Network Working Group C. Daboo
Internet-Draft Apple Inc.
Intended status: Standards Track June 9, 2012
Expires: December 11, 2012
New Properties for iCalendar
draft-daboo-icalendar-extensions-05
Abstract
This document defines a set of new properties for iCalendar data.
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-
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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 December 11, 2012.
Copyright Notice
Copyright (c) 2012 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
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described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 3
3. Backwards Compatible Extension Properties . . . . . . . . . . 3
4. Modifications to Calendar Components . . . . . . . . . . . . . 4
5. Properties . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5.1. NAME Property . . . . . . . . . . . . . . . . . . . . . . 5
5.2. DESCRIPTION Property . . . . . . . . . . . . . . . . . . . 6
5.3. UID Property . . . . . . . . . . . . . . . . . . . . . . . 6
5.4. URL Property . . . . . . . . . . . . . . . . . . . . . . . 7
5.5. TIMEZONE-ID Property . . . . . . . . . . . . . . . . . . . 7
5.6. REFRESH-INTERVAL Property . . . . . . . . . . . . . . . . 8
5.7. VALID Property . . . . . . . . . . . . . . . . . . . . . . 9
5.8. COLOR Property . . . . . . . . . . . . . . . . . . . . . . 10
5.9. IMAGE Property . . . . . . . . . . . . . . . . . . . . . . 11
5.10. BROADCAST Property . . . . . . . . . . . . . . . . . . . . 13
5.11. CONFERENCE Property . . . . . . . . . . . . . . . . . . . 14
6. Property Parameters . . . . . . . . . . . . . . . . . . . . . 16
6.1. ALTURI Property Parameter . . . . . . . . . . . . . . . . 16
6.2. DISPLAY Property Parameter . . . . . . . . . . . . . . . . 17
6.3. FEATURE Property Parameter . . . . . . . . . . . . . . . . 18
6.4. INFO Property Parameter . . . . . . . . . . . . . . . . . 18
6.5. REGION Property Parameter . . . . . . . . . . . . . . . . 19
7. Security Considerations . . . . . . . . . . . . . . . . . . . 19
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19
8.1. Property Registrations . . . . . . . . . . . . . . . . . . 19
8.2. Parameter Registrations . . . . . . . . . . . . . . . . . 20
8.3. Display Types Registry . . . . . . . . . . . . . . . . . . 20
8.4. Feature Types Registry . . . . . . . . . . . . . . . . . . 21
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 21
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 21
10.1. Normative References . . . . . . . . . . . . . . . . . . . 21
10.2. Informative References . . . . . . . . . . . . . . . . . . 21
Appendix A. Change History (To be removed by RFC Editor
before publication) . . . . . . . . . . . . . . . . . 22
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 23
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1. Introduction
The iCalendar [RFC5545] data format is used to represent calendar
data and is used with iTIP [RFC5546] to handle scheduling operations
between calendar users. iCalendar is in widespread use, and in
accordance with provisions in that specification, extension elements
have been added by various vendors to the data format in order to
support and enhance capabilities. This specification collects a
number of these ad-hoc extensions and uses the new IANA registry
capability defined in [RFC5545] to register standard variants with
clearly defined definitions and semantics. In addition, some new
elements are introduced for features that vendors have recently been
requesting.
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
[RFC2119].
The notation used in this memo is the ABNF notation of [RFC5234] as
used by iCalendar [RFC5545]. Any syntax elements shown below that
are not explicitly defined in this specification come from iCalendar
[RFC5545].
3. Backwards Compatible Extension Properties
iCalendar defines properties which can have different value types
indicated by a "VALUE" parameter. The definition of a property
specifies a "default" value type that is assumed to be used when no
"VALUE" parameter is present. However, this poses a problem to
iCalendar parser/generator software that does not know about the
default values for new properties. For example, if a new property
"FOO" were defined with a default value type of URI, and a URI value
with a comma was used, an iCalendar generator not aware of this fact
would likely treat the property value as "TEXT" and apply backslash
escaping to the comma in the value, effectively making it an invalid
URI value.
To avoid this problem, this specification recommends that all
properties not defined in [RFC5545], always include a "VALUE"
parameter, if the type is other than "TEXT". i.e., in the example
above, the "FOO" property would have a "VALUE=URI" parameter. This
allows iCalendar parser/generator software to track the correct types
of unknown properties.
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New properties defined in this specification use the term "no
default" in the "Value Type" definition to indicate that the "VALUE"
parameter has to be included.
4. Modifications to Calendar Components
The following changes to the syntax defined in iCalendar [RFC5545]
are made here. New elements are defined in subsequent sections.
calprops /= *(
;
; The following are OPTIONAL,
; but MUST NOT occur more than once.
;
uid / url / timezid /
refresh / valid / color /
;
; The following are OPTIONAL,
; and MAY occur more than once.
;
name / description / image
;
)
eventprop /= *(
;
; The following are OPTIONAL,
; but MUST NOT occur more than once.
;
color /
;
; The following are OPTIONAL,
; and MAY occur more than once.
;
image / broadcast / conference
;
)
todoprop /= *(
;
; The following are OPTIONAL,
; but MUST NOT occur more than once.
;
color /
;
; The following are OPTIONAL,
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; and MAY occur more than once.
;
image / broadcast / conference
;
)
jourprop /= *(
;
; The following are OPTIONAL,
; but MUST NOT occur more than once.
;
color /
;
; The following are OPTIONAL,
; and MAY occur more than once.
;
image
;
)
5. Properties
5.1. NAME Property
Property Name: NAME
Purpose: This property specifies the name of the calendar.
Value Type: TEXT
Property Parameters: IANA, non-standard, alternate text
representation, and language property parameters can be specified
on this property.
Conformance: This property can be specified multiple times in an
iCalendar object. However, each property MUST represent the name
of the calendar in a different language.
Description: This property is used to specify a name (a short, one-
line description) of the iCalendar object that can be used by
calendar user agents when presenting the calendar data to a user.
Whilst a calendar only has a single name, multiple language
variants can be specified by including this property multiple
times with different "LANGUAGE" parameter values on each.
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Format Definition: This property is defined by the following
notation:
name = "NAME" nameparam ":" text CRLF
nameparam = *(
;
; The following are OPTIONAL,
; but MUST NOT occur more than once.
;
(";" altrepparam) / (";" languageparam) /
;
; The following is OPTIONAL,
; and MAY occur more than once.
;
(";" other-param)
;
)
Example: The following is an example of this property:
NAME:Company Vacation Days
5.2. DESCRIPTION Property
This specification modifies the definition of the "DESCRIPTION"
property to allow it to be defined on an iCalendar object. The
following additions are made to the definition of this property.
Purpose: This property specifies the description of the calendar.
Conformance: This property can be specified multiple times in an
iCalendar object. However, each property MUST represent the
description of the calendar in a different language.
Description: This property is used to specify a lengthy textual
description of the iCalendar object that can be used by calendar
user agents when describing the nature of the calendar data to a
user. Whilst a calendar only has a single description, multiple
language variants can be specified by including this property
multiple times with different "LANGUAGE" parameter values on each.
5.3. UID Property
This specification modifies the definition of the "UID" property to
allow it to be defined on an iCalendar object. The following
additions are made to the definition of this property.
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Purpose: This property specifies the persistent, globally unique
identifier for the iCalendar object.
Conformance: This property can be specified once in an iCalendar
object.
5.4. URL Property
This specification modifies the definition of the "URL" property to
allow it to be defined on an iCalendar object. The following
additions are made to the definition of this property.
Purpose: This property specifies a URL from where the calendar data
was retrieved or where it can be refreshed.
Conformance: This property can be specified once in an iCalendar
object.
Description: This property specifies a URL identifying the source of
the calendar data and a location from where updates can be
retrieved.
5.5. TIMEZONE-ID Property
Property Name: TIMEZONE-ID
Purpose: This property specifies the default time zone identifier
for the iCalendar object as a whole.
Value Type: TEXT
Property Parameters: IANA and non-standard property parameters can
be specified on this property.
Conformance: This property can be specified once in an iCalendar
object.
Description: This property specifies a time zone identifier that
represents the default timezone for which floating time or all-day
events in the iCalendar object can be assumed to be relative to.
It can also be used to choose an initial time zone for use when
creating new components in the iCalendar object. A "VTIMEZONE"
component having a "TZID" property matching the value specified in
this property MUST be present in the iCalendar object.
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Format Definition: This property is defined by the following
notation:
timezid = "TIMEZONE-ID" timezidparam
":" text CRLF
;Same value syntax as "TZID" property.
timezidparam = *(";" other-param)
Example: The following is an example of this property:
TIMEZONE-ID:America/New_York
5.6. REFRESH-INTERVAL Property
Property Name: REFRESH-INTERVAL
Purpose: This property specifies a suggested minimum interval for
polling for changes of the calendar data from the original source
of that data.
Value Type: DURATION - no default
Property Parameters: IANA and non-standard property parameters can
be specified on this property.
Conformance: This property can be specified once in an iCalendar
object.
Description: This property specifies a positive duration that gives
a suggested minimum polling interval for checking for updates to
the calendar data. The value of this property SHOULD be used by
calendar user agents to limit the polling interval for calendar
data updates to the minimum interval specified.
Format Definition: This property is defined by the following
notation:
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refresh = "REFRESH-INTERVAL" refreshparam
":" dur-value CRLF
;consisting of a positive duration of time.
refreshparam = *(
;
; The following is REQUIRED,
; but MUST NOT occur more than once.
;
(";" "VALUE" "=" "DURATION") /
;
; The following is OPTIONAL,
; and MAY occur more than once.
;
(";" other-param)
;
)
Example: The following is an example of this property:
REFRESH-INTERVAL;VALUE=DURATION:P1W
5.7. VALID Property
Property Name: VALID
Purpose: This property specifies when the calendar data is valid.
Value Type: DATE-TIME or PERIOD
Property Parameters: IANA and non-standard property parameters can
be specified on this property.
Conformance: This property can be specified once in an iCalendar
object.
Description: This property specifies a time period for which the
calendar data can assumed to be valid. If a "PERIOD" value type
is used, the validity is assumed to be a time range defined by the
start and end of the period. If a "DATE-TIME" value is used, the
date indicates when end date when the calendar data is no longer
valid. Once the end date has been reached (or at some convenient
time prior) clients SHOULD refresh the calendar data to determine
whether an update is available, extending the range of validity.
The value MUST be specified in UTC.
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Format Definition: This property is defined by the following
notation:
valid = "VALID" validparam ":" validval CRLF
validparam = *(
;
; The following is REQUIRED,
; but MUST NOT occur more than once.
;
(";" "VALUE" "=" ("DATE-TIME" / "PERIOD")) /
;
; The following is OPTIONAL,
; and MAY occur more than once.
;
(";" other-param)
;
)
validval = date-time / period
;Value MUST match value type. Value MUST be in UTC.
Example: The following is an example of this property:
VALID;VALUE=DATE-TIME:20120609T000000Z
VALID;VALUE=PERIOD:20120609T000000Z/P365D
5.8. COLOR Property
Property Name: COLOR
Purpose: This property specifies a color used for displaying the
calendar, event, todo, or journal data.
Value Type: TEXT. The value MUST be three COLON-separated INTEGER
values.
Property Parameters: IANA and non-standard property parameters can
be specified on this property.
Conformance: This property can be specified once in an iCalendar
object, or "VEVENT", "VTODO", or "VJOURNAL" calendar components.
Description: This property specifies a color that client MAY use
when presenting the relevant data to a user. Typically this would
appear as the "background" color of events or tasks. The value
MUST be an RGB value with integer value components in the range
0..255. If a color is specified on a "VEVENT", "VTODO" or
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"VJOURNAL" that SHOULD override any color specified on the
enclosing iCalendar object.
Format Definition: This property is defined by the following
notation:
color = "COLOR" colorparam ":" colorvalue CRLF
colorparam = *(";" other-param)
colorvalue = integer ":" integer ":" integer
; Red, green, and blue values in the range
; 0 - 255.
Example: The following is an example of this property:
COLOR:255:0:255
5.9. IMAGE Property
Property Name: IMAGE
Purpose: This property specifies an image associated with the
calendar or a calendar component.
Value Type: URI or BINARY - no default. The value MUST refer to or
be data with a media type of "image".
Property Parameters: IANA, non-standard, display, inline encoding,
and value data type property parameters can be specified on this
property. The format type parameter can be specified on this
property and is RECOMMENDED for inline binary encoded content
information.
Conformance: This property can be specified multiple times in an
iCalendar object, or "VEVENT", "VTODO", or "VJOURNAL" calendar
components.
Description: This property specifies an image for an iCalendar
object or a calendar component via a uri or directly with inline
data that can be used by calendar user agents when presenting the
calendar data to a user. Multiple properties MAY be used to
specify alternative sets of images with, for example, varying
media subtypes, resolutions or sizes. When multiple properties
are present, calendar user agents SHOULD display only one of them,
picking one that provides the most appropriate image quality, or
display none. The "DISPLAY" parameter is used to indicate the
intended display mode for the image. An "ALTURI" parameter is
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used to provide a "clickable" image where the URI in the parameter
value can be "launched" by a click on the image in the calendar
user agent.
Format Definition: This property is defined by the following
notation:
image = "IMAGE" imageparam ( ":" uri ) /
(
";" "ENCODING" "=" "BASE64"
";" "VALUE" "=" "BINARY"
":" binary
)
CRLF
imageparam = *(
;
; The following is REQUIRED,
; but MUST NOT occur more than once.
;
(";" "VALUE" "=" "URI") /
;
; The following is OPTIONAL for a URI value,
; RECOMMENDED for a BINARY value,
; and MUST NOT occur more than once.
;
(";" fmttypeparam) /
;
; The following are OPTIONAL,
; and MUST NOT occur more than once.
;
(";" alturiparam) / (";" displayparam) /
;
; The following is OPTIONAL,
; and MAY occur more than once.
;
(";" other-param)
;
)
Example: The following is an example of this property:
IMAGE;VALUE=URI;DISPLAY=BACKGROUND;FMTTYPE=image/png:h
ttp://example.com/images/party.png
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5.10. BROADCAST Property
Property Name: BROADCAST
Purpose: This property specifies information for accessing a
broadcast of the event or task.
Value Type: URI - no default.
Property Parameters: IANA, non-standard, feature, information,
language and region property parameters can be specified on this
property.
Conformance: This property can be specified multiple times in a
"VEVENT" or "VTODO" calendar component.
Description: This property specifies information for accessing a
broadcast system for attendees of a meeting or to-do. This might
be a feed: URI [RFC3496] for a live-blog of the event, or it might
be an http: URI [RFC2616] for a web-based blog, or it might be an
rtsp: URI [RFC2326] for an audio stream.
A broadcast is expected to be a uni-directional communication
channel, as opposed to a bi-directional channel which is instead
indicated by the "CONFERENCE" property (see Section 5.11).
The "FEATURE" property parameter is used to describe the key
capabilities of the broadcast system to allow a client to choose
the ones that give the required level of interaction from a set of
multiple properties.
The "INFO" property paramater is used to convey additional details
on the use of the URI. For example, access codes for the system.
The "LANGUAGE" property parameter is used to indicate the language
associated with the property, and in particular any "INFO"
property parameter.
The "REGION" property parameter is used to indicate the region
where this property is valid. For example, an audio system could
have several streaming servers that appropriate in different
geographic regions. This property parameter can be used to
differentiate those values so that a location aware device could
pick the most appropriate one automatically.
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Format Definition: This property is defined by the following
notation:
broadcast = "BROADCAST" broadparam ":" uri CRLF
broadparam = *(
;
; The following is REQUIRED,
; but MUST NOT occur more than once.
;
(";" "VALUE" "=" "URI") /
;
; The following are OPTIONAL,
; and MUST NOT occur more than once.
;
(";" featureparam) / (";" infoparam) /
(";" languageparam) / (";" regionparam) /
;
; The following is OPTIONAL,
; and MAY occur more than once.
;
(";" other-param)
;
)
Example: The following are examples of this property:
BROADCAST;VALUE=URI;FEATURE=AUDIO;REGION=CA;rtsp://str
eam.ca.example.com/event
BROADCAST;VALUE=URI;FEATURE=AUDIO;REGION=US;rtsp://str
eam.us.example.com/event
BROADCAST;VALUE=URI;FEATURE=AUDIO;REGION=UK;rtsp://str
eam.uk.example.com/event
BROADCAST;VALUE=URI;FEATURE=FEED;INFO=Live blog:http:/
/blog.example.com/eventence.example.com
5.11. CONFERENCE Property
Property Name: CONFERENCE
Purpose: This property specifies information for accessing a
conferencing system.
Value Type: URI - no default.
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Property Parameters: IANA, non-standard, feature, information,
language and region property parameters can be specified on this
property.
Conformance: This property can be specified multiple times in a
"VEVENT" or "VTODO" calendar component.
Description: This property specifies information for accessing a
conferencing system for attendees of a meeting or to-do. This
might be a tel: URI [RFC3496] for a telephone-based conference
number dial-in (with access codes included), or it might be an
http: URI [RFC2616] for a web-based video chat, or a URI for an
instant messaging group chat room. If a specific URI for a
conferencing system is not available, a data: URI [RFC2397]
containing a text description can be used.
A conference system is expected to be a bi-directional
communication channel, as opposed to a uni-directional "feed"
which is instead indicated by the "BROADCAST" property (see
Section 5.10).
The "FEATURE" property parameter is used to describe the key
capabilities of the conference system to allow a client to choose
the ones that give the required level of interaction from a set of
multiple properties.
The "INFO" property paramater is used to convey additional details
on the use of the URI. For example, the URIs or access codes for
the moderator and attendee of a teleconference system could be
different, and the "INFO" property parameter could be used to
"tag" each "CONFERENCE" property to indicate which is which.
The "LANGUAGE" property parameter is used to indicate the language
associated with the property, and in particular any "INFO"
property parameter.
The "REGION" property parameter is used to indicate the region
where this property is valid. For example, a telephone based
conference system could have several local access numbers that are
applicable in different geographic regions. This property
parameter can be used to differentiate those values so that a
location aware device could pick the most appropriate one
automatically.
Format Definition: This property is defined by the following
notation:
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conference = "CONFERENCE" confparam ":" uri CRLF
confparam = *(
;
; The following is REQUIRED,
; but MUST NOT occur more than once.
;
(";" "VALUE" "=" "URI") /
;
; The following are OPTIONAL,
; and MUST NOT occur more than once.
;
(";" featureparam) / (";" infoparam) /
(";" languageparam) / (";" regionparam) /
;
; The following is OPTIONAL,
; and MAY occur more than once.
;
(";" other-param)
;
)
Example: The following are examples of this property:
CONFERENCE;VALUE=URI;FEATURE=AUDIO;INFO=Moderator dial-in;R
EGION=US-PA:tel:+1-412-555-0123,,,654321
CONFERENCE;VALUE=URI;FEATURE=AUDIO;INFO=Attendee dial-in;RE
GION=US-PA:tel:+1-412-555-0123,,,555123
CONFERENCE;VALUE=URI;FEATURE=AUDIO;INFO=Attendee dial-in;RE
GION=CA:tel:+1-888-555-0456,,,555123
CONFERENCE;VALUE=URI;FEATURE=CHAT;INFO=Chat room:xmpp:chat-
123@conference.example.com
6. Property Parameters
6.1. ALTURI Property Parameter
Parameter Name: ALTURI
Purpose: To specify a URI alternative to a property value.
Format Definition: This property parameter is defined by the
following notation:
alturiparam = "ALTURI" "=" DQUOTE uri DQUOTE
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Description: This property parameter MAY be specified on "IMAGE"
properties.
Example:
IMAGE;VALUE=URI;FMTTYPE=image/png:ALTURI="http://example.co
m/clicked-image1":http://example.com/images/party.png
6.2. DISPLAY Property Parameter
Parameter Name: DISPLAY
Purpose: To specify different ways in which an image for a calendar
or component can be displayed.
Format Definition: This property parameter is defined by the
following notation:
displayparam = "DISPLAY" "="
("BADGE" / ; A small "badge" image
"BACKGROUND" / ; Use as a background image
"OVERLAY" / ; Use as an overlay image
"BANNER" / ; Use as a "banner" across the top
x-name / ; Experimental type
iana-token) ; Other IANA registered type
;
; Default is BADGE
Description: This property parameter MAY be specified on "IMAGE" or
"IMAGE" properties. In the absence of this parameter, the value
"BADGE" MUST be used for the default behavior. The value
determines how a client ought to present an image supplied in
iCalendar data to the user.
Values for this parameter are registered with IANA as per
Section 8.3. New values can be added to this registry following
the procedure outlined in Section 8.2.1 of [RFC5545].
Servers and clients MUST handle x-name and iana-token values they
don't recognize by not displaying any image at all.
Example:
IMAGE;VALUE=URI;DISPLAY=BANNER;FMTTYPE=image/png:http://exa
mple.com/images/weather-cloudy.png
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6.3. FEATURE Property Parameter
Parameter Name: FEATURE
Purpose: To specify a feature or features of a conference or
broadcast system.
Format Definition: This property parameter is defined by the
following notation:
featureparam = "FEATURE" "=" featuretext *("," featuretext)
featuretext = ("AUDIO" / ; Audio capability
"CHAT" / ; Chat or instant messaging
"FEED" / ; Blog or Atom feed
"SCREEN" / ; Screen sharing
"VIDEO" / ; Video capability
x-name / ; Experimental type
iana-token) ; Other IANA registered type
Description: This property parameter MAY be specified on "BROADCAST"
or "CONFERENCE" properties.
Example:
BROADCAST;VALUE=URI;FEATURE=AUDIO:rtsp://audio.example.com/
eventCONFERENCE;FEATURE=AUDIO,VIDEO:http://video-chat.exam
ple.com/;group-id=1234
6.4. INFO Property Parameter
Parameter Name: INFO
Purpose: To specify descriptive text about a property.
Format Definition: This property parameter is defined by the
following notation:
infoparam = "INFO" "=" paramtext
Description: This property parameter MAY be specified on "BROADCAST"
and "CONFERENCE" properties.
Example:
BROADCAST;VALUE=URI;INFO=Audio stream;FEATURE=AUDIO:rtsp://
audio.example.com/event
CONFERENCE;VALUE=URI;INFO="Web video chat, access code=7654
3";:http://video-chat.example.com/;group-id=1234
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6.5. REGION Property Parameter
Parameter Name: REGION
Purpose: To specify a region or regions where a broadcast or
conference system is valid.
Format Definition: This property parameter is defined by the
following notation:
regionparam = "REGION" "=" regiontext *("," regiontext)
regiontext = paramtext ; an ISO3166-1 or ISO3166-2 code
Description: This property parameter MAY be specified on "BROADCAST"
or "CONFERENCE" properties.
Example:
CONFERENCE;VALUE=URI;FEATURE=AUDIO;INFO=Moderator dial-in;R
EGION=US-PA:tel:+1-412-555-0123,,,654321
7. Security Considerations
Several of the new properties or parameters defined by this
specification allow reference to "external" URIs. Care MUST be taken
when accessing data at external URIs as malicious content could be
present. In addition, access to those URIs could be tracked, leading
to loss of privacy.
Clients MUST by default prompt users before automatically accessing a
broadcast or conference system for the first time to prevent
attackers from being able to trigger access to a host computer simply
by sending an event invitation.
8. IANA Considerations
8.1. Property Registrations
This document defines the following new iCalendar properties to be
added to the registry defined in Section 8.2.3 of [RFC5545]:
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+------------------+---------+--------------------------------------+
| Property | Status | Reference |
+------------------+---------+--------------------------------------+
| NAME | Current | RFCXXXX, Section 5.1 |
| DESCRIPTION | Current | RFC5545 Section 3.8.1.5, RFCXXXX, |
| | | Section 5.2 |
| UID | Current | RFC5545 Section 3.8.4.7, RFCXXXX, |
| | | Section 5.3 |
| URL | Current | RFC5545 Section 3.8.4.6, RFCXXXX, |
| | | Section 5.4 |
| TIMEZONE-ID | Current | RFCXXXX, Section 5.5 |
| REFRESH-INTERVAL | Current | RFCXXXX, Section 5.6 |
| VALID | Current | RFCXXXX, Section 5.7 |
| COLOR | Current | RFCXXXX, Section 5.8 |
| IMAGE | Current | RFCXXXX, Section 5.9 |
| BROADCAST | Current | RFCXXXX, Section 5.10 |
| CONFERENCE | Current | RFCXXXX, Section 5.11 |
+------------------+---------+--------------------------------------+
8.2. Parameter Registrations
This document defines the following new iCalendar property parameters
to be added to the registry defined in Section 8.2.4 of [RFC5545]:
+--------------------+---------+----------------------+
| Property Parameter | Status | Reference |
+--------------------+---------+----------------------+
| ALTURI | Current | RFCXXXX, Section 6.1 |
| DISPLAY | Current | RFCXXXX, Section 6.2 |
| FEATURE | Current | RFCXXXX, Section 6.3 |
| INFO | Current | RFCXXXX, Section 6.4 |
| REGION | Current | RFCXXXX, Section 6.5 |
+--------------------+---------+----------------------+
8.3. Display Types Registry
This document defines the following new iCalendar value registry as
per Section 8.2.6 of [RFC5545]:
+--------------+---------+----------------------+
| Display Type | Status | Reference |
+--------------+---------+----------------------+
| BADGE | Current | RFCXXXX, Section 6.2 |
| BACKGROUND | Current | RFCXXXX, Section 6.2 |
| OVERLAY | Current | RFCXXXX, Section 6.2 |
| BANNER | Current | RFCXXXX, Section 6.2 |
+--------------+---------+----------------------+
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8.4. Feature Types Registry
This document defines the following new iCalendar value registry as
per Section 8.2.6 of [RFC5545]:
+--------------+---------+----------------------+
| Feature Type | Status | Reference |
+--------------+---------+----------------------+
| AUDIO | Current | RFCXXXX, Section 6.3 |
| CHAT | Current | RFCXXXX, Section 6.3 |
| FEED | Current | RFCXXXX, Section 6.3 |
| SCREEN | Current | RFCXXXX, Section 6.3 |
| VIDEO | Current | RFCXXXX, Section 6.3 |
+--------------+---------+----------------------+
9. Acknowledgments
Thanks to the following for feedback: Bernard Desruisseaux, Mike
Douglass, Arnaud Quillaud, and Dave Thewlis. This specification came
about via discussions at the Calendaring and Scheduling Consortium.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234, January 2008.
[RFC5545] Desruisseaux, B., "Internet Calendaring and Scheduling
Core Object Specification (iCalendar)", RFC 5545,
September 2009.
10.2. Informative References
[RFC2326] Schulzrinne, H., Rao, A., and R. Lanphier, "Real Time
Streaming Protocol (RTSP)", RFC 2326, April 1998.
[RFC2397] Masinter, L., "The "data" URL scheme", RFC 2397,
August 1998.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
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[RFC3496] Malis, A. and T. Hsiao, "Protocol Extension for Support of
Asynchronous Transfer Mode (ATM) Service Class-aware
Multiprotocol Label Switching (MPLS) Traffic Engineering",
RFC 3496, March 2003.
[RFC5546] Daboo, C., "iCalendar Transport-Independent
Interoperability Protocol (iTIP)", RFC 5546,
December 2009.
Appendix A. Change History (To be removed by RFC Editor before
publication)
Changes in -05:
1. Added section with recommendation on handling extension
properties.
2. Added VALID property.
Changes in -04:
1. TZID changed to new property TIMEZONE-ID.
2. Minor formal syntax changes.
Changes in -03:
1. Dropped CALENDAR- prefix
2. DESCRIPTION, UID and TZID now based on existing RFC5545
properties
3. COLOR now on both the calendar and component level
4. IMAGE now on both the calendar and component level
5. Added FEATURE and REGION parameters to CONFERENCE property
6. Added ALTURI parameter to IMAGE property
7. Added FEED value to FEATURE parameter
8. Added BROADCAST property and clarified that CONFERENCE is for bi-
direction channels and BROADCAST is for uni-directional.
Changes in -02:
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1. Minor wording changes.
2. Interval is now described as the "minimum interval".
3. Added CONFERENCE property and INFO parameter.
Changes in -01:
1. Fixed DISPLAY parameter handling of x- and iana tokens to state
that clients ignore the image if the token is not recognized.
2. Allow language variants for CALENDAR-NAME and CALENDAR-
DESCRIPTION.
3. Added registry for DISPLAY values.
Author's Address
Cyrus Daboo
Apple Inc.
1 Infinite Loop
Cupertino, CA 95014
USA
Email: cyrus@daboo.name
URI: http://www.apple.com/
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