Re: [emergency-cap-profiles] profile proliferation

["Art Botterell" <ABott@so.cccounty.us>]

Again I'd stress that profiles aren't devised by message originators for
their own purposes, but rather are used to document special requirements
of particular message consumers.  If a particular consumer or consumers
(e.g., IPAWS) wants to specify what it/they need(s) to see in a message,
it/they can publish a profile.  Then originators may choose to implement
or not implement that profile, depending on how important satisfying
that particular consumer or consumers is to them.

Strictly speaking a data dictionary defines semantics, while a schema
specifies syntax.  (In practice a data dictionary may mention syntactic
rules as well, but the schema is generally viewed as definitive on
syntax.)  So a profile might include a data dictionary, a schema or
depending on what's being constrained.  (Or even "neither" if the
particular constraints in question are simple enough to be described
without resorting to a full-blown dictionary or schema.)  

For example, a rule that there can only be one info block (NOT a
recommendation, only an example!) might be expressed best in a schema,
whereas a rule that says info blocks shall only be used for versions of
the same message in different languages (again, only for example) would
be a semantic constraint best addressed in data dictionary style.

As for a dictionary of agreed semantics within an application domain,
that would need to be defined by the subject matter experts.  For
example, we here aren't seismologists.  That's how EDXL approaches
various versions of this same problem, and that's why I think the real
answer here is to move CAP toward EDXL integration without perpetrating
in any more profiles than are absolutely necessary in the meantime.

- Art



Art Botterell, Manager
Community Warning System
Contra Costa County Office of the Sheriff
50 Glacier Drive
Martinez, California 94553
(925) 313-9603
fax (925) 646-1120