Towards Greater Respect for the Users Privacy in communication technologies.

Abstract

Wireless Local Area Networks (WLANs) are an emerging technology that have become increasingly popular in several locations such as businesses, educational institutions, Internet cafes, airports, etc. Since the first time WLANs appeared, users were able to communicate and exchange information and data from anywhere, access cloud services anytime, regardless of their geographic position or time. Due to their importance, WLANs which have been popular by the WiFi technology, are becoming more and more vulnerable to attacks and threats from other parties, where attackers can retrieve important data by capturing transmitted packets through access points, in which they can extract the MAC address of the transmitter, and thus be able to record the movements of the transmitter over time even when the system uses encryption as layer 2 headers, particularly the MAC address which uniquely identifies a mobile station is not encrypted. Existing solutions to this privacy breach aim at using pseudonyms to avoid using the same MAC address and also introduce silent periods to make it difficult for an attacker to track users. Due to the downside of the existing solutions, in this thesis we propose two contributions, the first contribution consists of a mathematical model to quantify the privacy and a decentralized algorithm that use silent periods (SPs) to change the MAC address, and allow users to attain their desired levels of privacy while lowering its effect on the QoS perceived by them. The introduction of silent periods may have negative effects on some applications particularly for those with iAbstract constraints on bandwidth and delay such as video streaming. Therefore, in our second contribution, we propose an enhanced silent-period-based solution that allows to maximize the perceived QoS for a preset privacy. Our solutions offer users the best trade-off between privacy and QoS. We experimented our proposal with a set of numerical simulations. The obtained results demonstrated the efficiency of the proposed solution.