Re: privacy in OWL

On Thu, May 01, 2003 at 09:53:12AM -0500, Dan Connolly wrote:
> If you have any comments on it, please send them
> to public-webont-comments@w3.org


Comment on Privacy in Web-ont

It is honorable, that the Webont Working Group thought about 
including something about Privacy into their guide. 

<for the impatient>
As usual in privacy, nearly everybody is aware of potential
privacy issues or has some kind of bad conciousness about it.
In the absence of real solutions, this bad consciousness is
discharged by some rather general privacy warning. The result is
that implementers of OWL will share bad consciousness, but lack a
solution. 

The good news is, that there might be some remedy. The remedy
lies in OWL itself, as the approach is mainly based on metadata.
The P3P Specification WG has thought about integrating the P3P
semantics into the Semantic Web. For this reason -in cooperation
with the RDF IG- a RDF-Schema representing P3P was developed[1]. It
might be good to reference this schema and verify, whether it is
importable into OWL (or what is missing/has to be changed,  
to make it importable). This way, OWL-Ontologies treating persons
would be able to also include those persons' preferences. This
way, the inference engine can respect those preferences (or
policies attached to an individual). 

In the future, we might want to use the preference-language
APPEL[2] but I'm actually not able to determine if it would
better fit into OWL.
</for the impatient>

I would suggest the following text. You can still change it as
you like:

OWL's ability to express ontological information about
individuals -even appearing in multiple documents-, it's 
support for linking of data about individuals from diverse 
sources in a principled way may raise privacy issues. 
Privacy, by it's definition, protects individuals. Only if
dealing with natural persons, one must be aware of the privacy
implications. Goal is to protect against the disclosure of
sensitive personal data but also against the creation of profiles
making the individual and it's personality completly transparent
to others. If we talk about privacy, we want to the opaqueness of
someones personality and intimacy to the outside world. This can
be overturned by the individual's will to disclose information.
As a consequence, there is a need for the individuals kept in an
ontology to be able to express their preferences. This can be
done using the RDF-syntax for P3P [link] or APPEL [link]. 

In particular, the ability to express equivalences using
owl:sameIndividualAs can be used to state that seemingly
different individuals are actually the same.
Owl:InverseFunctionalProperty can also be used to link
individuals together. For example, if a property such as
"SocialSecurityNumber" is an owl:InverseFunctionalProperty, then
two separate individuals could be inferred to be identical based
on having the same value of that property. When individuals are
determined to be the same by such means, information about them
from different sources can be merged. This aggregation can be
used to determine facts that are not directly represented in any
one source. 

The ability of the Semantic Web to link information from multiple
sources is a desirable and powerful feature that can be used in
many applications. However, the capability to merge data from
multiple sources, combined with the inferential power of OWL,
does have potential for abuse. Users of OWL should be alert to
the potential privacy implications.



  1. http://www.w3.org/TR/p3p-rdfschema/
  2. http://www.w3.org/TR/P3P-preferences/

Best, 

-- 
Rigo Wenning            W3C/ERCIM
Policy Analyst          Privacy Activity Lead
mail:rigo@w3.org        2004, Routes des Lucioles
http://www.w3.org/      F-06902 Sophia Antipolis

Received on Tuesday, 6 May 2003 09:45:07 UTC