Exploring the viability of tie strength and tags in access controls for photo sharing.

Social Network Sites (SNSs) such as Facebook and Google+ allow users to store and share large collections of photos. SNSs offer access controls that protect those photos from unwanted audiences. However, due to the lack of usability of these access controls, people struggle to configure them. First, we collected sharing policies for photos in a study with 34 Facebook users. Then, we define three metrics that enable researchers to evaluate the ease of use and complexity of access controls for photo sharing, and, employing the data collected in the study, we evaluate 15 access controls, each one with a different combination of attributes. The results obtained show that an access control that takes into account groups, tags, and the tie strength of relationships can be managed more easily than current approaches, reducing the burden of configuring the privacy settings for photos on SNSs.