Longitude: Centralized Privacy-Preserving Computation of Users' Proximity

A “friend finder” is a Location Based Service (LBS) that informs users about the presence of participants in a geographical area. In particular, one of the functionalities of this kind of application, reveals the users that are in proximity. Several implementations of the friend finder service already exist but, to the best of our knowledge, none of them provides a satisfactory technique to protect users’ privacy. While several techniques have been proposed to protect users’ privacy for other types of spatial queries, these techniques are not appropriate for range queries over moving objects, like those used in friend finders. Solutions based on cryptography in decentralized architectures have been proposed, but we show that a centralized service has several advantages in terms of communication costs, in addition to support current business models. In this paper, we propose a privacy-aware centralized solution based on an efficient three-party secure computation protocol, na...

• Type: Conference
• Year: 2009
• Where: SDMW
• Authors: Sergio Mascetti, Claudio Bettini, Dario Freni
• Keywords: Friend finder Service, Friend finders, Location Based Service, SDMW 2009