Boying Zhang

P 3 -coupon: A probabilistic system for Prompt and Privacy-preserving electronic coupon distribution

In this paper, we propose P3-coupon, a Prompt and Privacy-preserving electronic coupon distribution system based on a Probabilistic one-ownership forwarding algorithm. In this algorithm, only one hop of forwarder (coupon owner) information instead of the complete forwarder list is recorded to keep the coupon short and privacy-preserving. Such information is updated probabilistically following two ownership flipping models, namely, One-Flip and Always-Flip models. We also use a Bluetooth Service Discovery Protocol (SDP) toolkit to enable fast, configuration-free coupon exchange. We have implemented the system in Java ME. Our experiments on real world mobile phones, such as Nokia and Samsung phones, and large scale simulations show that our system is efficient in peer to peer coupon distribution and capable of massive deployment. We believe our key methodology can serve as a general framework for facilitating information propagation on mobile phones, which requires promptness and privacy protection.

E-V: Efficient visual surveillance with electronic footprints

Video cameras have been deployed at almost every critical location, and they keep generating huge volumes of video data. The current visual processing technologies are not efficient in handling all these data for surveillance purposes, and a large amount of human power is needed to process them. In this paper, we propose the E-V system, which uses electronic footprints to help sort through this swamp of data. Electronic footprints are wireless signals emitted by mobile devices carried by people. They are ubiquitous and amenable to collection and indexing. We study how to use electronic footprints to help quickly and accurately identify objects appearance model from large volumes of video data. We have formulated the problem and provided efficient algorithms to achieve the identification on large data sets. Real world experiments and large-scale simulations have been done, which confirms the feasibility and efficiency of the proposed algorithms.

Incentive-Driven and Privacy-Preserving Message Dissemination in Large-Scale Mobile Networks

In this paper, we propose a new type of incentive-driven and privacy-preserving systems for large-scale message dissemination in mobile networks. To distribute incentives which encourage forwarding behaviors, such as monetary rewards, we want to keep track of the forwarder list. In our algorithms, we rely on a Probabilistic one-ownership forwarding algorithm to record the list, so that the exchanged messages can be kept short and privacy preserving. More specifically, only one hop of forwarder information, instead of the complete list, is recorded, and the information is updated probabilistically following two ownership flipping models, namely, One-Flip and Always-Flip models. We also use a Bluetooth Service Discovery Protocol (SDP) toolkit to enable fast, configuration-free message exchange. Throughout the paper, we use coupon as a typical type of message to illustrate the core ideas. We have implemented the coupon dissemination system in Java ME. Our experiments on real-world mobile phones, such as Nokia and Samsung phones, and large-scale simulations show that our system is efficient in peer-to-peer message distribution and capable of massive deployment. We believe our key methodology can serve as a general framework for facilitating information propagation on mobile phones, where incentives and privacy protection are both essential.

D-Card: A distributed mobile phone based system for relaying verified friendships

Cyber-physical networking systems (CPNSs) closely bridge cyberspace and the physical world. Cyberspace includes not only the Internet, but also telephone networks and short-range communications. CPNSs arise in many application domains, including social networking. Social CPNSs connect people embodied in the physical world with cyber social networking services to facilitate social interactions, including friendship formation. These services can be characterized by their dependence on Internet connections to operate. An important class of social CPNSs are mobile phone based ones. However, there is a lack of friendship verification in mobile phone based social CPNSs that allow miscreants to masquerade as friends. In this paper, we present D-Card, a mobile phone based social CPNS that provides friendship verification. D-Card provides an electronic name card that encodes relationship information for a person with his contact information. The name card includes a public key and digital signature. Comparing this public key with one from a trusted source enables identity verification. D-Card leverages a Bluetooth SDP toolkit to exchange information without requiring connection establishment. D-Card is a purely distributed CPNS that requires no Internet access or infrastructure. We implement the D-Card CPNS in Java ME and Bluetooth. Our experiments with real-world mobile phones illustrate its potential for friendship verification in mobile phone based social CPNSs. To the best of our knowledge, D-Card is the first such CPNS designed for this purpose.

MPSL: A Mobile Phone-Based Physical-Social Location Verification System

In this paper, we introduce a new concept, Physical-Social Location (PSL), and propose MPSL, a mobile phone-based system to verify users’ self-report location claims for mobile social network service (MSNS). Unlike instant discrete location points, PSLs are geographic regions obtained over longer timescales and center around regularly visited locations of social significance, e.g., workplaces or neighborhoods. PSL verification can prevent the user from reporting fake locations, e.g. GPS coordinate, trajectory or geographic profile, to location-sensitive applications as well as aid online credibility in MSNS. In our MPSL system, a user’s location claim is proved by a set of selective co-located people serving as ”witnesses”. It is composed of two parts, i.e., proof generation and verification. The former leverages a certain number of co-located people to generate co-location certificates as location proofs during their physical encounters via Bluetooth. An efficient verification scheme is proposed to make our system accurate and adaptive. Besides, incentive are taken into account to keep our distributed system applicable. We have implemented the MPSL system using real-world Nokia N82 phones. Our experimental results show that our mobile phone based system can achieve high verification accuracy and good privacy protection.