Virtual trip lines for distributed privacy-preserving traffic monitoring

Abstract

Automotive traffic monitoring using probe vehicles with Global Positioning System receivers promises significant improvements in cost, coverage, and accuracy. Current approaches, however, raise privacy concerns because they require participants to reveal their positions to an external traffic monitoring server. To address this challenge, we propose a system based on virtual trip lines and an associated cloaking technique. Virtual trip lines are geographic markers that indicate where vehicles should provide location updates. These markers can be placed to avoid particularly privacy sensitive locations. They also allow aggregating and cloaking several location updates based on trip line identifiers, without knowing the actual geographic locations of these trip lines. Thus they facilitate the design of a distributed architecture, where no single entity has a complete knowledge of probe identities and fine-grained location information. We have implemented the system with GPS smartphone clients and conducted a controlled experiment with 20 phone-equipped drivers circling a highway segment. Results show that even with this low number of probe vehicles, travel time estimates can be provided with less than 15% error, and applying the cloaking techniques reduces travel time estimation accuracy by less than 5% compared to a standard periodic sampling approach.

Smart City Governance: A Local Emergent Perspective

“…Traffic monitoring systems, for example, with cameras and sensors can provide city governments with precise information about traffic streams and congestions, and these governments can use this information for traffic management (Hoh et al 2008). In addition, technologies for communication in policy networks and communities can bring together a wide variety of urban actors to generate more distributed urban intelligence (Lathrop and Ruma 2010;Linders 2012;Nijkamp and Kourtit 2013).…”

An efficient algorithm for detecting traffic congestion and a framework for smart traffic control system

“…Cell phone towers creates a mesh network and for that a ordinary phone can be tracked easily by using that advantages [21], [22] in these ordinary phone they have shown a simple sensor can be incorporated. [23], [24] these research shows the "crowed sourcing" is a great way sense traffic by the signals, though it has some privacy issues [25], [26], [27], [28] An Efficient Algorithm for Detecting Traffic Congestion and a Framework for Smart Traffic Control System Page | 14 Thus these system were never publicized nor accepted by the people or the users.…”

The changing role of pervasive middleware: From discovery and orchestration to recommendation and planning

“…The issue of enforcing privacy in e-mobility system has been extensively faced, and some solutions are available. [Hoh08], for instance, introduces the concept of virtual trip lines (geographical markers that triggers the cars' location update) to mediate interactions between vehicles. Yet, more general solutions are to be investigated to support all the intricacies of the scenario.…”