE Type ............................................5
     2.1.4 SOURCE Type .............................................5
    2.2 PREDEFINED TYPE PARAMETER USAGE ............................6
    2.3 PREDEFINED VALUE TYPE USAGE ................................6
    2.4 EXTENSIONS TO THE PREDEFINED VALUE TYPES ...................6
     2.4.1 BINARY ..................................................6
     2.4.2 VCARD ...................................................6
     2.4.3 PHONE-NUMBER ............................................7
     2.4.4 UTC-OFFSET ..............................................7
    2.5 STRUCTURED TYPE VALUES .....................................7
    2.6 LINE DELIMITING AND FOLDING ................................8
   3. VCARD PROFILE FEATURES........................................8
    3.1 IDENTIFICATION TYPES .......................................8
     3.1.1 FN Type Definition ......................................8
     3.1.2 N Type Definition .......................................9
     3.1.3 NICKNAME Type Definition ................................9
     3.1.4 PHOTO Type Definition ..................................10
     3.1.5 BDAY Type Definition ...................................11
    3.2 DELIVERY ADDRESSING TYPES .................................11
     3.2.1 ADR Type Definition ....................................11
     3.2.2 LABEL Type Definition ..................................13
    3.3 TELECOMMUNICATIONS ADDRESSING TYPES .......................13
     3.3.1 TEL Type Definition ....................................14
     3.3.2 EMAIL Type Definition ..................................15
     3.3.3 MAILER Type Definition .................................15
    3.4 GEOGRAPHICAL TYPES ........................................16
     3.4.1 TZ Type Definition .....................................16
     3.4.2 GEO Type Definition ....................................16
    3.5 ORGANIZATIONAL TYPES ......................................17
     3.5.1 TITLE Type Definition ..................................17
     3.5.2 ROLE Type Definition ...................................18
     3.5.3 LOGO Type Definition ...................................18
     3.5.4 AGENT Type Definition ..................................19
     3.5.5 ORG Type Definition ....................................20
    3.6 EXPLANATORY TYPES .........................................20
     3.6.1 CATEGORIES Type Definition .............................20
     3.6.2 NOTE Type Definition ...................................21
     3.6.3 PRODID Type Definition .................................21
     3.6.4 REV Type Definition ....................................22
     3.6.5 SORT-STRING Type Definition ............................22



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     3.6.6 SOUND Type Definition ..................................23
     3.6.7 UID Type Definition ....................................24
     3.6.8 URL Type Definition ....................................25
     3.6.9 VERSION Type Definition ................................25
    3.7 SECURITY TYPES ............................................25
     3.7.1 CLASS Type Definition ..................................26
     3.7.2 KEY Type Definition ....................................26
    3.8 EXTENDED TYPES ............................................27
   4. FORMAL GRAMMAR...............................................27
   5. DIFFERENCES FROM VCARD V2.1..................................37
   6. ACKNOWLEDGEMENTS.............................................39
   7. AUTHORS' ADDRESSES...........................................39
   8. SECURITY CONSIDERATIONS......................................39
   9. REFERENCES...................................................40
   10. FULL COPYRIGHT STATEMENT....................................42

Overview

   The [MIME-DIR] document defines a MIME Content-Type for holding
   different kinds of directory information. The directory information
   can be based on any of a number of directory schemas. This document
   defines a [MIME-DIR] usage profile for conveying directory
   information based on one such schema; that of the white-pages type of
   person object.

   The schema is based on the attributes for the person object defined
   in the X.520 and X.521 directory services recommendations. The schema
   has augmented the basic attributes defined in the X.500 series
   recommendation in order to provide for an electronic representation
   of the information commonly found on a paper business card. This
   schema was first defined in the [VCARD] document. Hence, this [MIME-
   DIR] profile is referred to as the vCard MIME Directory Profile.

   A directory entry based on this usage profile can include traditional
   directory, white-pages information such as the distinguished name
   used to uniquely identify the entry, a formatted representation of
   the name used for user-interface or presentation purposes, both the
   structured and presentation form of the delivery address, various
   telephone numbers and organizational information associated with the
   entry. In addition, traditional paper business card information such
   as an image of an organizational logo or identify photograph can be
   included in this person object.

   The vCard MIME Directory Profile also provides support for
   representing other important information about the person associated
   with the directory entry. For instance, the date of birth of the
   person; an audio clip describing the pronunciation of the name
   associated with the directory entry, or some other application of the



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   digital sound; longitude and latitude geo-positioning information
   related to the person associated with the directory entry; date and
   time that the directory information was last updated; annotations
   often written on a business card; Uniform Resource Locators (URL) for
   a website; public key information. The profile also provides support
   for non-standard extensions to the schema. This provides the
   flexibility for implementations to augment the current capabilities
   of the profile in a standardized way. More information about this
   electronic business card format can be found in [VCARD].

1.  The vCard Mime Directory Profile Registration

   This profile is identified by the following [MIME-DIR] registration
   template information. Subsequent sections define the profile
   definition.

   To: [e-mail]

   Subject: Registration of text/directory MIME profile VCARD

   Profile name: VCARD

   Profile purpose: To hold person object or white-pages type of
   directory information. The person schema captured in the directory
   entries is that commonly found in an electronic business card.

   Predefined MIME Directory value specifications used: uri, date,
   date-time, float

   New value specifications: This profile places further constraints on
   the [MIME-DIR] text value specification. In addition, it adds a
   binary, phone-number, utc-offset and vcard value specifications.

   Predefined MIME Directory types used: SOURCE, NAME, PROFILE, BEGIN,
   END.

   Predefined MIME Directory parameters used: ENCODING, VALUE, CHARSET,
   LANGUAGE, CONTEXT.

   New types: FN, N, NICKNAME, PHOTO, BDAY, ADR, LABEL, TEL, EMAIL,
   MAILER, TZ, GEO, TITLE, ROLE, LOGO, AGENT, ORG, CATEGORIES, NOTE,
   PRODID, REV, SORT-STRING, SOUND, URL, UID, VERSION, CLASS, KEY

   New parameters: TYPE

   Profile special notes: The vCard object MUST contain the FN, N and
   VERSION types. The type-grouping feature of [MIME-DIR] is supported
   by this profile to group related vCard properties about a directory



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   entry. For example, vCard properties describing WORK or HOME related
   characteristics can be grouped with a unique group label.

   The profile permits the use of non-standard types (i.e., those
   identified with the prefix string "X-") as a flexible method for
   implementations to extend the functionality currently defined within
   this profile.

2.  MIME Directory Features

   The vCard MIME Directory Profile makes use of many of the features
   defined by [MIME-DIR]. The following sections either clarify or
   extend the content-type definition of [MIME-DIR].

2.1 Predefined Type Usage

   The vCard MIME Directory Profile uses the following predefined types
   from [MIME-DIR].

2.1.1 BEGIN and END Type

   The content entity MUST begin with the BEGIN type with a value of
   "VCARD". The content entity MUST end with the END type with a value
   of "VCARD".

2.1.2 NAME Type

   If the NAME type is present, then its value is the displayable,
   presentation text associated with the source for the vCard, as
   specified in the SOURCE type.

2.1.3 PROFILE Type

   If the PROFILE type is present, then its value MUST be "VCARD".

2.1.4 SOURCE Type

   If the SOURCE type is present, then its value provides information
   how to find the source for the vCard.












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2.2 Predefined Type Parameter Usage

   The vCard MIME Directory Profile uses the following predefined type
   parameters as defined by [MIME-DIR].

        - LANGUAGE

        - ENCODING

        - VALUE

2.3 Predefined VALUE Type Usage

   The predefined data type values specified in [MIME-DIR] MUST NOT be
   repeated in COMMA separated value lists except within the N,
   NICKNAME, ADR and CATEGORIES value types.

   The text value type defined in [MIME-DIR] is further restricted such
   that any SEMI-COLON character (ASCII decimal 59) in the value MUST be
   escaped with the BACKSLASH character (ASCII decimal 92).

2.4 Extensions To The Predefined VALUE Types

   The predefined data type values specified in [MIME-DIR] have been
   extended by the vCard profile to include a number of value types that
   are specific to this profile.

2.4.1 BINARY

   The "binary" value type specifies that the type value is inline,
   encoded binary data. This value type can be specified in the PHOTO,
   LOGO, SOUND, and KEY types.

   If inline encoded binary data is specified, the ENCODING type
   parameter MUST be used to specify the encoding format. The binary
   data MUST be encoded using the "B" encoding format. Long lines of
   encoded binary data SHOULD BE folded to 75 characters using the
   folding method defined in [MIME-DIR].

   The value type is defined by the following notation:

   binary = <A "B" binary encoded string as defined by [RFC 2047].>

2.4.2 VCARD

   The "vcard" value type specifies that the type value is another
   vCard. This value type can be specified in the AGENT type. The value
   type is defined by this specification. Since each of the type



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   declarations with in the vcard value type are being specified within
   a text value themselves, they MUST be terminated with the backslash
   escape sequence "\n" or "\N", instead of the normal newline character
   sequence CRLF. In addition, any COMMA character (ASCII decimal 44),
   SEMI-COLON character (ASCII decimal 59) and COLON character (ASCII
   decimal 58) MUST be escaped with the BACKSLASH character (ASCII
   decimal 92). For example, with the AGENT type a value would be
   specified as:

        AGENT:BEGIN:VCARD\nFN:Joe Friday\nTEL:[phone]\n
         TITLE:Area Administrator\, Assistant\n EMAIL\;TYPE=INTERN\n
         ET:[e-mail]\nEND:VCARD\n

2.4.3 PHONE-NUMBER

   The "phone-number" value type specifies that the type value is a
   telephone number. This value type can be specified in the TEL type.
   The value type is a text value that has the special semantics of a
   telephone number as defined in [CCITT E.163] and [CCITT X.121].

2.4.4 UTC-OFFSET

   The "utc-offset" value type specifies that the type value is a signed
   offset from UTC. This value type can be specified in the TZ type.

   The value type is an offset from Coordinated Universal Time (UTC). It
   is specified as a positive or negative difference in units of hours
   and minutes (e.g., +hh:mm). The time is specified as a 24-hour clock.
   Hour values are from 00 to 23, and minute values are from 00 to 59.
   Hour and minutes are 2-digits with high order zeroes required to
   maintain digit count. The extended format for ISO 8601 UTC offsets
   MUST be used. The extended format makes use of a colon character as a
   separator of the hour and minute text fields.

   The value is defined by the following notation:

        time-hour       = 2DIGIT        ;00-23
        time-minute     = 2DIGIT        ;00-59
        utc-offset      = ("+" / "-") time-hour ":" time-minute

2.5 Structured Type Values

   Compound type values are delimited by a field delimiter, specified by
   the SEMI-COLON character (ASCII decimal 59). A SEMI-COLON in a
   component of a compound property value MUST be escaped with a
   BACKSLASH character (ASCII decimal 92).





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   Lists of values are delimited by a list delimiter, specified by the
   COMMA character (ASCII decimal 44). A COMMA character in a value MUST
   be escaped with a BACKSLASH character (ASCII decimal 92).

   This profile supports the type grouping mechanism defined in [MIME-
   DIR]. Grouping of related types is a useful technique to communicate
   common semantics concerning the properties of a vCard.

2.6 Line Delimiting and Folding

   This profile supports the same line delimiting and folding methods
   defined in [MIME-DIR]. Specifically, when parsing a content line,
   folded lines must first be unfolded according to the unfolding
   procedure described in [MIME-DIR]. After generating a content line,
   lines longer than 75 characters SHOULD be folded according to the
   folding procedure described in [MIME DIR].

   Folding is done after any content encoding of a type value. Unfolding
   is done before any decoding of a type value in a content line.