Peter Williams writes:
Getting a suitable typed information model formalized was never very
hard. That MIME does this part in a very natural and
self-defining/implementing way is great; the smalltalk for the
common-man! That in combination with message passing protocols
(providing LOCATION-INDEPENDENT, DOMAIN-INDEPENDENT connectionless
private channels) wonderful groupware concepts can be
defined/implemented whose application semantics and flows are specified
in the very object being passed. The fault lines with MIME are that it
only allows in one-pass but one organization of the content objects to
be specified. (Im willing to be corrected here... I may be either
wrong, or its all in the original conception as yet unfulfilled)
Its the latter - there are mechansims in MIME (e.g. content-id fields) that
allow for the construction of essentially arbitrary structures. However, the
problem with such structures isn't providing facilities to define them, its
finding short-term real-world uses that are readily implementable. A killer
application, in other words. Thus far it looks like the folks doing SGML
packages in MIME are going to be the first to get this far, although of course
that could change at any time.
The point being, of course, that the structures are there but presently unused.
Security services add additional capabilities to the existing structure, and
may provide the necessary push to get more complex uses going.
Ned