Subject: RE: How to use CAP for scheduling events.

From: Frank Dawson/CAM/Lotus <[email-masked]>
Date: Wed, 26 May 1999 01:57:10 GMT

Pete:

I agree that "calendaring" operations are different than "scheduling"
operations. We spent considerable time at the last interim IETF CALSCH WG
meeting in Atlanta working through scenarios for both calendaring
management and scheduling. It appeared to make sense that sending iTIP
commands (or at least iTIP-Plus) was an expedient mechanism to providing
scheduling functionality in CAP.

While I agree with you that CREATE, READ, MODIFY, UPDATE, DELETE methods
are distinct from the iTIP methods, there appears to be some merit to
including both sets of scheduling and calendaring operations in CAP.

Just work through the CAP prototype for replying to a meeting invitation.
It is much more "hairy" an operation if you decompose the atomic nature of
an iTIP "REPLY" method. Certainly, you _could_ do this in CAP with the
"calendar management" functions. But, it is more complex.

We also are beginning to recognize that a CAP compliant implementation
needs to be able to send iTIP (at least iMIP) messages anyway. There are
some folks that may reside inside firewalls or only have iMIP addresses (in
the short term). Hence, we are thinking that a CAP compliant CS
implementation needs to be able to accept iMIP "MAILTO" addresses, in
addition to the preferred CAP URLs.

A third rationale that, I think, Doug Royer has raised is that the calendar
access rights picture is simplified by introducing iTIP (or at least
iTIP-Plus) methods to CAP.

Allowing iTIP methods in CAP also clarifies the relationship between iTIP
and CAP, which for me has been most obscure, up to this point. All of our
diagrams of protocol models seems to have CAP and iTIP as disjoint
protocols. Yet, from my experience with two previous calendaring standards,
there is a complementary relationship between scheduling and calendar
management. There really needs to be clearer and tighter coupling between
iTIP and CAP. I firmly believe that this provides that clarity and strong
relationship. Most of all, it makes sense to both us implementors and also
the customers and analysts that I have spoken with.

I agree with all of these arguments for including iTIP (or at least
iTIP-Plus) methods into CAP.

-- Frank