The Experts below are selected from a list of 4563 Experts worldwide ranked by ideXlab platform
Zekeriya Erkin - One of the best experts on this subject based on the ideXlab platform.
-
a scale out blockchain for value transfer with spontaneous sharding
International Cryptology Conference, 2018Co-Authors: Zhijie Ren, Kelong Cong, Taico Aerts, Bart De Jonge, Alejandro Morais, Zekeriya ErkinAbstract:Bitcoin, as well as many of its successors, require the whole Transaction Record to be reliably acquired by all nodes to prevent double-spending. Recently, many blockchains have been proposed to achieve scale-out throughput by letting nodes only acquire a fraction of the whole Transaction set. However, these schemes, e.g., sharding and off-chain techniques, suffer from a degradation in decentralization or the capacity of fault tolerance. In this paper, we show that the complete set of Transactions is not a necessity for the prevention of double-spending if the properties of value transfers is fully explored. In other words, we show that a value-transfer ledger like Bitcoin has the potential to scale-out by its nature without sacrificing security or decentralization. Firstly, we give a formal definition for the value-transfer ledger and its distinct features from a generic database. Then, we introduce the blockchain structure with a shared main chain for consensus and an individual chain for each node for Recording Transactions. A locally executable validation scheme is proposed with uncompromising validity and consistency. A beneficial consequence of our design is that nodes will spontaneously try to reduce their transmission cost by only providing the Transactions needed to show that their Transactions are not double spend. As a result, the network is sharded as each node only acquires part of the Transaction Record and a scale-out throughput could be achieved, which we call "spontaneous sharding".
-
a scale out blockchain for value transfer with spontaneous sharding
arXiv: Distributed Parallel and Cluster Computing, 2018Co-Authors: Zhijie Ren, Zekeriya ErkinAbstract:Bitcoin, as well as many of its successors, require the whole Transaction Record to be reliably acquired by all nodes to prevent double-spending. Recently, many blockchains have been proposed to achieve scale-out throughput by letting nodes only acquire a fraction of the whole Transaction set. However, these schemes, e.g., sharding and off-chain techniques, suffer from a degradation in decentralization or the capacity of fault tolerance. In this paper, we show that the complete set of Transactions is not a necessity for the prevention of double-spending if the properties of value transfers is fully explored. In other words, we show that a value-transfer ledger like Bitcoin has the potential to scale-out by its nature without sacrificing security or decentralization. Firstly, we give a formal definition for the value-transfer ledger and its distinct features from a generic database. Then, we introduce an off-chain based scheme with a shared main chain for consensus and an individual chain for each node for Recording Transactions. A locally executable validation scheme is proposed with uncompromising validity and consistency. A beneficial consequence of our design is that nodes will spontaneously try to reduce their transmission cost by only providing the Transactions needed to show that their Transactions are double-spending-proof. As a result, the network is sharded as each node only acquires part of the Transaction Record and a scale-out throughput could be achieved, which we call "spontaneous sharding".
Abdelouahed Gherbi - One of the best experts on this subject based on the ideXlab platform.
-
privacy preserving smart grid traceability using blockchain over iot connectivity
ACM Symposium on Applied Computing, 2021Co-Authors: Aamir Shahzad, Kaiwen Zhang, Abdelouahed GherbiAbstract:Smart grid (SG) technology comes with various advantages, among others, of efficient power distribution, reduction in cost consumption, maintain energy loss, and peak quality level in its supply chain. SG aims to provide all required and advanced features to overcome the issues of the existing power grid and to fulfill the rapidly growing demands of power generation, transmission, distribution, and monitoring energy consumption. However, SG has been facing various challenges to ensure the nature of every Transaction, Transaction verification, and Recording in the power supply chain, especially in the context of a large scale IoT(Internet of things) network. Another issue is maintaining the privacy of every Transaction, as well as the privacy of participating entities in the power supply chain. In this paper, we propose a blockchain-based proof-of-concept solution to manage every Transaction that occurs in an IoT-aided smart grid system. Our solution, IoT-aided smart grid system with blockchain, provides an immutable Transaction Record, which is always shared and transparent to each participant of the system. Transactions are carried through IoT objects connected in a smart grid, and are Recorded, verified, and validated on a blockchain immutable ledger. Furthermore, to verify and maintain the privacy of participants, cryptographic pseudonyms are used by each participant to interact with the SG supply chain, without revealing personal identities and important private information of the participants to malicious entities in the system.
Zhijie Ren - One of the best experts on this subject based on the ideXlab platform.
-
a scale out blockchain for value transfer with spontaneous sharding
International Cryptology Conference, 2018Co-Authors: Zhijie Ren, Kelong Cong, Taico Aerts, Bart De Jonge, Alejandro Morais, Zekeriya ErkinAbstract:Bitcoin, as well as many of its successors, require the whole Transaction Record to be reliably acquired by all nodes to prevent double-spending. Recently, many blockchains have been proposed to achieve scale-out throughput by letting nodes only acquire a fraction of the whole Transaction set. However, these schemes, e.g., sharding and off-chain techniques, suffer from a degradation in decentralization or the capacity of fault tolerance. In this paper, we show that the complete set of Transactions is not a necessity for the prevention of double-spending if the properties of value transfers is fully explored. In other words, we show that a value-transfer ledger like Bitcoin has the potential to scale-out by its nature without sacrificing security or decentralization. Firstly, we give a formal definition for the value-transfer ledger and its distinct features from a generic database. Then, we introduce the blockchain structure with a shared main chain for consensus and an individual chain for each node for Recording Transactions. A locally executable validation scheme is proposed with uncompromising validity and consistency. A beneficial consequence of our design is that nodes will spontaneously try to reduce their transmission cost by only providing the Transactions needed to show that their Transactions are not double spend. As a result, the network is sharded as each node only acquires part of the Transaction Record and a scale-out throughput could be achieved, which we call "spontaneous sharding".
-
a scale out blockchain for value transfer with spontaneous sharding
arXiv: Distributed Parallel and Cluster Computing, 2018Co-Authors: Zhijie Ren, Zekeriya ErkinAbstract:Bitcoin, as well as many of its successors, require the whole Transaction Record to be reliably acquired by all nodes to prevent double-spending. Recently, many blockchains have been proposed to achieve scale-out throughput by letting nodes only acquire a fraction of the whole Transaction set. However, these schemes, e.g., sharding and off-chain techniques, suffer from a degradation in decentralization or the capacity of fault tolerance. In this paper, we show that the complete set of Transactions is not a necessity for the prevention of double-spending if the properties of value transfers is fully explored. In other words, we show that a value-transfer ledger like Bitcoin has the potential to scale-out by its nature without sacrificing security or decentralization. Firstly, we give a formal definition for the value-transfer ledger and its distinct features from a generic database. Then, we introduce an off-chain based scheme with a shared main chain for consensus and an individual chain for each node for Recording Transactions. A locally executable validation scheme is proposed with uncompromising validity and consistency. A beneficial consequence of our design is that nodes will spontaneously try to reduce their transmission cost by only providing the Transactions needed to show that their Transactions are double-spending-proof. As a result, the network is sharded as each node only acquires part of the Transaction Record and a scale-out throughput could be achieved, which we call "spontaneous sharding".
Chiara Von Gunten - One of the best experts on this subject based on the ideXlab platform.
-
chain of a lifetime how blockchain technology might transform personal insurance
Social Science Research Network, 2014Co-Authors: Michael Mainelli, Chiara Von GuntenAbstract:"Chain Of A Lifetime: How Blockchain Technology Might Transform Personal Insurance" is the outcome of a research project conducted between August and December 2014 which explored how blockchain technology might transform personal insurance and in particular interactions among individuals and insurance companies over time. Blockchain technology's main innovation is an electronic public Transaction Record of integrity without central authority. Beside cryptocurrencies and distributed payment systems, blockchain applications could include areas of finance where a central, trusted third party has traditionally been used, trade reporting, depository receipts, escrow accounts or trade finance. Blockchains can contain set of documents, Record assets and help to manage interconnected devices. Emerging applications, such as smart contracts and decentralised autonomous organisations, might in future also permit blockchains to act as automated agents. The report concludes that blockchain technology could transform the way people manage identities and personal information; blur even further the divide between global and local; influence consumer perception of time; drive honesty and transparency; and, influence consumer perceptions of risk that could change the way insurers support mutualisation. The report highlights how, at the time of writing, most insurance companies do not yet seem ready to experiment with blockchain technology. They find it difficult enough to understand Bitcoin or cryptocurrencies. Non-insurers are more likely to be the first to create insurance or insurance-related applications. Blockchain applications in insurance are likely to start with digital identity systems and management of personal data.
Xiaodong Lin - One of the best experts on this subject based on the ideXlab platform.
-
ptas privacy preserving thin client authentication scheme in blockchain based pki
Future Generation Computer Systems, 2019Co-Authors: Wenbo Jiang, Mi Wen, Guishan Dong, Xiaodong LinAbstract:Abstract Recent years have witnessed tremendous academic efforts and industry growth in Internet of Things (IoT). Security issues of IoT have become increasingly prominent. Public Key Infrastructure (PKI) can provide authentication service to IoT devices which is a crucial element to the security of IoT. However, the conventional PKIs are organized as a tree-like centralized structure which has demonstrated serious usability and security shortcomings such as the single point of failure. Blockchain has numerous desirable properties, such as decentralized nature, cryptographic technology and unalterable Transaction Record, these properties make it a potential tool to build a decentralized blockchain-based PKI. Nevertheless, the latest proposals for blockchain-based PKI did not take thin-clients into consideration where thin-clients indicate those users who cannot download the entire blockchain due to the limited storage capacity of their equipment (most IoT devices fall into this category). To settle this problem, we firstly present a Privacy-preserving Thin-client Authentication Scheme (PTAS) employing the idea of private information retrieval (PIR), which enables thin-clients to run normally like full node users and protect their privacy simultaneously. Furthermore, in order to enhance security, we further propose a ( m -1)-private PTAS which means thin-client’s information can be protected against a collusion of at most ( m -1) full node users. Besides, security analysis and functional comparison are performed to demonstrate high security and comprehensive functionality of our schemes. Finally, extensive experiments are conducted to compare computational overhead and communication overhead of PTAS and ( m -1)-private PTAS.