Related Papers
International Conference on Blockchain Economics, Security and Protocols, Tokenomics 2019, May 6-7, 2019, Paris, France
2020 •
julien prat
Bitcoin is a successful and interesting example of a global scale peer-to-peer cryptocurrency that integrates many techniques and protocols from cryptography, distributed systems, and databases. The main underlying data structure is blockchain, a scalable fully replicated structure that is shared among all participants and guarantees a consistent view of all user transactions by all participants in the cryptocurrency system. The novel aspect of Blockchain is that historical data about all transactions is maintained in the absence of any central authority. This property of Blockchain has given rise to the possibility that future applications will transition from centralized databases to a fully decentralized storage based on blockchains. In this talk, we start by developing an understanding of the basic protocols used in blockchain, and elaborate on their main advantages and limitations. To overcome these limitations, we will explore some of the challenges of managing large scale ful...
The Security Reference Architecture for Blockchains: Towards a Standardized Model for Studying Vulnerabilities, Threats, and Defenses
2020 •
Ivan hom*oliak
Due to their specific features, such as decentralization and immutability, blockchains have become popular in recent years. Blockchains are full-stack distributed systems in terms of realization, where security is a critical factor for their success. However, despite increasing popularity and adoption, there is a lack of standardized models to study security threats related to blockchains in a similar fashion as was done, e.g., in the area of cloud computing [236], [384]. To fill this gap, the main focus of our work is to systematize the knowledge about security and privacy aspects of blockchains, and thus contribute to the standardization of this domain. To this end, we propose the security reference architecture for blockchains, which utilizes a stacked model (similar to the ISO/OSI) that demonstrates the nature and hierarchy of various security and privacy threats. The model contains four layers: (1) the network layer, (2) the consensus layer, (3) the replicated state machine layer, and (4) the application layer. At each of these layers, we identify known security threats, their origin as well as mitigation techniques or countermeasures. Although a similar model has already been used in previous work to serve as a general outline of the blockchain infrastructure, we adapt it for the purpose of studying security threats in this domain. Further, we propose a blockchain-specific version of the threat-risk assessment standard ISO/IEC 15408 by embedding the stacked model into this standard. Finally, following our stacked model and its categorization, we provide an extensive survey of blockchain-oriented and related research as well as its applications.
Future Internet
Blockchain Technology for Intelligent Environments
2019 •
Vasilios A Siris
In the last few years, we have been witnessing the convergence of the physical with the digital world. The Internet of Things (IoT) is progressing at a fast pace, and IoT devices are becoming pervasive in our physical environments, bringing the vision of Intelligent Environments closer to reality. At the same time, the newly-introduced blockchain technology is offering for the first time ever cryptographically proven trust based on a set of mutually untrusted nodes. Blockchain technology thus has the potential to become a key component of many IoT systems, offering them an unprecedented level of accountability, transparency, and reliability. This paper first lays out the principles on which blockchain systems are operating, along with descriptions of the most noteworthy blockchain implementations. It then presents a number of systems through which blockchains may interact with external systems and third-party data sources. Finally, it provides a survey of the state-of-the-art blockc...
2016 13th Working IEEE/IFIP Conference on Software Architecture (WICSA)
The Blockchain as a Software Connector
2016 •
An Tran
Engineering Journal
Blockchain Technology, Technical Challenges and Countermeasures for Illegal Data Insertion
2020 •
Muhammad Aitsam
ArXiv
Enabling Blockchain Scalability and Interoperability with Mobile Computing through LayerOne.X
2021 •
Kevin Coutinho
Interoperability and scalability are currently the bottlenecks preventing mass adoption of blockchain technology. Development of an interoperable and scalable network that promotes a truly decentralised, permissionless and secure blockchain as well as one that enables micro validation is the main goal of this project. Layer-One.X, a truly decentralised ledger which utilises para-sharding, Directed Acyclic Graphs, Proof of Participation consensus mechanism, mobile computing, flash contracts and nucleus scripting is introduced in this paper. The conceptual framework including tokenomics is also explained along with a number of use cases. The framework facilitates the growing need of transaction per second enabling micro based payments and value transfer through tokenisation.
SN Computer Science
A Survey on Blockchain Technology Concepts, Applications, and Issues
2020 •
Dr. Dhammika Weerasinghe
Assessing Security and Performances of Consensus algorithms for Permissioned Blockchains
Stefano De Angelis
Blockchain is a novel technology that is rising a lot of interest in the industrial and re- search sectors because its properties of decentralisation, immutability and data integrity. Initially, the underlying consensus mechanism has been designed for permissionless block- chain on trustless network model through the proof-of-work, i.e. a mathematical challenge which requires high computational power. This solution suffers of poor performances, hence alternative consensus algorithms as the proof-of-stake have been proposed. Conversely, for permissioned blockchain, where participants are known and authenti- cated, variants of distributed consensus algorithms have been employed. However, most of them comes out without formal expression of security analysis and trust assumptions because the absence of an established knowledge. Therefore the lack of adequate analysis on these algorithms hinders any cautious evaluation of their effectiveness in a real-world setting where systems are deployed over trustless networks, i.e. Internet. In this thesis we analyse security and performances of permissioned blockchain. Thus we design a general model for such a scenario in a way to propose a general benchmark for the experimental evaluations. This work brings two main contributions. The first contribution concern the analysis of Proof-of-Authority, a Byzantine Fault- Tolerant consensus protocol. We compare two of the main algorithms, named Aura and Clique, with respect the well-established Practical Byzantine Fault-Tolerant, in terms of se- curity and performances. We refer the CAP theorem for the consistency, availability and partition tolerance guarantees and we describe a possible attack scenario in which one of the algorithms loses consistency. The analysis advocates that Proof-of-Authority for permissioned blockchains deployed over WANs experimenting Byzantine nodes, do not provide adequate consistency guarantees for scenarios where data integrity is essential. We claim that actually the Practical Byzantine Fault-Tolerant can fit better for permis- sioned blockchain, despite a limited loss in terms of performance. The second contribution is the realisation of a benchmark for practical evaluations. We design a general model for permissioned blockchain under which benchmarking perfor- mances and security guarantees. However, because no experiment can verify all the pos- sible security issues permitted by the model, we prototype an adversarial model which simulate three attacks, feasible for a blockchain system. We then integrate this attacker model in a real blockchain client to evaluate the resiliency of the system and how much the attacks impact performances and security guarantees.
IEEE Access
A Survey on Consensus Mechanisms and Mining Strategy Management in Blockchain Networks
2019 •
EKAMBARAM KESAVULU REDDY
A Review of Blockchain Architecture and Consensus Protocols: Use Cases, Challenges, and Solutions
Leila Ismail
ver the last decade the blockchain technology has emerged to provide solutions to the complexity, performance and privacy challenges of using distributed databases. Over this time, the concept of blockchain has shifted greatly due to the rapidly evolving distributed applications in a collaborative ecosystem such as smart cities, social networking, governance, and smart healthcare, and the ultimate need for green computing, cost reduction for customers, and business growth for enterprises. Consequently, blockchain architecture has misaligned with the goals for a green collaborative digital ecosystem. Therefore, it becomes critical to address this vent and to build new frameworks to align blockchain with those goals. In this paper, we discuss the evolution of blockchain architecture and its consensus protocols, bringing a retrospective analysis and discussing the rationale of the evolution of the various architectures and protocols, as well as capturing the assumptions conducting to t...
