Subject: [Ietf-calsify] RE: [Ietf-caldav] comments on -02

From: TimHare at comcast.net ([email-masked])
Date: Wed Oct 6 19:30:38 2004

Free/Busy is a property of the user/owner of the calendar more than 
anything else; in essence I really want a logical AND of all of my 
free/busy time so that none of my events, personal or business, get 
overbooked. In iCalendar, however, we have to represent those at the 
VCALENDAR level.  I am cross-posting this to the calsify list, because it 
really belongs there - my view is that we ought to establish a standard for 
the granularity of a free/busy time map (15 minutes would be my choice), 
and then just exchange a "bit map" of the time between two dates that are 
requested as the endpoints - call it a VBUSYMAP deliverable as other binary 
objects are, in Base64.  Then, scheduling a meeting might go something like 
this:

Organizer to each attendee: Show me your free/busy map between date X and 
date Y.
Each attendee: here is the VBUSYMAP of my time
Organizer then finds (hopefully) a time when all are free, and sends out 
meeting requests for that time;or, finding no acceptable time, picks two 
different dates and tries again.

This, to me, simplifies and shortens the scheduling process. Your code 
doesn't have to parse all of the VFREEBUSY items. In fact, an 
implementation can choose to maintain the map in whatever backing store it 
uses, and keep it updated as VEVENTS are added or removed.

At 08:36 PM 10/6/04, Cameron Stillion wrote:
>But if you don't want to be scheduled, that means you want the time to
>appear as if you are "scheduled" already... Right?  You can do this now
>by putting an appointment on your calendar marked as "OOF" - and the
>free/busy view of this event will clearly mark this as already taken.
>
>Having someone schedule you on Saturday or Sunday is really a social
>problem though. If it is your wife, it makes sense.  If it's your
>co-worker, then there are social checks and balances that say this won't
>happen if it isn't appropriate.  The protocol is not meant to solve the
>social aspect.  Clearly good software would keep this in mind and help
>you do the right thing, but it can't know all the human implications...
>
>I still stand by the fact that free/busy is merely a translation of
>events, and that anything else is unnecessarily complex with really no
>benefit - to the standard most especially, but even more to applications
>and systems.
>
>
>cameron
>
>
>-----Original Message-----
>From: [email-masked]
>[mailto:[email-masked]] On Behalf Of G. Barnes
>Sent: Wednesday, October 06, 2004 10:26 AM
>To: [email-masked]
>Subject: Re: [Ietf-caldav] comments on -02
>
>On Wed, 6 Oct 2004, Lisa Dusseault wrote:
>
> > I could go either way on allowing users to store standalone VFREEBUSY
> > components.  Keeping it is a small feature/flexibility; removing it is
>
> > a small simplification.  Who else has use cases or problems with
> > keeping or removing that feature?
>
>I have a problem with removing it.  I want to be able to say, 'no one
>can schedule me on Saturday or Sunday' (among other times).  Othewise,
>some jerk is going to schedule a mandatory meeting at 7am Saturday.
>Creating a VEVENT would presumably mean something shows up in my
>calendar.
>But I don't necessarily have an event scheduled; I just want to be left
>alone.  The most obvious way to do this is to create a standalone
>VFREEBUSY.
>
>                    Greg Barnes
>                    Computing and Communications, University of
>Washington
>                    [email-masked]
>                    (206) 685-3295
>_______________________________________________
>Ietf-caldav mailing list
>[email-masked]
>http://lists.osafoundation.org/mailman/listinfo/ietf-caldav
>
>_______________________________________________
>Ietf-caldav mailing list
>[email-masked]
>http://lists.osafoundation.org/mailman/listinfo/ietf-caldav

Tim Hare
Interested Bystander, Non-Inc.

---

From: lisa at osafoundation.org (Lisa Dusseault)
Date: Wed Oct 6 20:44:34 2004

I don't see why a bit map has any advantages over a free busy summary 
with begin/end times for each busy blocks.  And the begin/end 
timestamps have some advantages: they're human-readable (or at least 
developer/debugger readable), and don't require us to choose an 
arbitrary maximum granularity (why fifteen minutes? why not five? one?  
Can I negotiate granularity?).

The calendar agent can always translate begin/end times into a bitmap 
for summarization -- that's implementation-dependent.

I have a prejudice against binary formats, too :)

Lisa

On Oct 6, 2004, at 7:25 PM, [email-masked] wrote:

> VCALENDAR level.  I am cross-posting this to the calsify list, because 
> it really belongs there - my view is that we ought to establish a 
> standard for the granularity of a free/busy time map (15 minutes would 
> be my choice), and then just exchange a "bit map" of the time between 
> two dates that are requested as the endpoints - call it a VBUSYMAP 
> deliverable as other binary objects are, in Base64.  Then, scheduling 
> a meeting might go something like this:
>
> Organizer to each attendee: Show me your free/busy map between date X 
> and date Y.
> Organizer then finds (hopefully) a time when all are free, and sends 
> out meeting requests for that time;or, finding no acceptable time, 
> picks two different dates and tries again.
>
> implementation can choose to maintain the map in whatever backing 
> store it uses, and keep it updated as VEVENTS are added or removed.
>

---

From: Doug at Royer.com (Doug Royer)
Date: Thu Oct 7 10:36:22 2004

Lisa Dusseault wrote:

> arbitrary maximum granularity (why fifteen minutes? why not five? 
> one?  Can I negotiate granularity?).

I agree. VFREEBUSY is already in effect a bit map represented in ASCII.

> ...

-- 

Doug Royer                     |   http://INET-Consulting.com
-------------------------------|-----------------------------
[email-masked]                 | Office: (208)520-4044
http://Royer.com/People/Doug   | Fax:    (866)594-8574
                               | Cell:   (208)520-4044

              We Do Standards - You Need Standards

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From: lyndon at orthanc.ca (Lyndon Nerenberg)
Date: Sat Oct 9 21:57:21 2004

--On 2004-10-6 10:25 PM -0400 [email-masked] wrote:

> my view is that we ought to establish a standard for the granularity
> of a free/busy time map (15 minutes would be my choice)

I disagree with this. Calendaring is much more than just scheduling 
meetings (with people). I can see using iCal and friends to schedule 
runtime on computing clusters, or access to radio astronomy telescopes, 
or many other resources where fine-grained access times are 
appropriate. We should not be placing any form of social restrictions 
on the protocols like this. They must be left as open ended as possible 
so as to preclude us having to revisit the specifications in the near 
term because we didn't anticipate a use for them.

--lyndon

---

From: TimHare at comcast.net ([email-masked])
Date: Sun Oct 10 05:57:06 2004

After several comments, I can see that exchanging a "bit map" of free/busy 
time has definite downsides,  so let's drop that idea.
Also, rather than continuing to cross-post I will put further discussion of 
how to simplify free/busy work  on the calsify list rather than caldav.

Tim Hare