Providing Mobile Users' Anonymity in Hybrid Networks
The authors present a novel hybrid communication protocol that guarantees mobile users' k-anonymity against a wide-range of adversaries by exploiting the capability of handheld devices to connect to both WiFi and cellular networks. Unlike existing anonymity schemes, they consider all parties that can intercept communications between the mobile user and a server as potential privacy threats. They formally quantify the privacy exposure and the protection of their system in the presence of malicious neighboring peers, global WiFi eavesdroppers, and omniscient mobile network operators. They show how their system provides an automatic incentive for users to collaborate, since by forwarding packets for other peers users gain anonymity for their own traffic.