Blockchain Papers

Olamide Timothy Tawose

No abstract is available for this record.

Michael Adams, Suriadi Suriadi, Akhil Kumar, Arthur H. M. ter Hofstede

No abstract is available for this record.

Sungyong Cha, Seungsoo Baek, Seungjoo Kim

The security of operation and maintenance phase in systems that share long-life cycles like weapon systems is of great importance. Even if the system passes the security evaluation at the development stage before release, it can be adversely affected by the penetration of counterfeit components (parts) during the operation and maintenance phase. Such security issues are concatenated with data related to supply chain, accordingly, system parts need to fulfill the traceability on a fundamental basis. In addition to traceability, supply chains should also meet the data security standards of availability, integrity and confidentiality in the long run. Also, even without trusted third party, these data should be available to users. In this paper, we, therefore, propose a framework that utilizes blockchain and key escrow encryption system in a bid to optimize the security of supply chains for long-lifecycle systems and provide better measures to improve services for global business survivability.

B. Arunkumar, G. Kousalya

No abstract is available for this record.

Zhang Lejun, Peng Minghui, Weizheng Wang, Yansen Su · 6 authors

In the digital era, electronic medical record (EMR) has been a major way for hospitals to store patients’ medical data. The traditional centralized medical system and semi-trusted cloud storage are difficult to achieve dynamic balance between privacy protection and data sharing. The storage capacity of blockchain is limited and single blockchain schemes have poor scalability and low throughput. To address these issues, we propose a secure and efficient medical data storage and sharing scheme based on double blockchain. In our scheme, we encrypt the original EMR and store it in the cloud. The storage blockchain stores the index of the complete EMR, and the shared blockchain stores the index of the shared part of the EMR. Users with different attributes can make requests to different blockchains to share different parts according to their own permissions. Through experiments, it was found that cloud storage combined with blockchain not only solved the problem of limited storage capacity of blockchain, but also greatly reduced the risk of leakage of the original EMR. Content Extraction Signature (CES) combined with the double blockchain technology realized the separation of the privacy part and the shared part of the original EMR. The symmetric encryption technology combined with Ciphertext-Policy Attribute-Based Encryption (CP–ABE) not only ensures the safe storage of data in the cloud, but also achieves the consistency and convenience of data update, avoiding redundant backup of data. Safety analysis and performance analysis verified the feasibility and effectiveness of our scheme.

Mohammad Sadeq Dousti, Alptekın Küpçü

No abstract is available for this record.

Qifeng Shao, Shuaifeng Pang, Zhao Zhang, Cheqing Jing

No abstract is available for this record.

Macià Mut–Puigserver, Miquel À. Cabot-Nadal, M. Magdalena Payeras–Capellà

Recently several proposals of blockchain-based solutions for traditional e-commerce applications have been presented, taking advantage of the fact that blockchain is a technology that offers an immutable registry of data. Among these proposals we can find solutions for certified notifications, digital signature of contracts, escrow protocols, fair payments and registered deliveries. In order to execute fair exchanges, most solutions involve trusted third parties, known as TTP, supervising the exchanges in a way or another. Until now, two solutions have been presented for Registered electronic Delivery (eDelivery) services. This service allows a user to prove that he has sent some data to a set of receivers. These protocols differ in the properties achieved and also in the use of trusted third parties. The first protocol is a blockchain-based solution without TTP for the eDelivery of non-confidential data. The second protocol allows also the eDelivery of confidential data. However, this second proposal requires the involvement of a TTP in a non-mandatory resolution phase. In this paper we present a new protocol that achieves the best properties of the previous solutions at the same time. The new protocol doesn't require the involvement of a TTP at any moment while it allows the eDelivery of confidential data, satisfying the security requirements for this service.

J. Tan

Since the birth of Blockchain technology in 2008, it has been widely implemented in areas of finance, most notably as a cryptocurrency which now has real-world monetary value. The rise of blockchain can be attributed to its unique characteristics: being trust-less, immutable and decentralized. There are companies who adopt private blockchains in general. However, with the emergence of special products such as Infrastructure as a Service that ease blockchain implementation issues, the public blockchains are steadily garnering interests not just from companies but from aspiring blockchain developers as well. 
\nThis project will develop a mobile application using Ethereum, an open-source and public blockchain platform that enables developers to create decentralized applications with it along with Android Studio to create the application for mobile usage. Then, security testing is performed on the application. Using the observations from the tests, we will be able to identify threats that the blockchain environment can and cannot prevent.

Kai He, Jiaoli Shi, Chunxiao Huang, Xinrong Hu

No abstract is available for this record.

Muhammad Shoaib Siddiqui, Toqeer Ali, Adnan Nadeem, Waqas Nawaz · 5 authors

Data tracking is of great significance and a central part in digital forensics. In today's complex network design, Internet of Things (IoT) devices communicate with each other and require strong security mechanisms. In maintaining an audit trail of IoT devices or provenance of IoT device data, it is important to know the origins of requests to ensure certain level of trust in IoT data. Blockchain can provide traceability of records generated from IoT devices in a sensitive environment. In this paper, we present an application layer data provenance model that works on execute-order architecture for cloud based IoT networks. It supports high throughput of transactions on the blockchain network with lightweight security overhead by using outsourced encryption on edge nodes. All communications among the IoT devices are connected to a blockchain network and stored on permissioned blockchain peers. The proposed system is evaluated to have less cryptographic load by offloading the IoT nodes with Edge nodes.

Jan Ladleif, Ingo Weber, Mathias Weske

No abstract is available for this record.

Garvit Chhajed, Hitesh Jethani, Anagha Pokharkar, Himanshu Bhutani · 5 authors

Cryptocurrencies are getting massive momentum in the last few years. Cryptocurrencies depend upon a secure distributed ledger called blockchain which stores blocks in a secure and chronological order. Although a large cryptocurrencies wallet management scheme has been proposed but they suffer from weak security. Thus effective cryptocurrency key management has become a much needed requirement for modern cryptocurrencies. In this paper, we propose a more effective, usable and secure cryptocurrency key management system named rashi that provides security enhanced storage, no password authentication. The performance analysis shows that our proposed system requires minimal additional overhead and has low time delays, enhanced security and efficient real -world deployment.

Ting Cai, Zetao Yang, Wuhui Chen, Zibin Zheng · 5 authors

The Solid (Social Linked Data) project focuses on data sharing and privacy security and aims to build a decentralized ecosystem that radically changes the way web applications work today. Our goal is to introduce a “trust access authentication system” to achieve secure authentication and fine-grained access control, thereby promoting the implementation of Solid. Blockchain, equipped with multiple security properties and authentication functions, is a crucial technology. In this paper, we present a blockchain-assisted system for secure authentication in Solid and for implementation of fine-grained access control policies. Specifically, we explore to integrate threshold RSA signatures in a permissioned blockchain system to enable a fault-tolerant distributed signature scheme, thereby enhancing the resilience and robustness of authentication system. Moreover, we utilize smart contract to control transaction flows and manage access control policies automatically. Experimental results show that our proposed trust access authentication system enhances security, scales well, and is efficient and economically feasible.

Fabian Bendun

In this thesis, we present novel methods for verifying, implementing and specifying protocols. In particular, we focus properties modeling data protection and the protection of privacy. In the first part of the thesis, the author introduces protocol verification and presents a model for verification that encompasses so-called Zero-Knowledge (ZK) proofs. These ZK proofs are a cryptographic primitive that is particularly suited for hiding information and hence serves the protection of privacy. The here presented model gives a list of criteria which allows the transfer of verification results from the model to the implementation if the criteria are met by the implementation. In particular, the criteria are less demanding than the ones of previous work regarding ZK proofs. The second part of the thesis contributes to the area of protocol implementations. Hereby, ZK proofs are used in order to improve multi-party computations. The third and last part of the thesis explains a novel approach for specifying data protection policies. Instead of relying on policies, this approach relies on actual legislation. The advantage of relying on legislation is that often a fair balancing is introduced which is typically not contained in regulations or policies.

Authors unavailable

No abstract is available for this record.

Hisham S. Galal, Amr Youssef

No abstract is available for this record.

Adriano Martins Ribeiro, Luiz Santos, A. L. dos S. Furtado, Bruna Schröder · 6 authors

No abstract is available for this record.

Joosep Simm, Jamie Steiner, Ahto Truu

No abstract is available for this record.

Jørgen Holme

Moving large amounts of data between networks for data analysis and computations presents several issues related to privacy and security. In collaboration with the TOTEM project [1], we propose a solution to these problems, by moving computations to the residence of the data. We introduce a novel approach for managing access to remote datasets and resources by blockchain technology through Hyperledger Fabric. Organizations with similar interests may join a consortium, which will form a private channel on the blockchain network, i.e., a separate ledger. Participating organizations will enroll their users, who thereafter must obtain a one-time-code using a smart contract in order to gain access to remote resources. We utilize Ansible for remotely deploying Hadoop clusters for computation, which will comprise several Docker containers. A user may run computations at several remote locations separately, and subsequently retrieve a combined result without having to share data between organizations. To ensure privacy between participating organizations we utilize chaincode and private data collections in Hyperledger Fabric. Finally, we demonstrate three ways of deploying the solution: locally, as a single cluster in the cloud using Azure, and across multiple clusters in the cloud using Azure. Our solution ensures data privacy by allowing data providing organizations to connect their own computational resources for data consumers to use. By running computations inside Docker containers on these resources, we ensure that these processes are isolated from the host system.

Ada Bagozi, Devis Bianchini, Valeria De Antonellis, Massimiliano Garda · 5 authors

No abstract is available for this record.

Maxim Jourenko, Mario Larangeira, Keisuke Tanaka

No abstract is available for this record.

Hanlei Cheng, Jing Lu, Zhiyu Xiang, Bin Song

No abstract is available for this record.

Leonard Kleinrock, Rafail Ostrovsky, Vassilis Zikas

No abstract is available for this record.