Re: Resolution 23

Hi!


> A similar question can be asked for the (actual) use case for
> AND/OR/XOR for Duties and Constraints.

The current ODRL Spec describes the relationship between Permissions and 
Duties as follows [1]:

"[...] If a Permission refers to several Duty entities, all of them MUST 
be fulfilled for the Permission to become valid. [...]"

Which allows to express things like:
  -> "If you pay me 50€, I grant you the permission to use my dataset."
  -> "If you pay me 100€, I grant you the permission to distribute my 
dataset, but you have to delete it after 30 days."

However, there may be situations where an assigner wants to assign 
multiple Duties to a Permission where the fulfillment of each individual 
Duty on its own would entitle someone to exercise respective Permission.

For example:
  -> "If you pay me 50€ or 71AUD or 45GPB, I grant you the permission to 
use my dataset." (XOR)
  -> "If you pay me 100€, I grant you the permission to distribute my 
dataset, but you have to delete it after 30 days. If you pay me 1000€, 
however, I grant you the permission to distribute my dataset without 
requiring you to delete it after 30 days." (OR)

And yes, to some extend one could already express those examples in 
ODRL, e.g., using multiple Permissions (ignoring conflict resolution):

---------------------------
odrl:permission [
     odrl:action odrl:use;
     ...
     odrl:duty ex:pay50Euro ].

odrl:permission [
     odrl:action odrl:use;
     ...
     odrl:duty ex:pay71AUD ].

odrl:permission [
     odrl:action odrl:use;
     ...
     odrl:duty ex:pay45GPB ].
---------------------------

---------------------------
odrl:permission [
     odrl:action odrl:distribute;
     ...
     odrl:duty ex:pay100EURdelete30D ].

odrl:permission [
     odrl:action odrl:distribute;
     ...
     odrl:duty ex:pay1000EUR ].
---------------------------

Which may work for OR semantics, but certainly not for XOR. Especially, 
when considering the potential future addition of Remedies to ODRL 
requiring the possibility to express things like "a $500 fine or ten 
days in jail".

Constraints on the other hand are a complete different story and need to 
be discussed separately.

br,
simon

[1] https://w3c.github.io/poe/model/#duty
[2] https://www.w3.org/2016/poe/wiki/Requirements#POE.R.DM.11_Remedies
---
DDipl.-Ing. Simon Steyskal
Institute for Information Business, WU Vienna

www: http://www.steyskal.info/  twitter: @simonsteys

Am 2016-10-19 04:01, schrieb Renato Iannella:
> At the last teleconference [1], resolution 23 stated:
> 
> "That the extended relations (AND, OR, XOR) will only apply to Duties
> and Constraints, not Permissions and Prohibitions"
> 
> And Simons comment [2]:
> 
> "Besides that, I'm actually wondering whether there's any use case
> that would motivate/require AND-/OR-/XOR-ing
> Permissions/Prohibitions?”
> 
> A similar question can be asked for the (actual) use case for
> AND/OR/XOR for Duties and Constraints.
> 
> That was the outcome from the TPAC meeting - more concrete use cases
> for all cases of Extended Relations.
> 
> (Historical Note: we removed extended relations for ODRL V2.0 as
> implementors felt they were difficult to engineer, and there were no
> examples of its use. It was decided that this level of logic was
> application-specific, that is, once the “relation” decision has
> been captured by the “system”, the the concrete ODRL expressions
> could be created for each case.)
> 
> Renato Iannella, Monegraph
> Co-Chair, W3C Permissions & Obligations Expression (POE) Working Group
> 
> 
> [1] https://www.w3.org/2016/10/17-poe-minutes [1]
> [2] https://github.com/w3c/poe/issues/45 [2]
> 
> Links:
> ------
> [1] https://www.w3.org/2016/10/17-poe-minutes
> [2] https://github.com/w3c/poe/issues/45

Received on Wednesday, 19 October 2016 07:14:25 UTC