CalDAV clients MUST support inline attachments as specified in iCalendar [RFC2445]. CalDAV servers MUST support inline attachments, so clients can rely on being able to create attachments this way. On the other hand, inline attachments have some drawbacks:
o Servers MAY impose limitations on the size of calendar object resources (i.e., refusing PUT requests of very large iCalendar objects). Servers that impose such limitations MUST use the CALDAV:max-resource-size property on a calendar collection to inform the client as to what the limitation is (see Section 5.2.5).
o Servers MAY impose storage quota limitations on calendar collections (See [RFC4331]).
o Any change to a calendar object resource containing an inline attachment requires the entire inline attachment to be re- uploaded.
o Clients synchronizing a changed calendar object resource have to download the entire calendar object resource, even if the attachment is unchanged.