rfc2739.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                                            T. Small
Request for Comments: 2739                                  XpertSite.Com
Category: Standards Track                                     D. Hennessy
                                                                   ISOCOR
                                                                F. Dawson
                                                                    Lotus
                                                             January 2000


                 Calendar Attributes for vCard and LDAP


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 (2000).  All Rights Reserved.

Abstract

   When scheduling a calendar entity, such as an event, it is a
   prerequisite that an organizer has the calendar address of each
   attendee that will be invited to the event. Additionally, access to
   an attendee's current "busy time" provides an a priori indication of
   whether the attendee will be free to participate in the event.

   In order to meet these challenges, a calendar user agent (CUA) needs
   a mechanism to locate (URI) individual user's calendar and free/busy
   time.

   This memo defines three mechanisms for obtaining a URI to a user's
   calendar and free/busy time. These include:

   - Manual transfer of the information;

   - Personal data exchange using the vCard format; and

   - Directory lookup using the LDAP protocol.







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Table of Contents

   1 CALENDARING AND SCHEDULING URIS...................................3
    1.1 FREE/BUSY URI (FBURL) .........................................3
    1.2 CALENDAR ACCESS URI (CAPURI) ..................................4
    1.3 CALENDAR URI (CALURI) .........................................4
    1.4 DEFAULT URIS ..................................................4
   2 DISTRIBUTION......................................................4
    2.1 MANUAL TRANSFER ...............................................5
    2.2 PERSONAL DATA EXCHANGE USING A VCARD ..........................5
    2.3 VCARD SCHEMA EXTENSIONS .......................................5
     2.3.1 FBURL Property IANA Registration ...........................6
     2.3.2 CALADRURI Property IANA Registration .......................7
     2.3.3 CAPURI Property IANA Registration ......................... 8
     2.3.4 CALURI Property IANA Registration ......................... 8
    2.4 DIRECTORY LOOKUP USING THE LDAP V3 PROTOCOL .................. 9
     2.4.1 LDAP Schema Extensions .................................... 9
     2.4.2 Notation ..................................................10
     2.4.3 Object Definitions ........................................10
       2.4.3.1 calEntry ..............................................10
     2.4.4 Attribute Definitions .....................................10
       2.4.4.1 calCalURI .............................................10
       2.4.4.2 calFBURL ..............................................10
       2.4.4.3 calCAPURI .............................................11
       2.4.4.4 calCalAdrURI ..........................................11
       2.4.4.5 calOtherCalURIs .......................................11
       2.4.4.6 calOtherFBURLs ........................................11
       2.4.4.7 calOtherCAPURIs .......................................12
       2.4.4.8 calOtherCalAdrURIs ....................................12
   3 IANA Considerations..............................................12
   4 Security Considerations..........................................12
   5 Acknowledgments..................................................13
   6 Authors' Addresses...............................................13
   7 Bibliography.....................................................15
   8 Full Copyright Statement.........................................16
















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1  Calendaring and Scheduling URIs

   This memo defines four classes of URIs. URIs are more useful if it is
   understood what the URIs point to. Here is a brief description:

1.1 Free/Busy URI (FBURL)

   The free/busy URI is defined to be a transport independent location
   where a client can obtain information about when a user is busy. At
   the present time, this URI only points to busy time data. Future
   revisions of this specification may provide for the extended
   capability of publishing free time data.

   If a calendaring and scheduling client (i.e., CUA) were to retrieve
   data from this location using FTP or HTTP, it would get back an
   iCalendar object [4] containing one or more "VFREEBUSY" calendar
   components. If a MIME transport is being used, the response will be
   contained within a "text/calendar" MIME body part as specified in the
   iCalendar specification [4]. For example:

      BEGIN:VCALENDAR
      VERSION:2.0
      PRODID:-//hacksw/handcal//NONSGML v1.0//EN
      METHOD:PUBLISH
      BEGIN:VFREEBUSY
      ATTENDEE:MAILTO:[e-mail]
      DTSTART:19971013T050000Z
      DTEND:19971124T050000Z
      DTSTAMP:19970901T083000Z
      FREEBUSY:19971015T133000Z/19971015T180000Z
      FREEBUSY:19971015T190000Z/19971015T220000Z
      FBURL:http://www.host.com/calendar/busy/jdoe.ifb
      END:VFREEBUSY
      END:VCALENDAR

   The amount of busy time data pointed to by the FBURL will generally
   be pre-determined; for example one month of busy time data. As a
   guideline, it is recommended that the previous six weeks of busy time
   data be published at the location associated with the FBURL. If this
   URI points to a file resource, it is recommended that the file
   extension be "ifb" to distinguish it from an arbitrary iCalendar
   object (e.g., with the "ics" file extension).









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1.2 Calendar Access URI (CAPURI)

   The Calendar Access URI is defined to be a protocol independent
   location from which a calendaring and scheduling client (i.e., CUA)
   can communicate with a user's entire calendar.

   The semantics for using this URI as an access protocol locator are
   yet to be defined by the IETF CALSCH Working Group. This will be
   addressed in the "Calendar Access Protocol" specification.

1.3 Calendar URI (CALURI)

   The Calendar URI is defined to be a protocol independent location
   from which a calendaring and scheduling client (i.e. CUA) can
   retrieve an entire copy of a user's calendar. Retrieving data from
   this URI obtains a published "snapshot" of the user's calendar.

   HTTP URI -- If the URI is an HTTP URI, then the content returned with
   a GET should be a "text/calendar" MIME body part containing one or
   more iCalendar object.

   FTP URI -- If the URI is an FTP URI, then the resource pointed to
   should be a file with an "ics" file extension containing one or more
   iCalendar objects.

1.4 Default URIs

   There are many cases where a user may have more than one calendar. In
   these cases, a user may have multiple URIs, each URI pointing to a
   calendar or free/busy data.

   To make the case of multiple calendars simpler for clients, the
   concept of the "default" calendar is introduced. A "default" calendar
   is one that the user has designated as the calendar that other users
   should look at when accessing the user's calendar, or retrieving the
   user's free/busy time.

   The default calendar may, in fact, include rolled-up information from
   all the user's other calendars. The other calendars may only exist
   for organizational purposes.

2  Distribution

   These four URIs provide valuable pointers to calendaring and
   scheduling data that other users need in order to know when to
   schedule meetings, etc. There are several possibilities on how users
   can communicate these URIs to other users. The following section
   outlines how these URIs can be distributed to other users.



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2.1 Manual Transfer

   The simplest way to obtain these URIs is for a user to communicate
   the URIs using some out-of-band mechanism such as verbally, or in an
   e-mail message, or by printing these URIs on a paper business card.

   When using this mechanism, the user obtains these URIs using an out-
   of-band mechanism and then enters these URIs into their calendaring
   software manually.

2.2 Personal Data Exchange Using A vCard

   A more sophisticated way to obtain these URIs is for users to publish
   vCards containing these URIs. The vCard object can be transferred
   between one another. Since many e-mail clients allow a user to
   automatically include a vCard with every message that the user sends,
   this provides a simple, transparent way for a user to distribute
   their calendaring and scheduling URIs.

   On the receiving end, an e-mail client that provides an integrated
   vCard database can provide a way to lookup calendaring URIs for users
   whose vCards are stored locally.

2.3 vCard Schema Extensions

   Since the vCard [3] specification doesn't specify how to encode
   calendaring URIs in a vCard, this section is provided as an extension
   to vCard which specifies how to encode calendaring URIs within a
   vCard.

   Inside a vCard object, four new properties are defined: "CALURI",
   "CAPURI", "CALADRURI", and "FBURL", as defined above.

   Any vCard can have one or more of these properties, each representing
   a calendar or free/busy time that is associated with the user.

   One of these properties can be designated as the "default" by adding
   the "PREF" parameter.













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   Here is a simple example of a vCard containing a "FBURL" and a
   "CALURI".

      BEGIN:VCARD
      VERSION:3.0
      N:Dun;Alec
      FN:Alec Dun
      ORG:Microsoft Corporation
      ADR;WORK;POSTAL;PARCEL:;;One Microsoft Way;
       Redmond;WA;98052-6399;USA
      TEL;WORK;MSG:[phone]
      TEL;WORK;FAX:[phone]
      EMAIL;INTERNET:[e-mail]
      CALADRURI;PREF:mailto:[e-mail]
      CALURI;PREF:http://cal.host1.com/user/cal.ics
      FBURL;PREF:http://cal.host1.com/user/fb.ifb
      CALURI:http://cal.company.com/projectA/pjtA.ics
      FBURL:http://cal.company.com/projectA/pjtAfb.ifb
      END:VCARD

2.3.1 FBURL Property IANA Registration

   To: [e-mail]

   Subject: Registration of FBURL type for text/directory MIME type
   vCard profile.

   Type name: FBURL

   Type purpose: To specify the URI for a user's busy time in a vCard
   object.

   Type encoding: 8bit

   Type value: A single URI value.

   Type special notes: Where multiple FBURL properties are specified,
   the default FBURL property is indicated with the PREF parameter. The
   FTP or HTTP type of URI points to an iCalendar object associated with
   a snapshot of the last six weeks of the user's busy time data. If the
   iCalendar object is represented as a file or document, it's file type
   should be "ifb".

   Intended usage: Refer to section 1.1.







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   Type examples:

      FBURL;PREF:http://www.host1.com/busy/janedoe
      FBURL:FTP://ftp.host.com/busy/project-a.ifb

2.3.2  CALADRURI Property IANA Registration

   To: [e-mail]

   Subject: Registration of CALADRURI type for application/directory
   MIME type vCard profile.

   Type name: CALADRURI

   Type purpose: To specify the location to which an event request
   should be sent for the user.

   Type encoding: 8bit

   Type value: A single URI value.

   Type special notes: Where multiple CALADRURI properties are
   specified, the default CALADRURI property is indicated with the PREF
   parameter.

   Intended usage: Refer to section 1.2.

   Type examples:

      CALADRURI;PREF:mailto:[e-mail]





















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2.3.3  CAPURI Property IANA Registration

   To: [e-mail]

   Subject: Registration of CAPURI type for application/directory MIME
   type vCard profile.

   Type name: CAPURI

   Type purpose: To specify a protocol independent location from which a
   calendaring and scheduling client (i.e., CUA) can communicate with a
   user's entire calendar.

   Type encoding: 8bit

   Type value: A single URI value.

   Type special notes: Where multiple CAPURI properties are specified,
   the default CAPURI property is indicated with the PREF parameter.

   Intended usage: Refer to section 1.3.

2.3.4 CALURI Property IANA Registration

   To: [e-mail]

   Subject: Registration of CALURI type for text/directory MIME type
   vCard profile.

   Type name: CALURI

   Type purpose: To specify the URI for a user's calendar in a vCard
   object.

   Type encoding: 8bit

   Type value type: A single URI value.

   Type special notes: Where multiple CALURI properties are specified,
   the default CALURI property is indicated with the PREF parameter. The
   property should contain a URI pointing to an iCalendar object
   associated with a snapshot of the user's calendar store. If the
   iCalendar object is represented as a file or document, it's file type
   should be "ics".

   Intended usage: Refer to section 1.4.





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