iCalendar Transport-Independent Interoperability Protocol (iTIP)
RFC 5546

Network Working Group                                      C. Daboo, Ed.
Request for Comments: 5546                                    Apple Inc.
Obsoletes: 2446                                            December 2009
Updates: 5545
Category: Standards Track

    iCalendar Transport-Independent Interoperability Protocol (iTIP)

Abstract

   This document specifies a protocol that uses the iCalendar object
   specification to provide scheduling interoperability between
   different calendaring systems.  This is done without reference to a
   specific transport protocol so as to allow multiple methods of
   communication between systems.  Subsequent documents will define
   profiles of this protocol that use specific, interoperable methods of
   communication between systems.

   The iCalendar Transport-Independent Interoperability Protocol (iTIP)
   complements the iCalendar object specification by adding semantics
   for group scheduling methods commonly available in current
   calendaring systems.  These scheduling methods permit two or more
   calendaring systems to perform transactions such as publishing,
   scheduling, rescheduling, responding to scheduling requests,
   negotiating changes, or canceling.

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) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   to this document.  Code Components extracted from this document must

Daboo                       Standards Track                     [Page 1]
RFC 5546                          iTIP                     December 2009

   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 BSD License.

   This document may contain material from IETF Documents or IETF
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   than English.

Table of Contents

   1. Introduction and Overview .......................................5
      1.1. Formatting Conventions .....................................5
      1.2. Related Documents ..........................................6
      1.3. Roles ......................................................6
      1.4. Methods ....................................................7
   2. Interoperability Models .........................................9
      2.1. Application Protocol ......................................10
           2.1.1. Scheduling State ...................................10
           2.1.2. Delegation .........................................10
           2.1.3. Acting on Behalf of Other Calendar Users ...........11
           2.1.4. Component Revisions ................................11
           2.1.5. Message Sequencing .................................12
   3. Application Protocol Elements ..................................13
      3.1. Common Component Restriction Tables .......................15
           3.1.1. VCALENDAR ..........................................15
           3.1.2. VTIMEZONE ..........................................15
           3.1.3. VALARM .............................................17
      3.2. Methods for VEVENT Calendar Components ....................17
           3.2.1. PUBLISH ............................................18
           3.2.2. REQUEST ............................................20
           3.2.3. REPLY ..............................................25
           3.2.4. ADD ................................................27
           3.2.5. CANCEL .............................................29