Location sharing with secrecy guarantees in mobile social networks: Unterschied zwischen den Versionen

Aktuelle Version vom 5. November 2019, 18:19 Uhr

Vortragende(r)	Yifan Bao
Vortragstyp	Masterarbeit
Betreuer(in)	Gabriela Suntaxi
Termin	Fr 8. November 2019
Vortragsmodus
Kurzfassung	With the increasing popularity of location-based services and mobile online social networks (mOSNs), secrecy concerns have become one of the main worries of its users due to location information exposure. Users are required to store their location, i.e., physical position, and the relationships that they have with other users, e.g., friends, to have access to the services offered by these networks. This information, however, is sensitive and has to be protected from unauthorized access. In this thesis, we aim to offer location-based services to users of mOSNs while guaranteeing that an adversary, including the service provider, will not be able to learn the locations of the users (location secrecy) and the relationship existing between them (relationship secrecy). We consider both linking attacks and collusion attacks. We propose two approaches R-mobishare and V-mobishare, which combine existing cryptographic techniques. Both approaches use, among others, private broadcast encryption and homomorphic encryption. Private broadcast encryption is used to protect the relationships existing between users, and homomorphic encryption is used to protect the location of the users. Our system allows users to query their nearby friends. Next, we prove that our proposed approaches fulfill our secrecy guarantees, i.e., location and relationship secrecy. Finally, we evaluate the query performance of our proposed approaches and use real online social networks to compare their performance. The result of our experiments shows that in a region with low population density such as suburbs, our first approach, R-mobishare, performs better than our approach V-mobishare. On the contrary, in a region with high population density such as downtown, our second approach, V-mobishare, perform better than R-mobishare.

@@ Zeile 2: / Zeile 2: @@
 |vortragender=Yifan Bao
 |email=urdzs@student.kit.edu
-|vortragstyp=Proposal
+|vortragstyp=Masterarbeit
 |betreuer=Gabriela Suntaxi
-|termin=Institutsseminar/2019-03-01
+|termin=Institutsseminar/2019-11-08 Zusatztermin
-|kurzfassung=With the increasing popularity of Location-based services and mobile social networks, secrecy concerns have become one of the main worries due to location information exposure. The challenges in Location sharing in mOSNs regarding secrecy are manifold:  1.  How to offer location secrecy guarantees?  2.  How to offer relationships secrecy guarantees?  3.  How to conduct location-dependent queries whileguaranteeing 1 and 2?
+|kurzfassung=With the increasing popularity of location-based services and mobile online social networks (mOSNs), secrecy concerns have become one of the main worries of its users due to location information exposure. Users are required to store their location, i.e., physical position, and the relationships that they have with other users, e.g., friends, to have access to the services offered by these networks. This information, however, is sensitive and has to be protected from unauthorized access.
+In this thesis, we aim to offer location-based services to users of mOSNs while guaranteeing that an adversary, including the service provider, will not be able to learn the locations of the users (location secrecy) and the relationship existing between them (relationship secrecy). We consider both linking attacks and collusion attacks. We propose two approaches R-mobishare and V-mobishare, which combine existing cryptographic techniques. Both approaches use, among others, private broadcast encryption and homomorphic encryption. Private broadcast encryption is used to protect the relationships existing between users, and homomorphic encryption is used to protect the location of the users. Our system allows users to query their nearby friends. Next, we prove that our proposed approaches fulfill our secrecy guarantees, i.e., location and relationship secrecy. Finally, we evaluate the query performance of our proposed approaches and use real online social networks to compare their performance. The result of our experiments shows that in a region with low population density such as suburbs, our first approach, R-mobishare, performs better than our approach V-mobishare. On the contrary, in a region with high population density such as downtown, our second approach, V-mobishare, perform better than R-mobishare.
-Until now, several solutions have been proposed to preserve user’s
-privacy in mOSNs. However, we consider that the protection of user’s
-privacy in these previous solutions can still be improved.  We propose
-a location sharing system achieving enhanced privacy by introducing a
-new untrusted third-party server called access control server.  We
-solve the problem of privacy-preserving location sharing by using
-broadcast encryption and Fully Homomorphic Encryption. While
-guaranteeing location secrecy and relationships secrecy, our system
-supports one type of query that users in mOSNs are interested in is
-who are my nearby Friends.
 }}