Who is Visible: Resolving Access Policy Conflicts in Online Social Networks

Millions of the co-owned items, such as photos, comments etc., are uploaded to OSNs everyday. These co-owned items contain plenty of privacy information. One important information is the social relations which can be inferred from the items. When sharing these items, the owners may just want to make themselves visible alone while hiding these social relations. It leaves us a problem that making each single co-owner visible alone is acceptable, but showing them together is not allowed. To avoid the privacy leakage, we should choose proper owners to be visible to the visitor. Unfortunately, traditional access control for OSNs cannot fit this concern thus cannot provide a suitable answer. To deal with this problem, we first define the 'dislike relation' and its corresponding conflicts. Then we propose a communication-intensity-based scheme to measure the social intimacies between the visitor and co-owners of the accessed item. Based on the social intimacies, we can provide a decision support when conflicts occur. Case studies and user studies are performed to illustrate the effectiveness of our proposed scheme.