Connected vehicle means providing different services, such as advanced driver-assistance systems (ADAS) from vehicles connected to the network. Vehicular ad-hoc networks (VANETs) can support vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications to realize connected vehicle. In VANETs, secure communication must be ensured, as otherwise it can lead to traffic accidents and human injuries. Recently, many studies on V2I authentication have been conducted to guarantee the security of V2I communications. However, recent V2I authentication protocols do not consider the handover situation, and it causes unnecessary computations. As vehicles have limited computing resources, unnecessary computation can lead to overload to the vehicles. In recent years, blockchain-based VANET is an active field of research because it can provide decentralization, data integrity and transparency. Using the strength of the blockchain technology, we design a blockchain-based handover authentication protocol for VANETs. In the proposed protocol, vehicles only perform lightweight computations in handover situations for efficiency of the network. We also conduct the formal analysis such as Burrows–Abadi–Needham (BAN) logic, Real-Or-Random (ROR) oracle model, and Automated Validation of Internet Security Protocols and Applications (AVISPA) simulation to the proposed protocol. We simulate the proposed protocol using network simulator 3 (NS-3) to verify that the proposed protocol is practical. Finally, we compare the computational cost and security features of the proposed protocol with existing protocols to show that the proposed protocol is more secure and efficient.

During the COVID-19 pandemic, engagement in various remote activities such as online education and meetings has increased. However, since the conventional online environments typically provide simple streaming services using cameras and microphones, there have limitations in terms of physical expression and experiencing real-world activities such as cultural and economic activities. Recently, metaverse environments, three-dimensional virtual reality that use avatars, have attracted increasing attention as a means to solve these problems. Thus, many metaverse platforms such as Roblox, Minecraft, and Fortnite have been emerging to provide various services to users. However, such metaverse environments are potentially vulnerable to various security threats because the users and platform servers communicate through public channels. In addition, sensitive user data such as identity, password, and biometric information are managed by each platform server. In this paper, we design a system model that can guarantee secure communication and transparently manage user identification data in metaverse environments using blockchain technology. We also propose a mutual authentication scheme using biometric information and Elliptic Curve Cryptography (ECC) to provide secure communication between users and platform servers and secure avatar interactions between avatars and avatars. To demonstrate the security of the proposed mutual authentication scheme, we perform informal security analysis, Burrows–Abadi–Needham (BAN) logic, Real-or-Random (ROR) model, and Automated Validation of Internet Security Protocols and Applications (AVISPA). In addition, we compare the computation costs, communication costs, and security features of the proposed scheme with existing schemes in similar environments. The results demonstrate that the proposed scheme has lower computation and communication costs and can provide a wider range of security features than existing schemes. Thus, our proposed scheme can be used to provide secure metaverse environments.

In the recent COVID-19 situation, Telecare Medical Information System (TMIS) is attracting attention. TMIS is one of the technologies used in Wireless Body Area Network (WBAN) and can provide patients with a variety of remote healthcare services. In TMIS environments, sensitive data of patients are communicated via an open channel. An adversary may attempt various security attacks including impersonation, replay, and forgery attacks. Therefore, numberous authentication schemes have been suggested to provide secure communication for TMIS. Sahoo et al. proposed a mutual authentication scheme based on biometrics and Elliptic Curve Cryptography (ECC) in 2020. However, we find out that Sahoo et al. ’s scheme cannot resist insider and privileged insider attacks and cannot guarantee patient anonymity. In this paper, we propose a secure ECC-based three-factor mutual authentication protocol that guarantees the privacy of patients for TMIS. We conduct informal security analysis to prove that our protocol is secure from various security attacks. In addition, we perform formal security analyses using the Automated Validation of Internet Security Protocols and Applications (AVISPA), Burrows-Abadi-Needham (BAN) logic, and the Real-Or-Random (ROR) model. Furthermore, we assess our protocol’s performance and compare it to other protocols. As a result, our protocol has lower communication costs, and better security features compared to related existing protocols. Therefore, our protocol is more appropriate for TMIS environments than other related protocols.

In the traditional electronic health record (EHR) management system, each medical service center manages their own health records, respectively, which are difficult to share on the different medical platforms. Recently, blockchain technology is one of the popular alternatives to enable medical service centers based on different platforms to share EHRs. However, it is hard to store whole EHR data in blockchain because of the size and the price of blockchain. To resolve this problem, cloud computing is considered as a promising solution. Cloud computing offers advantageous properties such as storage availability and scalability. Unfortunately, the EHR system with cloud computing can be vulnerable to various attacks because the sensitive data is sent over a public channel. We propose the secure protocol for cloud-assisted EHR system using blockchain. In the proposed scheme, blockchain technology is used to provide data integrity and access control using log transactions and the cloud server stores and manages the patient’s EHRs to provide secure storage resources. We use an elliptic curve cryptosystems (ECC) to provide secure health data sharing with cloud computing. We demonstrate that the proposed EHR system can prevent various attacks by using informal security analysis and automated validation of internet security protocols and applications (AVISPA) simulation. Furthermore, we prove that the proposed EHR system provides secure mutual authentication using BAN logic analysis. We then compare the computation overhead, communication overhead, and security properties with existing schemes. Consequently, the proposed EHR system is suitable for the practical healthcare system considering security and efficiency.

Secure communication is a significant issue in wireless sensor networks. User authentication and key agreement are essential for providing a secure system, especially in user-oriented mobile services. It is also necessary to protect the identity of each individual in wireless environments to avoid personal privacy concerns. Many authentication and key agreement schemes utilize a smart card in addition to a password to support security functionalities. However, these schemes often fail to provide security along with privacy. In 2015, Chang et al. analyzed the security vulnerabilities of previous schemes and presented the two-factor authentication scheme that provided user privacy by using dynamic identities. However, when we cryptanalyzed Chang et al.’s scheme, we found that it does not provide sufficient security for wireless sensor networks and fails to provide accurate password updates. This paper proposes a security-enhanced authentication and key agreement scheme to overcome these security weaknesses using biometric information and an elliptic curve cryptosystem. We analyze the security of the proposed scheme against various attacks and check its viability in the mobile environment.

With the significant development of the Internet, Internet of Things (IoT) has become an emerging technology in many industries. To support security and privacy in the Industrial IoT environment, a user may interact with another user on the Internet to share confidential information, which requires an authenticated communication channel. To meet this demand, in this article the authors developed an identity-based two-party authenticated key agreement (ID-2PAKA) protocol that allows two users to communicate securely and share sensitive data across IoT-enabled regions. Similar protocols found in the literature either proven to be insecure or carry the burden of high communication and computational costs. The proposed ID-2PAKA protocol is analyzed in the random oracle model to achieve provable security based on the hardness assumptions of computational Diffie-Hellman and bilinear Diffie-Hellman problems. The performance analysis of the proposed ID-2PAKA protocol is performed using the pairing-based cryptography library. The comparative results from the perspective of the computation and communication costs against the competing protocols showed that the proposed ID-2PAKA protocol is secure and efficient.