[Ietf-calsify] Section 4.6.1 Event Component: Default duration of day events

[Cyrus Daboo]

Hi Bernard,

--On November 5, 2006 5:26:48 PM -0500 Bernard Desruisseaux 
<bernard.desruisseaux at oracle.com> wrote:

> In section 4.6.1 Event Component of RFC 2445 it says:
>
>  > For cases where a "VEVENT" calendar component specifies a "DTSTART"
>  > property with a DATE data type but no "DTEND" property, the events
>  > non-inclusive end is the end of the calendar date specified by the
>  > "DTSTART" property.
>
> As such, the last sentence of the paragraph before the following example
> is wrong. This event would actually appear as opaque in a search for busy
> time.
>
>  > The following is an example of the "VEVENT" calendar component used
>  > to represent an anniversary that will occur annually. Since it takes
>  > up no time, it will not appear as opaque in a search for busy time;
>  > no matter what the value of the "TRANSP" property indicates:
>  >
>  >   BEGIN:VEVENT
>  >   UID:19970901T130000Z-123403 at host.com
>  >   DTSTAMP:19970901T1300Z
>  >   DTSTART:19971102
>  >   SUMMARY:Our Blissful Anniversary
>  >   CLASS:CONFIDENTIAL
>  >   CATEGORIES:ANNIVERSARY,PERSONAL,SPECIAL OCCASION
>  >   RRULE:FREQ=YEARLY
>  >   END:VEVENT
>
> I propose to remove this sentence and to add the TRANSP property to
> the example.
>
> Proposed text:
>
>  > The following is an example of the "VEVENT" calendar component used
>  > to represent an anniversary that will occur annually.
>  >
>  >   BEGIN:VEVENT
>  >   UID:19970901T130000Z-123403 at host.com
>  >   DTSTAMP:19970901T1300Z
>  >   DTSTART:19971102
>  >   SUMMARY:Our Blissful Anniversary
>  >   TRANSP:TRANSPARENT
>  >   CLASS:CONFIDENTIAL
>  >   CATEGORIES:ANNIVERSARY,PERSONAL,SPECIAL OCCASION
>  >   RRULE:FREQ=YEARLY
>  >   END:VEVENT
>
> Similarly, in section 4.8.2.4 Date/Time Start of RFC 2445 it says:
>
>  > Description: Within the "VEVENT" calendar component, this property
>  > defines the start date and time for the event. The property is
>  > REQUIRED in "VEVENT" calendar components. Events can have a start
>  > date/time but no end date/time. In that case, the event does not take
>  > up any time.
>
> I propose to remove the last two sentences of this paragraph.
>
> Proposed text:
>
>  > Description: Within the "VEVENT" calendar component, this property
>  > defines the start date and time for the event. The property is
>  > REQUIRED in "VEVENT" calendar components.
>
> Finally, in section 6 Recommended Practices of RFC 2445 it says:
>
>  > 2.  A calendar entry with a "DTSTART" property but no "DTEND"
>  >     property does not take up any time. It is intended to represent
>  >     an event that is associated with a given calendar date and time
>  >     of day, such as an anniversary. Since the event does not take up
>  >     any time, it MUST NOT be used to record busy time no matter what
>  >     the value for the "TRANSP" property.
>
> This is actually wrong. I would simply remove this text. The proper
> behave is described in section 4.6.1 Event Component.

This issue begs the question of whether all day events should automatically 
appear as opaque in free-busy lookups. I suspect most implementations do 
not add TRANS:TRANSPARENT when adding an 'anniversary' event - but having 
that block out time would be bad.

This would be a change to 2445, but one solution is to say the default 
TRANSP for all day events is TRANSPARENT rather than OPAQUE.

-- 
Cyrus Daboo