Pay Per Use

At the last meeting [1] in discussion for UC.10 [2] Pay Per Use, I was tasked to looking into the current ODRL support for this requirement.

ODRL is vague as to when a Duty must be actioned (as we expect that to be explicitly expressed).

In ODRL V2, we introduced a constraint called “event” to support exercising policies over a specified period (eg Rio Olympics)
We also included a specific value of “policyUsage” [3] that is the period whilst the policy is being exercised.

This then meant you could say that a Duty (eg a compensate payment) must be made *before* the policy can be exercised (eg before you play the movie).

So, in order to say you can play a movie (once and only once) and pay $1 each time (before playing the movie), then you would need to add the "constraint=1" to the Permission “play” then add a "event lt o:policyUsage” to the Duty “compensate”.


Renato Iannella, Monegraph
Co-Chair, W3C Permissions & Obligations Expression (POE) Working Group

[1] https://www.w3.org/2016/08/01-poe-minutes <https://www.w3.org/2016/08/01-poe-minutes>
[2] https://www.w3.org/TR/poe-ucr/#payByUse <https://www.w3.org/TR/poe-ucr/#payByUse>
[3] https://www.w3.org/TR/vocab-odrl/#term-policyUsage <https://www.w3.org/TR/vocab-odrl/#term-policyUsage>