With the expression social collaboration we refer to the processes of helping multiple
people to interact and share information in order to achieve common goals.
Nowadays, collaboration and social dissemination of information are facilitated by
the Internet and Social Network Services (SNS). The reliance of social collaboration
on SNS might seem surprising given the differences between their group-centric
and individual-centric views. In particular, social collaboration services focus on
group activities, identifying groups and collaboration spaces in which messages are
explicitly directed at the group and the group activity feed is seen the same way by
everyone. In contrast, social networking services generally focus on single personalized
activities, sharing messages in a more-or-less undirected way and receiving
messages from many sources into a single personalized activity feed.
Despite these differences, in current digital society a convergence between mass
communication and personal communication is leading to social and community
uses of online social network services. This is because the present use of social
media has grown enormously, moving from a niche phenomenon to mass adoption
(Gross and Acquisti 2005 ). For these reasons, it emerges how social interactions on
the online world must not be considered as separated entities with respect to collaborating
communities in the real (offl ine) world. In this scenario, it often comes to light
how current social network services architectures do not allow to treat and analyze
communities and their privacy issues in the online world as really happens in the
offl ine world. This is due, in particular, to the fact that the online world often does not have the same boundaries and does not follow the same social norms which are
more clear and common in the offl ine world. This disparity may exist because social
norms are connected to particular situations involving users (AA.VV SPION 2011 ).
In the offl ine world, more or less clear barriers exist among situations and contexts.
In this scenario, privacy is signaled by physical characteristics: e.g., low lighting,
enclosed spaces, and relative isolation from others. People who want to conduct
a private conversation can recognize the privacy levels of an offl ine space based on
physical properties (Dwyer and Hiltz 2008 ).
In the online world, missing these clear boundaries and well defi ned social norms,
and due to the fact that users have more control on how their identity is displayed
(since each user can decide which information provide to the world), often the context
is not clear and it is free to be fi lled. Online, privacy levels are not signaled by
the inherent properties of the online social space in any clear way, except for the
common assumption that nothing is private. In this scenario, some argue that privacy
in online communities should be a system level requirement, rather than a group of
access settings for each member: privacy should apply to an online space and not be
a collection of settings attached to each individual member (Dwyer and Hiltz 2008 ).