Blockchain Papers

Zisang Xu, Liang Wei, Kuan‐Ching Li, Jianbo Xu · 5 authors

No abstract is available for this record.

Ran Canetti, Rosario Gennaro, Steven Goldfeder, Nikolaos Makriyannis · 5 authors

Building on the Gennaro & Goldfeder and Lindell & Nof protocols (CCS '18), we present two threshold ECDSA protocols, for any number of signatories and any threshold, that improve as follows over the state of the art: -- For both protocols, only the last round requires knowledge of the message, and the other rounds can take place in a preprocessing stage, lending to a non-interactive threshold ECDSA protocol. -- Both protocols withstand adaptive corruption of signatories. Furthermore, they include a periodic refresh mechanism and offer full proactive security. -- Both protocols realize an ideal threshold signature functionality within the UC framework, in the global random oracle model, assuming Strong RSA, DDH, semantic security of the Paillier encryption, and a somewhat enhanced variant of existential unforgeability of ECDSA. -- Both protocols achieve accountability by identifying corrupted parties in case of failure to generate a valid signature. The two protocols are distinguished by the round-complexity and the identification process for detecting cheating parties. Namely: -- For the first protocol, signature generation takes only 4 rounds (down from the current state of the art of 8 rounds), but the identification process requires computation and communication that is quadratic in the number of parties. -- For the second protocol, the identification process requires computation and communication that is only linear in the number of parties, but signature generation takes 7 rounds. These properties (low latency, compatibility with cold-wallet architectures, proactive security, identifiable abort and composable security) make the two protocols ideal for threshold wallets for ECDSA-based cryptocurrencies.

Andrea Tesei, Domenico Lattuca, Marco Luise, Paolo Pagano · 6 authors

The widespread adoption of Cooperative, Connected, and Automated Mobility (CCAM) applications requires the implementation of stringent security mechanisms to minimize the surface of cyber attacks. Authentication is an effective process for validating user identity in vehicular networks. However, authentication alone is not enough to prevent dangerous attack situations. Existing security mechanisms are not able to promptly revoke the credentials of misbehaving vehicles, thus tolerate malicious actors to remain trusted in the system for a long time. The resulting vulnerability window allows the implementation of complex attacks, thus posing a substantial impairment to the security of the vehicular ecosystem. In this paper we propose a Distributed Ledger-based Vehicular Revocation Scheme that improves the state of the art by providing a \textit{vulnerability window} lower than 1 second, reducing well-behaved vehicles exposure to sophisticated and potentially dangerous attacks. The proposed scheme harnesses the advantages of the underlying Distributed Ledger Technology (DLT) to implement a privacy-aware revocation process while being fully transparent to all participating entities. Furthermore, it meets the critical message processing times defined by EU and US standards, thus closing a critical gap in the current international standards. Theoretical analysis and experimental validation demonstrate the effectiveness and efficiency of the proposed scheme, where DLT streamlines the revocation operation overhead and delivers an economically viable yet scalable solution against cyber attacks on vehicular systems.

Berat Yilmaz, Ertugrul Barak, Suat Özdemi̇r

WebRTC (Web Real-Time Communication) is one of the most popular technologies that provide the infrastructure for real-time data communications. Many applications used in military and civilian life depend on WebRTC technology directly or indirectly in the background. Due to its wide area of applications, the security of WebRTC communications is of great importance. In this paper, we improve the existing security infrastructure of WebRTC. The proposed solution provides a real-time communication infrastructure between peers on the network by making use of quite new and popular blockchain and smart contract technologies. Within the scope of the paper, a web-based application with video calling feature demonstrating blockchain interactions and suggested security enhancements have been developed. In the application, operations such as adding, updating, and authorizing users can be performed on the smart contract deployed on the live Ethereum network. Based on the principle of immutability of blockchains, users on the smart contract are mapped to the peers (nodes) in the WebRTC communication to be established and used in the identity verification process. Consequently, this paper proposes a secure identity verification method that could be used by real-time WebRTC communication peers to verify each other on the blockchain. The proposed solution is shown to resilient against man-in-the-middle attacks.

Victor Youdom Kemmoe, Yongseok Kwon, Seunghyeon Shin, Rasheed Hussain · 6 authors

Group Key Agreement (GKA) mechanisms play a crucial role in realizing various applications in different networks, such as sensor networks and the Internet of Things (IoT). To be suitable for IoT, a GKA must satisfy several critical requirements. First, a GKA must be robust against a compromised device attack and satisfy essential secrecy definitions without the existence of a Trusted Third Party (TTP). TTP is often used by IoT devices to establish ad hoc networks securely, and usually, these devices are resource-constrained. Second, the GKA must be able to distribute session keys successfully, even with offline devices. Third, a GKA must reduce the burden of heavy cryptographic computations for IoT devices. Based on these observations, we propose a new GKA scheme that satisfies all the requirements above. The proposed scheme leverages smart contracts to alleviate the computational and storage overheads on IoT devices induced by cryptographic functions. It also brings the advantage of asynchronism such that offline devices will be able to compute the group key once they are online.

Maliha Sultana, Afrida Hossain, Fabiha Laila, Kazi Abu Taher · 5 authors

BACKGROUND: Data security has been a critical topic of research and discussion since the onset of data sharing in e-health systems. Although digitalization of data has increased efficiency and speed, it has also made data vulnerable to cyber attacks. Medical records in particular seem to be the regular victims of hackers. Several data breach incidents throughout history have warranted the invention of security measures against these threats. Although various security procedures like firewalls, virtual private networks, encryption, etc are present, a mix of these approaches are required for maximum security in medical image and data sharing. METHODS: Relatively new, blockchain has become an effective tool for safeguarding sensitive information. However, to ensure overall protection of medical data (images), security measures have to be taken at each step, from the beginning, during and even after transmission of medical images which is ensured by zero trust security model. In this research, a number of studies that deal with these two concepts were studied and a decentralized and trustless framework was proposed by combining these two concepts for secured medical data and image transfer and storage. RESULTS: Research output suggested blockchain technology ensures data integrity by maintaining an audit trail of every transaction while zero trust principles make sure the medical data is encrypted and only authenticated users and devices interact with the network. Thus the proposed model solves a lot of vulnerabilities related to data security. CONCLUSIONS: A system to combat medical/health data vulnerabilities has been proposed. The system makes use of the immutability of blockchain, the additional security of zero trust principles, and the scalability of off chain data storage using Inter Planetary File Systems (IPFS). The adoption of this system suggests to enhance the security of medical or health data transmission.

OUYANG Hengyi, XIONG Yan, HUANG Wenchao

To address the frequent security incidents of token smart contracts,this paper proposes a formal modeling and verification method based on integer overflow vulnerabilities of token smart contracts.The DAO and BEC vulnerability attacks are analyzed,and on this basis the security attributes of token smart contracts are defined.Then the method introduces global variables,numeric comparison and other constraints to extend the modeling language of token smart contracts,so as to enable it to support the formal representation of various statements of smart contracts.Finally,the idea of mathematical induction is used to optimize the model verification procedure of the SmartVerif tool in order to avoid infinite traversal of state space.Experimental results show that the proposed method can successfully find out the integer overflow vulnerabilities of token smart contracts,and has strong versatility.

Mohammad Wazid, Basudeb Bera, Ankush Mitra, Ashok Kumar Das · 5 authors

Internet of Drones (IoD) architecture is designed to support a co-ordinated access for the airspace using the unmanned aerial vehicles (UAVs) known as drones. Recently, IoD communication environment is extremely useful for various applications in our daily activities. Artificial intelligence (AI)-enabled Internet of Things (IoT)-based drone-aided healthcare service is a specialized environment which can be used for different types of tasks, for instance, blood and urine samples collections, medicine delivery and for the delivery of other medical needs including the current pandemic of COVID-19. Due to wireless nature of communication among the deployed drones and their ground station server, several attacks (for example, replay, man-in-the-middle, impersonation and privileged-insider attacks) can be easily mounted by malicious attackers. To protect such attacks, the deployment of effective authentication, access control and key management schemes are extremely important in the IoD environment. Furthermore, combining the blockchain mechanism with deployed authentication make it more robust against various types of attacks. To mitigate such issues, we propose a private-blockchain based framework for secure communication in an IoT-enabled drone-aided healthcare environment. The blockchain-based simulation of the proposed framework has been carried out to measure its impact on various performance parameters.

S. Venkata Sai Santosh, M. Kameswara Rao, P. S. G. Aruna Sri, C. H. Sai Hemantha

No abstract is available for this record.

Guangsong Li, Yang Wang, Bin Zhang, Siqi Lu

Nowadays, it is still a major challenge to design a secure cross-domain authentication protocol for heterogeneous wireless networks with different security parameters. As a new technology, blockchain has attracted people’s attention because of its tamper-proof and decentralized characteristics. In this paper, we propose a cross-domain authentication and key agreement system based on smart contract of blockchains. Public keys of the nodes are managed using the smart contracts, and the system parameters are confirmed by contract query. On this basis, a cross-domain authentication and key agreement protocol is designed. In this protocol, roaming users can select temporary authentication parameters according to the system parameters of the roaming domain to complete authentication and key agreement, and users are anonymous in the process. Security of the protocol is demonstrated under the CK model, and two formal analysis tools are used to further analyze the protocol. Since the protocol does not have complex cryptographic operations and certificate verification, it has lower computational and communication overhead.

Pouyan Razmjouei, Abdollah Kavousi‐Fard, Morteza Dabbaghjamanesh, Tao Jin · 5 authors

For quite a long time, purchasers have come to depend on the convenience and security and included security that a passive vehicle immobilizer framework offers. These frameworks comprise of a Passive Entry Passive Start (PEPS) innovation, conveyed by the driver, and a Smart Key Unit (SKU), mounted in the vehicle with regards to the principal parts of these frameworks. This paper for the first time shows the cyber vulnerability of PEPS in the vehicle against the man-in-the middle attack (MITM). It enables the hacker to open and begin the vehicle, although there was still a distance between the vehicle and the key. To stop this physical cyber attack, we propose a hearty ultra-lightweight common confirmation technique dependent on the radio frequency identification (RFID) convention that cooperates with a decentralized database to verify the PEPS. A secure blockchain based on smart contract is also developed which is compatible with the mutual authentication in the vehicle. A detailed security analysis is performed on an undefined vehicle to prove the high security of the proposed communication approach when facing MITM.

Jianbo Xu, Xiangwei Meng, Wei Liang, Hongbo Zhou · 5 authors

Wireless Body Area Networks (WBANs) refer to small sensor network that consists of sensor devices mounted on the surface of the body or implanted in the body, as such networks are employed to harvest physiological data of the human body or to act as an assistant regulator of several specific physiological indicators of the human body. The sensor devices transmit the harvested human physiological data to the local node via a public channel. Before transmitting data, the sensor device and the local node should perform mutual authentication and key agreement. It is proposed in this paper a secure mutual authentication scheme of blockchain-based in WBANs. To analyze the security of this scheme, formal security analysis, and informal security analysis are used, then the computation and communication costs are compared with those of the relevant schemes. Relevant experimental results reveal that the proposed scheme exhibit more effective control over energy consumption and promising.

V. Lakshman Narayana, Divya Midhunchakkaravarthy

Mobile Ad hoc Networks (MANETs) are non-fixed framework systems and there are such a large number of issues with them because of their dynamic topology, portable nodes, security, data transfer capacity, restricted battery strength and so forth. Trust is an association, dependability, unwavering excellence, and loyalty of the nodes in the system. A trusted routing plan is essential to guarantee the routing security and productivity of sensor systems. In perspective on these issues, this manuscript proposes a trusted routing plan utilizing block chain and building up a security model to improve the routing security and productivity for ad hoc networks. The possible routing plan is given for acquiring routing data of routing nodes on the block chain, which makes the routing data distinct and difficult to alter. The support learning model is utilized to help routing nodes progressively select increasingly trusted and productive routing connections. The proposed work introduces a Trust Based Efficient Blockchain Linked Routing Method (TbEBCLRM) for a system of trusted and untrusted nodes. The proposed method utilizes blockchain method to improve security in the ad hoc networks and to avoid malicious activities during communication is initiated. The proposed method is compared with the traditional methods and the results show that the proposed method exhibits better performance in terms of accuracy, security level, trust level and energy consumption.

Jan Kotráš

Tato diplomová práce se zabývá technologii blockchain se zaměřením na konsenzus protokoly, zvláště protokoly typu proof-of-stake. V této práci naleznete popis těchto protokolů následovaný popisem konsenzu v technologii blockchain. Prvotní kapitoly detailněji popisují a porovnávají jednotlivé proof-of-stake protokoly na základě teoretických znalostí. Druhá část práce se zaobírá návrhem a implementací testbedu, který je následně použitý pro praktické porovnání proof-of-stake protokolů. V závěrečné částí práce je diskutováno nad zjištěnými výsledky pozorováním testbedu a zjištěnými vlatnostmi protokolů. Na tomto základě práce ve svém konci naznačuje další směřování consesus protokolů, ba jejich případné zlepšení, a zvláště proof-of-stake typu protokolů.

Zisang Xu, Feng Li, Han Deng, Minfu Tan · 6 authors

With the rapid development of mobile networks, there are more and more application scenarios that require group communication. For example, in mobile edge computing, group communication can be used to transmit messages to all group members with minimal resources. The group key directly affects the security of the group communication. Most existing group key agreement protocols are often flawed in performance, scalability, forward or backward secrecy, or single node failure. Therefore, this paper proposes a blockchain-based authentication and dynamic group key agreement protocol. With our protocol, each group member only needs to authenticate its left neighbor once to complete the authentication, which improved authentication efficiency. In addition, our protocol guarantees the forward secrecy of group members after joining the group and the backward secrecy of group members after leaving the group. Based on blockchain technology, we solve the problem of single node failure. Furthermore, we use mathematics to prove the correctness and security of our protocol, and the comparison to related protocols shows that our protocol reduces computation and communication costs.

Ken Naganuma, Takayuki Suzuki, Masayuki Yoshino, Kenta Takahashi · 6 authors

Blockchain technology is attracting attention as an innovative system for decentralized payments in fields such as financial area. On the other hand, in a decentralized environment, management of a secret key used for user authentication and digital signature becomes a big issue because if a user loses his/her secret key, he/she will also lose assets on the blockchain. This paper describes the secret key management issues in blockchain systems and proposes a solution using a biometrics-based digital signature scheme. In our proposed system, a secret key to be used for digital signature is generated from the user's biometric information each time and immediately deleted from the memory after using it. Therefore, our blockchain system has the advantage that there is no need for storage for storing secret keys throughout the system. As a result, the user does not have a risk of losing the key management devices and can prevent attacks from malware that steals the secret key.

Chin‐Ling Chen, Yong‐Yuan Deng, Wei Weng, Hongyu Sun · 5 authors

In recent years, blockchain-related technologies and applications have gradually emerged. Blockchain technology is essentially a decentralized database maintained by the collective, and it is now widely applied in various fields. At the same time, with the growth of medical technology, medical information is becoming increasingly important in terms of patient identity background, medical payment records, and medical history. Medical information can be the most private information about a person, but due to issues such as operation errors within the network or a hacking attack by a malicious person, there have been major leaks of sensitive personal information in the past. In any case, this has become an issue worth studying to ensure the privacy of patients and protect these medical materials. On the other hand, under the current medical system, the patient’s EMR (electronic medical record) cannot be searched across the hospital. When the patient attends the hospital for treatment, repeated examinations will occur, resulting in a waste of medical resources. Therefore, we propose a blockchain-based secure inter-hospital EMR sharing system in this article. Through the programmatic authorization mechanism by smart contracts, the security of EMR is guaranteed. In addition to the essential mutual authentication, the proposed scheme also provides and guarantees data integrity, nonrepudiation, user untraceability, forward and backward secrecy, and resistance to replay attack.

Cherukupalli Veda Vyasa Aditya, Rajesh Kannan Megalingam

Zero knowledge proof is a powerful cryptographic protocol that is utilized to establish data security whilst ensuring and maintaining user anonymity. ZKP has relatively less complex computational requirements as compared to the other protocols for authentication. Conventional authentication schemes are susceptible to attacks such as MiTM, IP spoofing, DoS, replay and other eavesdropping based attacks, when the data is shared across an untrusted network. This paper shows an approach to ensure authentication of a device over an untrusted network whilst maintaining and safeguarding user credentials, by using the concepts of ZKP protocol.

Mohammad Wazid, Ashok Kumar Das, Sachin Shetty, Joel J. P. C. Rodrigues

On the basis of the Internet of Things (IoT) applications, several variants such as Internet of Energy (IoE), Internet of Vehicles (IoV), Internet of Drones (IoD), Internet of Medical Things (Internet of Health, IoMT) and Internet of Intelligent Battlefield Things (IoIBT) are developed. The smart devices involved in IoT can also utilize artificial intelligence algorithm (i.e., machine learning) to make the communication environment more effective and efficient. Intelligent Battlefield Things (IBT) communication environment is an example of that kind. It consists of smart and intelligent devices (i.e., drones), which monitor the activities of the enemies and retaliate accordingly. Hence, we need very less or negligible human involvement. IBT communication environment is very suitable for the purpose of battlefield communication (i.e., war zone, target tracking and hitting, border area surveillance and retaliation). However, IBT has certain drawbacks, because it may be vulnerable to different types of attacks, such as replay, man-in-the-middle, impersonation, data modification, data leakage attacks, etc. Therefore, it becomes essential to provide a security mechanism to secure the communication that happens in IBT environment. To achieve this purpose, we propose a secure communication framework for the blockchain of IBT environment. In addition, the benefits of applications of blockchain of IBT are discussed. The issues and challenges of blockchain of IBT environment are also highlighted. Finally, a security analysis of the proposed framework is conducted to depict its resilience against possible attacks.

Wenzheng Liu, Xiaofeng Wang, Wei Peng

In the communication environment of smart homes, personal data, control messages, and sensitive data are transmitted through wireless sensor networks (WSNs). Therefore, to prevent an invasion of privacy, communication has to be encrypted, and the data have to be stored securely. In this paper, we propose a new secure privacy-preserving authentication scheme for smart homes. We propose the concept of non-interactive chaotic zero-knowledge proof (NCZKP) and use it for our scheme to resist ephemeral secrets leakage (ESL) impersonation attack, which assures that the adversary can extract the sensitive information stored in gateway note, and use it to impersonate as a legal user. Also, the formal security analysis Random-or-real model is used to prove that our scheme is secure against different known attacks. In the end, according to the experiment, our scheme has low computation and communication costs compare with other related schemes.

Salabat Khan, Liehuang Zhu, Xiaoyan Yu, Zijian Zhang · 8 authors

No abstract is available for this record.

Chao Lin, Debiao He, Xinyi Huang, Neeraj Kumar · 5 authors

While Vehicular Ad-hoc Networks (VANETs) can potentially improve driver safety and traffic mangement efficiency (e.g. through timely sharing of traffic status among vehicles), security and privacy are two ongoing issues that need to be addressed. Hence, security solutions such as conditional privacy-preserving authentication (CPPA) protocols have been proposed. However, CPPA protocols are generally far from being ready for deployment in VANETs, for example due key/certificate management limitations in PKI-based protocols or intractable private key updating in ID-based protocols. Although serveral blockchain-based CPPA (BCPPA) protocols have been proposed to mitigiate these challenges, there still exist some intractabilities such as revoking private key, or frequent interactions, or requiring an idea hardware. Thus, in this paper, we are motivated to propose a novel BCPPA protocol without these existing issues. Specifically, we present a PKI-based solution (using a typical digital signature protocol, such as ECDSA) based on Ethereum (a public blockchain), which is designed to facilitate secure communication in VANETs. In other words, we combine the blockchain technology and a key derivation algorithm to realize an effective certificate management. This reduces the need for participating vehicles to store a large number of private keys. To reduce the verification time cost, our BCPPA suppotrs replacing ECDSA with modified ECDSA for batch verification or directly adopting other PKI-based signatures with batch verification. In addition to introducing the concrete design, we also present the security requirements that our BCPPA protocol can satisfy. We then implement BCPPA in the Ethereum test network (i.e.Rinkeby) and provide simulations using VanetMobiSim and NS-2 to show its feasibility (i.e. milliseconds).

Qikun Zhang, Yongjiao Li, Ruifang Wang, Jianyong Li · 7 authors

No abstract is available for this record.

Xinyi Huang, Yuexin Zhang

No abstract is available for this record.