[Odrl-version2] Constraints on duties - I think I've got it now...

[Alapan Arnab]

Hi,

> I wonder if duties should have (optional) consequences.  For example, maybe
> the agreement owner would like to say "Alice may lock f.src; she should
> return the lock within 24 hours, and, if she doesn't return the lock, then
> she'll be charged one Euro a day".  More generally, relaxed duties allow
> obligations to hold after the right has been granted/exercised, so I think
> it'd make sense (and is often the case in practice) for there to be
> consequences to unmet obligations.  What do you think?  
> 
I think this is a great idea, and should be a part of duties. 
> -----
> 
> Party=Alice, Bob
> Perm= download 
> Asset= F
> Duty= pays 1 euro
> Duty.Constraint= user is over 21
> Duty.Relax = false
> 
> This means (1) if Alice is over 21, then she may pay 1 euro and, if she pays
> the euro, then she may download F.  The same is true for Bob.  So the
> agreement is equivalent to one that says "Alice/Bob may download F if she/he
> is over 21 and pays a euro".  That is, the agreement is equivalent to
> 
> Party=Alice, Bob
> Perm= download 
> Asset= F
> Duty= pays 1 euro
> Perm.Constraint= user is over 21
> Duty.Relax = false
> 
Not sure what is the difference between the two.
> ----
> (This one's really about parties v. individuals.)
> 
> Party=Alice 
> Perm= download 
> Asset= F
> Duty= pays 1 euro
> Duty.Assignee = {Alice, Bob}
> Duty.Beneficiary = {Charlie, Dan}
> Duty.Relax = false
> 
> The agreement says that Alice may download F if {Alice, Bob} has paid 1 euro
> to {Charlie, Dan}.  Suppose Bob gives a euro to Charlie.  Then does it
> necessarily follow that {Alice, Bob} has given a euro to {Charlie, Dan} and,
> thus, Alice may download F?  
> 
Yes, as long as Bob was paying 1 Euro for the purpose of Alice
downloading (and not for something else). 

Alapan
-- 
Alapan Arnab
Data Networks Architecture (DNA) Laboratory
Department of Computer Science
University of Cape Town
Rondebosch, 7700
South Africa

Tel: +27 21 650 3127
Web: http://people.cs.uct.ac.za/~aarnab/
Blog: http://idiots-mind.blogspot.com
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