Enabling Seamless Data Security, Consensus, and Trading in Vehicular Networks

TL;DR

The paper tackles data security, consensus, and trading in vehicular networks by introducing VEE, an applicational extension that augments ITS messages with modular components (Ledger, Consensus, Token) managed by VEP. It provides a generalized framework compatible with ETSI ITS (and IEEE WAVE) that can operate in interactive or passive modes to minimize overhead while enabling secure data recording, non-safety-critical consensus, and local token-based trading. The Maneuver SP, View SP, and Tolling SP illustrate practical applications, supported by hardware-in-the-loop experiments that quantify overheads, delays, and channel load across scenarios. The findings demonstrate that VEE can deliver lightweight enhancements with acceptable performance penalties, while offering extensibility through modular sub-protocols and potential for future improvements in DLT choices, consensus strategies, and privacy-preserving mechanisms. Overall, VEE represents a scalable path toward verifiable cooperation and monetized services in decentralized vehicular ecosystems.

Abstract

Cooperative driving is an emerging paradigm to enhance the safety and efficiency of autonomous vehicles. To ensure successful cooperation, road users must reach a consensus for making collective decisions, while recording vehicular data to analyze and address failures related to such agreements. This data has the potential to provide valuable insights into various vehicular events, while also potentially improving accountability measures. Furthermore, vehicles may benefit from the ability to negotiate and trade services among themselves, adding value to the cooperative driving framework. However, the majority of proposed systems aiming to ensure data security, consensus, or service trading, lack efficient and thoroughly validated mechanisms that consider the distinctive characteristics of vehicular networks. These limitations are amplified by a dependency on the centralized support provided by the infrastructure. Furthermore, corresponding mechanisms must diligently address security concerns, especially regarding potential malicious or misbehaving nodes, while also considering inherent constraints of the wireless medium. We introduce the Verifiable Event Extension (VEE), an applicational extension designed for Intelligent Transportation System (ITS) messages. The VEE operates seamlessly with any existing standardized vehicular communications protocol, addressing crucial aspects of data security, consensus, and trading with minimal overhead. To achieve this, we employ blockchain techniques, Byzantine fault tolerance (BFT) consensus protocols, and cryptocurrency-based mechanics. To assess our proposal's feasibility and lightweight nature, we employed a hardware-in-the-loop setup for analysis. Experimental results demonstrate the viability and efficiency of the VEE extension in overcoming the challenges posed by the distributed and opportunistic nature of wireless vehicular communications.

Figures (18)

• Figure 1: ETSI ITS protocol stack with the Verifiable Event Protocol (VEP).
• Figure 2: PDU of an ETSI ITS message extended with VEE. The header sizes of each PDU component are shown. For the GeoNetworking (GN) header, ITS messages, and VEE, only the minimum sizes are shown since these have variable sizes. For these, the typical sizes are also shown, however these values can vary a lot according to several factors such as security parameters (GN), message type (ITS message), and current vehicular event type (VEE).
• Figure 3: A representation of the VEE ASN.1 message format. A full bar represents a SEQUENCE field, a dented bar represents a CHOICE field, and a dashed bar represents an OPTIONAL field.
• Figure 4: Representation of the message handling process in VEP. Possible paths of ITS messages as the protocol handles them are shown. (a) Not all received messages are deemed important by the protocol. (b) Some messages are handled by multiple SPs. In this case this DENM message triggers SP$_m$ to create a passive operation process, adding a VEE to the queue, while SP$_1$ simply saves it. (c) A queued VEE is added to a message that could potentially be extended. (d) Some messages are extended using the interactive operation mode, spending no time in the queue. (e) VsE data can be composed of several messages, extended or not.
• Figure 5: UP traffic and VEE queue delay representation.

Theorems & Definitions (4)

• Theorem 1: Safety preservation
• proof
• Theorem 2: Liveness preservation
• proof