STIX Enhancements

All,

I would like to kick of a thread here to discuss some of the STIX Enhancement pieces that I feel we need to address.  Please note, the STIX Enhancement work is not the same as the STIX Work Product Process document that
 I sent out a few weeks earlier.  These are different things.

In order for STIX Enhancements (or what some might call a protocol or schema extension) to work it is my belief that a STIX Object that contains an enhancement needs a way of saying that it contains one or more enhancements. 
 Further, I also believe there needs to be some very basic elements added to TAXII to be able to identify that a client and server both support certain enhancements. On the STIX schema side I view this as something like:

{

   type: "indicator",

   ...

   seps: [

      "enhancement_foo",

      "enhancement_bar_123"

   ],

   ...rest of indicator...

}

There has been some discussion about if SEPs should be versioned or if each SEP version should be its own thing.  I have not seen enough pros and cons to personally decide what I would prefer.  Also, the list of SEPs
 may need to be a list of objects instead of a list of strings.

Bret