Smart cities involve the use of smart technology and data to address sustainability problems in cities. Many cities are striving to become smart, using data and technology to improve transportation, energy usage, health, and air quality and boost economic development. Others are designed from the ground up to be smart. A smart city employs information and communication technology (ICT) to improve the quality, performance, and interactivity of urban services and decrease costs and resource consumption and improve citizen-government communication. Government services, transportation and traffic management, electricity, healthcare, water, creative urban agriculture, and waste management are all areas where smart city technology is being developed. As a result, a smart city may be more equipped to react to problems than a city with a purely transactional relationship with its people. In general, smart cities incorporate different entities that communicate daily, industrial services that allow access to other resources to enhance their capabilities of serving people. However, this technology, particularly future generation computer systems and smart devices used in smart cities, raises security and privacy threats.

Several industries have utilized blockchain technology. It has future benefits as a transformative platform for many recent and future technologies. Blockchain offers secure, transparent, and verifiable transactions with privacy, proof of rights, and ownership. It also provides a range of ways to help people and devices with increased trust, protection, and privacy mechanisms by enabling secure data transfer in smart cities. Moreover, Blockchain serves as a crucial initiative for smart city networks to open distributed identification instead of centralized smart city systems. Through blockchain-assisted smart city technologies, data flow through smart city networks is continuously tracked and processed through decentralized storage platforms. The user/software agent will then view data securely from anywhere with the highest degree of data protection and integrity measures. Private blockchain technologies can be applied to retain efficient data accountability and audibility. In addition, blockchain technology has been successfully utilized in smart city industries. Among the benefits, the current methods of blockchain-assisted smart city systems have major disadvantages, such as scalability problems, inadequate storage facilities, increased processing, and time. Therefore, the need for innovative blockchain solutions is ever-increasing, requiring a certain level of creativity and innovation.

This Special Issue aims to explore blockchain solutions development for smart city networks and data. It also aims to address different topics across multiple abstraction levels, ranging from architectural models, the provisioning of services, protocols, and interfaces to specific implementation approaches. It aims to present the most important and relevant advances to overcome the challenges related to security and effective solutions for smart city networks and effective data transfer. Original research and review articles are welcome.

Potential topics include but are not limited to the following:

• Blockchain-assisted lightweight protocol design methods for smart cities
• Advances in blockchain-assisted distributed machine learning solutions for smart environment
• Innovative methods of theoretical models and architectural designs for smart cities using blockchain techniques
• Trust-based models for smart city applications using blockchain methodologies
• Blockchain assisted fog, edge, and cloud computing models for secure smart city networks and data
• Advances in blockchain and cybersecurity for smart city applications
• Effective ways to improve performance and efficiency measures of applications with blockchain techniques
• Blockchain-assisted federated learning solutions for secure smart cities mobile applications
• Advances in vulnerability and risk management across smart cities environment with blockchain and artificial intelligence methodologies
• Blockchain for smart cities security from a future perspective
• Blockchain-based access control
• Advances in big data analytics with blockchain methodologies for secure smart cities