Cost-effective privacy-preserving vehicular urban sensing system

Vehicular urban sensor network is a new network paradigm for sensing data collection in urban environment. An on-board unit (OBU) is required to transfer data collected from sensors to the back-end server through various wireless networks, such as DSRC/WAVE, cellular networks, WiMAX, and WLAN/Wi-Fi. However, in any of such deployment, OBU should be equipped with an expensive transmitter. After transmitted to the server, those data can be further processed for many applications, such as automated traffic enforcement, Pay-as-You-Drive insurance, electronic toll pricing, and traffic statistics. Such raw data always contains vehicle and driver's private information. Considering both cost and privacy concerns, we propose a new vehicle urban sensing infrastructure. Instead of deploying an expensive transmitter on OBU, we choose to use smartphone to transfer data through cellular network, which can be communicated with OBU equipped with a cheaper Bluetooth transmitter. To achieve privacy, we design an efficient protocol among OBU, smartphone, and back-end server by using some cryptographic techniques. Compare with the traditional OBU with 3G module (231 USD), the OBU we use is much cheaper (44.6 USD). Our protocol is also efficient enough to be deployed in practice.