Re: [xacml] Issue#12: Obligations: Chronicle Attribute

[Bill Parducci <bill.parducci@simulalabs.com>]

On May 25, 2007, at 11:24 PM, Erik Rissanen wrote:

> The argument for having the chronicle part of the family is that the
> chronicle attribute may be in conflict with attributes of a family. I
> see family types as means of collecting consistent attributes of
> obligations. Conflicting attributes go into separate family types.  
> If we
> put the chronicle attribute into the obligation itself, it will
> effectively end up in all families, and potentially conflict with
> another attribute somewhere.
>
> For instance, the sequential family specifies an order of obligations
> enforcement. This order could be in conflict with the order implied by
> the chronicle attributes. Well, in this case it is simple to  
> resolve by
> just saying that the chronicle has priority, but could there be some
> more difficult problem?
>
> Overall I think I am leaning towards putting the chronicle into the
> obligation, not the family, but I will think more about this.
>

Good points, but I think that applying timing to each Family in an  
atomic sense would solve this. In such a situation the reduced Family  
members would be applied as directed by the Families Attributes  
together, in total, as directed by the Chronicle Attribute. This is  
just my first thought but the reasoning behind creating the Families  
was to bubble up Obligation Attributes to [try to] avoid such conflicts.

Unfortunately , this approach raises issues with possible  
combinations but I think we may be able to put some descriptive  
constraints in place that may address both problems (e.g. "Exclusive  
may not be used with Repetitive", etc.)

b