How to Demonstrate Our Presence without Disclosing Identity? Evidence from a Grouping-Proof Protocol SPEAKER Mr ZHUANG Yun Hui PhD Student Department of Computer Science City University of Hong Kong Hong Kong DATE 24 August 2015 (Monday) TIME 4:30 pm - 5:00 pm VENUE CS Seminar Room, Y6405, 6th Floor Yellow Zone, Academic 1 City University of Hong Kong 83 Tat Chee Avenue Kowloon Tong ABSTRACT The recent hot debate on "mobile sharing economy" has been an emergence in a dynamic ownership economy, which attracts lots of attentions in the news media. The concept and practice of resource sharing has been fast becoming a mainstream phenomenon across the world. People share assets to their friends via Internet or smartphones. Meanwhile, researchers are now beginning to weigh in with deeper analysis in terms of security and privacy, which turn out to be one critical area of argument when sharing the items with others. To securely track the location of the item is of high importance in many mobile applications, which rely heavily on the notion of device proximity. In addition to securely and precisely determining an item's location, it is also desirable to preserve the privacy and untraceability of the item. Grouping-proof protocols are often used to prove the presence of a group of Provers to the Verifier at the same time. In this paper, we propose a new grouping-proof protocol that is well deployed in proximity identification systems, where each Prover needs to demonstrate its presence to the Verifier without disclosing its real identity. Our protocol is mutually authenticated and secure against all known attacks in a grouping-proof setting. Furthermore, the protocol retains the untraceability of a tag through forward privacy and prevents de-synchronization attacks. This paper will be presented at The 16th International Workshop on Information Security Applications (WISA 2015), Jeju Island, Korea, August 20-22, 2015 Supervisor: Dr Gerhard P Hancke Research Interests: Information and System Security; RFID, Smart Cards/Tokens and IoT; Sensing and Control Systems; Embedded Systems All are welcome! In case of questions, please contact Dr Gerhard P Hancke at Tel: 3442 9341, E-mail: gp.hancke@cityu.edu.hk, or visit the CS Departmental Seminar Web at http://www.cs.cityu.edu.hk/.