[Odrl-version2] Common Vocabulary - Constraints on Duties

[ri at odrl.net]

On 15 Jun 2011, at 22:27, Francis Cave wrote:

> Hmm... I had intended case 1 to mean that you are permitted to make only one
> copy EVER, and must obtain consent first, not one copy after each time you
> obtain consent.

More Hmmm.....that is what this use cases does (assume it was part of an Agreement):
  Perm.Action.Copy
  Constraint.Count.eq.1
  Duty.Action.obtainConsent
It says you can Copy once, after getting the Consent - and that's it.
The "Policy Management" enforcement engine would decrement the counter (now = 0) and you can no longer Copy.
(if you want more, then u need to enter into a new agreement).

The use case "one copy after each time you obtain consent" is interesting....

I can see this being expressed thru the recursive use of nextPolicy:

  Policy.Agreement.Id.001
    Perm.Asset.target=http://ex.com/report.pdf
    Perm.Action.Copy
    Constraint.Count.eq.1
    Duty.Action.obtainConsent

    Perm.Asset.target=http://ex.com/report.pdf
    Perm.Action.NextPolicy
    Perm.Asset.nextPolicy=agreement.Id.001

(This is a new use of nextPolicy as a Permission - usually used as a Duty - and hence the new Asset Relation)

More hmmmm.....!

Cheers

Renato Iannella
ODRL Initiative
http://odrl.net