RE: MIME Multiple body parts (Was Re: uid...)

["John Stracke" <jstracke@xxxxxxxxxxxxxxxxxxxx>]

>1 - are we discussing a MULTIPART composed of iCalendar related objects?
>(some encrypted, some not perhaps?)

Only if we adopt Bruce's suggestion of having some fields encrypted and 
others not (this could be done by the multipart/alternative approach I 
mentioned).

>2 - are we discussing a MULTIPART composed of a text or text/html object 
+
>an iCalendar object?

I think so.  For example, it will probably be common to send a 
multipart/mixed containing a text/plain and an text/calendar.  (Less 
common, because it's broken, is the approach taken by Microsoft Entourage: 
a multipart/alternative containing first the text/calendar and then the 
text/html.  A recipient that understands text/html will never see the 
text/calendar.)

>Also - if the iCalendar object has say an Attachment - are we considering
>allowing that ATTACHMENT to be bundled as part of the MULTIPART message,
>and/or for that ATTACHMENT to be encrypted in some manner?

Strictly speaking, it's permitted by RFC-2445; the ATTACH is specified by 
a URL, so you can use a cid: to reference bodyparts.  Whether a CAP server 
would deal with it is another question.

As a practical matter, sending an iMIP message with a cid: attachment is 
probably risky.  It's easy for a recipient's MUA to take the text/calendar 
and pass it off to the CUA for processing; but permitting the CUA to go 
back to the MUA to resolve the cid: URL requires more integration.  It'd 
be trivial for an app that combines the CUA and the MUA (e.g., Evolution, 
Outlook, Notes), but not for independent apps.

/================================================================\
|John Stracke                    |Principal Engineer             |
|jstracke@xxxxxxxxxxxxxxxxxxxx   |Incentive Systems, Inc.        |
|http://www.incentivesystems.com |My opinions are my own.        |
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|"The struggle is always worthwhile, if the end be worthwhile and|
|the means honorable; foreknowledge of defeat is not sufficient  |
|reason to withdraw from the contest." -- Adron e'Kieron, by     |
|Steven Brust                                                    |
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