- مبلغ: ۸۶,۰۰۰ تومان
- مبلغ: ۹۱,۰۰۰ تومان
The wide adoption of smart phones has enabled Online Social Networks (OSNs) to exploit the location awareness capabilities offering users better interaction and context aware content. While these features are very attractive, the publication of users’ location in an OSN exposes them to privacy hazards. Recently, various protocols have been proposed for private proximity testing, where users are able to check if their online friends are near, without disclosing their locations. However, the computation cost of the required cryptographic operations utilized in such protocols is not always efficient for mobile devices. In this paper we introduce a lightweight and secure proximity testing protocol, suitable for online mobile users. We show that our protocol is provably secure under the well-known factoring problem and we analyze its efficiency. Our results show that our approach outperforms other existing protocols, by significantly reducing the computational cost and making it practical for devices with limited resources. Finally, we demonstrate the applicability of our proposal in an actual OSN location-based, mobile application.
7. Discussion and comparison with related work
For a holistic evaluation of the proposed protocol against similar approaches, we summarize their similarities and differences regarding the aim, the security and the efficiency characteristics. Table 3 provides such a comparison with the protocols of [13–15,17], since all these protocols are suitable for low entropy (location) input data. While all these protocols aim at proximity testing, the original version of the NFP protocol  allows only the initiator (Alice) of the protocol to learn the proximity result, while the responder (Bob) learns nothing. All other protocols are asymmetric in the sense that Alice first learns the result and optionally can run an additional round to also let Bob learn the outcome of the proximity test. The NFP protocol could also be extended to provide asymmetry but in its current version it requires a second protocol run with Bob as the initiator.