AdaptAnon: Adaptive anonymity for service queries in mobile opportunistic networks

Social routing protocols are typically used to transfer messages among users and services in mobile opportunistic networks. Adaptive mechanisms are needed for achieving user anonymization and providing sufficient level of user anonymity due to the constant changes in underlying topology, mobility patterns and density of users and their queries. This paper describes a novel flexible and adaptive approach, AdaptAnon that is suitable for dynamic and heterogeneous mobile opportunistic networks. Our approach is multidimensional and combines multiple heuristics based on user profiles, analysis of user connectivity and history of anonymization in order to predict and decide on the best set of nodes that anonymize the sending node. Our results of extensive experiments show that AdaptAnon achieves higher quality of anonymization in terms of both the number of nodes and the diversity of nodes in the anonymization layer for varying query intensity and over different sender and destination degrees of connectivity while neither decreasing success ratios nor increasing latency. We show that AdaptAnon outperforms state of the art single dimensional anonymization approaches when run over three different real-life traces.