SmokeScreen: flexible privacy controls for presence-sharing

Presence-sharing is an emerging platform for mobile applications, but presence-privacy remains a challenge. Privacy controls must be flexible enough to allow sharing between both trusted social relations and untrusted strangers. In this paper, we present a system called SmokeScreen that provides flexible and power-efficient mechanisms for privacy management. Broadcasting clique signals, which can only be interpreted by other trusted users, enables sharing between social relations; broadcasting opaque identifiers (OIDs), which can only be resolved to an identity by a trusted broker, enables sharing between strangers. Computing these messages is power-efficient since they can be precomputed with acceptable storage costs. In evaluating these mechanisms we first analyzed traces from an actual presence-sharing application. Four months of traces provide evidence of anonymous snooping, even among trusted users. We have also implemented our mechanisms on two devices and found the power demand...

• Type: Conference
• Year: 2007
• Where: MOBISYS
• Authors: Landon P. Cox, Angela Dalton, Varun Marupadi
• Keywords: Clique Signals, Keywords Location Privacy, MOBISYS 2007, Trusted Users, Wireless Networks