On Enhancing Location Privacy and QoS for Video Streaming Over Wireless Networks

In wireless networks based on the IEEE 802.11 standard, mobile stations communicate with access points through the exchange of packets transmitted over the air. These packets can be captured by any listener in the vicinity which 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. The introduction of silent periods may have negative effects on some applications particularly for those with constraints on bandwidth and delay such as video streaming. In this paper, we propose an enhanced silent period-based solution that allows to maximize the perceived QoS for a preset privacy. Our solution is elaborated from our mathematical model that allows to: (i) quantify the desired user location privacy and QoS, (ii) compute the silent and active periods that cope with these two objectives, and (iii) 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.