  Despite the several advantages commonly attributed to social networks such as
easiness and immediacy to communicate with acquaintances and friends,
significant privacy threats provoked by unexperienced or even irresponsible
users recklessly publishing sensitive material are also noticeable. Yet, a
different, but equally hazardous privacy risk might arise from social networks
profiling the online activity of their users based on the timestamp of the
interactions between the former and the latter. In order to thwart this last
type of commonly neglected attacks, this paper presents a novel, smart deferral
mechanism for messages in online social networks. Such solution suggests
intelligently delaying certain messages posted by end users in social networks
in a way that the observed online-activity profile generated by the attacker
does not reveal any time-based sensitive information. Conducted experiments as
well as a proposed architecture implementing this approach demonstrate the
suitability and feasibility of our mechanism.
