Lightweight and Privacy-Preserving Access Protocols for Low Emission Zones

Identifier:  TDX:3316

Handle: https://hdl.handle.net/20.500.11797/TDX3316

Authors:  Anglés Tafalla, Carles

Abstract:
In the last years, Low Emission Zones (LEZ), i.e. areas where some restrictions and surcharges are applied to polluting vehicles, have emerged as one of the most popular mechanisms to tackle urban traffic congestion and environmental pollution. The rapid proliferation of LEZs through all Europe is clear example of this increasing trend. Even though LEZs have proven to be an effective measure against those issues, they have also been criticized in the literature due to the relevant privacy threat that they pose to the drivers passing by. In particular, current deployed systems used to enforce LEZs strongly depend on the indiscriminate use of camera networks to track the drivers' whereabouts, requiring infrastructures that can hinder their deployment in real scenarios. Moreover, these solutions also reveal a strong dependence on centralized entities to manage the vehicles' access acknowledgment, fare ascertaining and fee payment. The inherent reliance on those entities poses a single point of failure, jeopardizing the system's security and stability. The aim of this thesis is to contribute with novel privacy-preserving protocols for LEZ Access Control schemes which tackle the deployability and centralization issues found in the current literature works, while providing effective anti-fraud measures to preserve the privacy of the drivers who behave honestly. Under these premises, in the first contribution, we propose an access control system for LEZs lightweight enough to be used in low-cost infrastructures, whose cornerstone is its deployability in real scenarios. Regarding our second and third contributions, two access control protocols for LEZs are proposed in order to shed the centralized position that third parties, responsible of registering vehicle accesses and charging fees, hold in favor of the blockchain decentralized paradigm. The privacy-preserving mechanisms used in those works address the user's privacy requirements that a public ledger like blockchain demands.