Researchers Erik Karger, Marvin Jagals, and Frederik Ahlemann from the University of Duisburg-Essen, Essen, Germany, published an article in Sustainability on November 30, 2021, regarding blockchain for smart mobility. The article provides an a-up to date review on this issue. Here there are some of the key issues.
Today’s cities face numerous challenges due to climate change and urbanization. The concept of a smart city aims to help cities to address these challenges by adapting modern information and communication technology. Smart mobility and transportation form one important aspect of smart cities. Inefficient mobility in cities can lead to problems such as traffic congestion, which results in frustration for residents and a decrease in the quality of life. The major environmental and global warming impact of cities makes it necessary to act in environmentally friendly and sustainable ways. The concept of transforming urban areas into so-called smart cities arose to address the fundamental economic and ecological issues of the 21st century. Smart mobility aims to assist cities in reducing traffic, accident rates, and urban footprint. Furthermore, smart mobility concepts can help to improve air quality and thus assist cities in achieving sustainable growth, since mobility and transportation are major drivers of climate change.
New technologies like blockchain are developing rapidly. Research on smart cities and blockchain already pointed out the enormous potential of blockchain in the context of smart mobility. The study underlines that due to the blockchain’s decentralization, transparency, and immutability it is a fitting technology for deploying a decentralized trust management system in automotive networks.
Additionally, the authors stress that the blockchain has the potential to enable decentralized intelligent transportation systems and decentralized vehicular applications. The use-cases dealing with blockchain in the context of smart mobilities can be divided into five categories.
1 – Intelligent Transportation Systems
Intelligent transportation systems (ITS) have emerged with the goal to apply several advantages to mobility, like improving travel security and increasing the performance of transportation systems. In addition, ITS enables smart vehicles to communicate with each other and access the internet. Some authors take a broader perspective and propose a blockchain-based ITS model. They believe that the advantages of blockchain models like decentralization, security, and trust make it highly suitable for such a purpose.
Vehicular networks, also referred to as vehicular ad-hoc networks (VANETs), are a component of an ITS and can be defined as a self-organized network in that vehicles can communicate with each other (vehicle-to-vehicle, V2V) and with the infrastructure (vehicle to-Infrastructure, V2I). Such a VANET allows vehicles to share information about weather conditions or road defects, for example, thus increasing the security and efficiency of the traffic. With wireless communication devices on-board units (OBUs), the autonomous vehicles can communicate with each other and road side units (RSUs). A trusted authority (TA) is another component responsible for managing the whole system. However, to guarantee secure communication, several issues concerning privacy and security need to be addressed. Security in VANETs is crucial, as attacks might directly involve or endanger human lives. Here, for example, blockchain can help users obtain the trust values of other participants and received messages, or enable secure key management between different vehicles.
2 – Vehicular Communication
Next to the fundamental architecture of VANETs and ITSs, vehicular communication is another aspect in the context of smart mobility where the blockchain might be able to bring improvement. Some authors argue that, despite developments over the last years, VCSs still have to deal with problems and issues concerning security and key management. Therefore, these authors propose a blockchain-based key-management scheme to share the keys for communication between different devices or vehicles securely.
With the help of the blockchain-based approach, network participants can obtain the trust values of other participants in the network and, based on this, evaluate the trustworthiness of received messages.
3- Electric Charging
A blockchain in combination with smart contracts could be a good technology to avoid the involvement of a third party and, thus, to create the autonomy and dynamism of the approach. The study points out a solution called PETCON, which makes it possible for Plug-in Hybrid Electric Vehicles (PHEVs) to buy and sell energy from and to each other in smart grids. This enables the charging and discharging of PHEVs by simultaneously ensuring security and transparency without the need for a trusted third party.
4 – Ridesharing
Blockchain promises multiple advantages and benefits for ridesharing. Increased security is one that is mentioned most often. Security is a broad term and has many different meanings in the context of ridesharing. In most cases, though, it means security against malicious drivers and riders.
In the context of ridesharing blockchain is supposed to solve different security-related problems. Furthermore, vehicles participating in ridesharing platforms must share private in formation which is stored in a centralized and controlling instance. This centralization presents the issue of possible data leakages that threaten individual privacy. The researchers indicate that due to its decentralized nature, blockchain may be a possible answer to these security issues, since it avoids a single point of failure.
5 – Platooning
Finally, there are use-cases utilizing blockchain in the context of truck platooning. A truck platoon can be defined as a group of self-driving trucks moving together in a convoy. Truck platooning presents many advantages, including cost savings due to reduced fuel consumption, and the resultant reduced emissions. In addition, truck platoons enable more efficient use of the infrastructure by taking up less road space, which reduces the risk of traffic congestion, and increases possible traffic. Future research should address the question of which consensus algorithm is most suitable for a blockchain in the platooning context.
Malicious vehicles that can compromise the security of a platoon post a major threat to platoon configurations. This can happen, for example, through targeted cyberattacks or denial and misappropriation of payments. The study emphasises that the blockchain can help to increase the security of platoons in various ways, for instance, by allowing vehicles to validate each other’s integrity or by using smart contracts that force malicious platoon members to pay a fee. Even though blockchain is supposed to promise more security for mobility, it can also contribute to new security problems. As mentioned in the previous section, faulty smart contracts, especially, can lead to serious security issues. Thus, for blockchains to be effective in increasing security and not lead to new problems, the issue of security must also play an important role in the development of blockchain solutions for smart mobility.
Due to the increasing urban population, today’s cities are confronted with several challenges. Smart cities try to find new solutions for today’s challenges caused by urbanization and environmental change. Mobility and transportation form one crucial aspect of today’s cities. Efficient and sustainable mobility is a precondition to avoid problems like traffic congestion, to ensure a high quality of life for a city’s residents and tourists, and to reduce carbon emissions and environmental pollution.
The use of blockchain for smart mobility use-cases has already been addressed by research. However, despite the initial work in this area, the research is still fragmented and sometimes barely sufficiently integrated. With this review, the authors aim at closing this gap and providing an overview of the current state of the art in blockchain for smart mobility. They did so by categorizing the applications of blockchain for smart mobility into five different use-cases.
This can serve as a foundation for future research endeavors within this promising and emerging field. The researchers assumed that there will be a variety of future developments in the field of blockchain.