10,783 research outputs found

    Blockchain And The Future of the Internet: A Comprehensive Review

    Full text link
    Blockchain is challenging the status quo of the central trust infrastructure currently prevalent in the Internet towards a design principle that is underscored by decentralization, transparency, and trusted auditability. In ideal terms, blockchain advocates a decentralized, transparent, and more democratic version of the Internet. Essentially being a trusted and decentralized database, blockchain finds its applications in fields as varied as the energy sector, forestry, fisheries, mining, material recycling, air pollution monitoring, supply chain management, and their associated operations. In this paper, we present a survey of blockchain-based network applications. Our goal is to cover the evolution of blockchain-based systems that are trying to bring in a renaissance in the existing, mostly centralized, space of network applications. While re-imagining the space with blockchain, we highlight various common challenges, pitfalls, and shortcomings that can occur. Our aim is to make this work as a guiding reference manual for someone interested in shifting towards a blockchain-based solution for one's existing use case or automating one from the ground up.Comment: Under Review in IEEE COMS

    IDMoB: IoT Data Marketplace on Blockchain

    Full text link
    Today, Internet of Things (IoT) devices are the powerhouse of data generation with their ever-increasing numbers and widespread penetration. Similarly, artificial intelligence (AI) and machine learning (ML) solutions are getting integrated to all kinds of services, making products significantly more "smarter". The centerpiece of these technologies is "data". IoT device vendors should be able keep up with the increased throughput and come up with new business models. On the other hand, AI/ML solutions will produce better results if training data is diverse and plentiful. In this paper, we propose a blockchain-based, decentralized and trustless data marketplace where IoT device vendors and AI/ML solution providers may interact and collaborate. By facilitating a transparent data exchange platform, access to consented data will be democratized and the variety of services targeting end-users will increase. Proposed data marketplace is implemented as a smart contract on Ethereum blockchain and Swarm is used as the distributed storage platform.Comment: Presented at Crypto Valley Conference on Blockchain Technology (CVCBT 2018), 20-22 June 2018 - published version may diffe

    Bitcoin and Decentralized Trust Protocols

    Full text link
    Bitcoin is the first decentralized peer-to-peer (P2P) electronic currency. It was created in November 2008 by Satoshi Nakamoto. Nakamoto released the first implementation of the protocol in an open source client software and the genesis of bitcoins began on January 9th 2009. The Bitcoin protocol is based on clever ideas which solve a form of the Byzantine Generals Problem and sets the foundation for Decentralized Trust Protocols. Still in its infancy, the currency and the protocol have the potential to disrupt the international financial system and other sectors where business is based on trusted third parties. The security of the bitcoin protocol relies on strong cryptography and one way hashing algorithms.Comment: This is a general survey article to appear on the June 2016 issue of the Newsletter of the EMS. 8 pages, 5 figure

    ISMA-DS/CDMA MAC protocol for mobile packet radio networks

    Get PDF
    In this paper an ISMA-DS/CDMA MAC protocol for a packet transmission network is presented. The main feature of this protocol is its ability to retain the inherent flexibility of random access protocols while at the same time reducing to some extent the randomness in the access in order to increase the system capacity. In this framework, the protocol is adapted to a frame structure similar to that specified in the UTRA ETSI proposal for third generation mobile communication systems. Additionally, some adaptive mechanisms are proposed that improve protocol performance by means of varying the transmission bit rate according to the channel load that is broadcast by the base station. As a result, an adaptive bit rate algorithm is presented that reaches a throughput value close to the optimumPeer ReviewedPostprint (published version

    Efficiency of financial micro intermediation in the WAEMU countries: A stochastic frontier production analysis.

    Get PDF
    This paper investigates the efficacy and technical efficiency of financial micro intermediation in the productive process of the WAEMU economies over the period 2002-2007 using a stochastic frontier production model with technical inefficiency effects. Four specific variables of the financial dualism deepening and the financial micro intermediation are considered: the ratio of microcredit to GDP, the microcredit growth rate, the share of microcredit in the economy financing due to the private sector and the agents preference for decentralized deposits. Our findings show that the four variables have positive effect on technical efficiency with 0.6 of semi-elasticity estimated on average whereas bank loans have on average only 0.3 on average. We conclude that the financial micro intermediation development which results from the financial dualism deepening makes it possible to almost double increase the productive efficiency in WAEMU area.Financial micro intermediation, financial dualism, stochastic frontier, technical efficiency, WAEMU

    Dynamic Resource Allocation in Cognitive Radio Networks: A Convex Optimization Perspective

    Full text link
    This article provides an overview of the state-of-art results on communication resource allocation over space, time, and frequency for emerging cognitive radio (CR) wireless networks. Focusing on the interference-power/interference-temperature (IT) constraint approach for CRs to protect primary radio transmissions, many new and challenging problems regarding the design of CR systems are formulated, and some of the corresponding solutions are shown to be obtainable by restructuring some classic results known for traditional (non-CR) wireless networks. It is demonstrated that convex optimization plays an essential role in solving these problems, in a both rigorous and efficient way. Promising research directions on interference management for CR and other related multiuser communication systems are discussed.Comment: to appear in IEEE Signal Processing Magazine, special issue on convex optimization for signal processin

    General Auction-Theoretic Strategies for Distributed Partner Selection in Cooperative Wireless Networks

    Full text link
    It is unrealistic to assume that all nodes in an ad hoc wireless network would be willing to participate in cooperative communication, especially if their desired Quality-of- Service (QoS) is achievable via direct transmission. An incentivebased auction mechanism is presented to induce cooperative behavior in wireless networks with emphasis on users with asymmetrical channel fading conditions. A single-object secondprice auction is studied for cooperative partner selection in singlecarrier networks. In addition, a multiple-object bundled auction is analyzed for the selection of multiple simultaneous partners in a cooperative orthogonal frequency-division multiplexing (OFDM) setting. For both cases, we characterize equilibrium outage probability performance, seller revenue, and feedback bounds. The auction-based partner selection allows winning bidders to achieve their desired QoS while compensating the seller who assists them. At the local level sellers aim for revenue maximization, while connections are drawn to min-max fairness at the network level. The proposed strategies for partner selection in self-configuring cooperative wireless networks are shown to be robust under conditions of uncertainty in the number of users requesting cooperation, as well as minimal topology and channel link information available to individual users.Comment: 13 pages, to appear, IEEE Transactions on Communication

    Blockchain for Future Smart Grid: A Comprehensive Survey

    Full text link
    The concept of smart grid has been introduced as a new vision of the conventional power grid to figure out an efficient way of integrating green and renewable energy technologies. In this way, Internet-connected smart grid, also called energy Internet, is also emerging as an innovative approach to ensure the energy from anywhere at any time. The ultimate goal of these developments is to build a sustainable society. However, integrating and coordinating a large number of growing connections can be a challenging issue for the traditional centralized grid system. Consequently, the smart grid is undergoing a transformation to the decentralized topology from its centralized form. On the other hand, blockchain has some excellent features which make it a promising application for smart grid paradigm. In this paper, we aim to provide a comprehensive survey on application of blockchain in smart grid. As such, we identify the significant security challenges of smart grid scenarios that can be addressed by blockchain. Then, we present a number of blockchain-based recent research works presented in different literatures addressing security issues in the area of smart grid. We also summarize several related practical projects, trials, and products that have been emerged recently. Finally, we discuss essential research challenges and future directions of applying blockchain to smart grid security issues.Comment: 26 pages, 13 figures, 5 table

    Blockchain Enabled Privacy Preserving Data Audit

    Full text link
    Data owners upload large files to cloud storage servers, but malicious servers may potentially tamper data. To check integrity of remote data, Proof of Retrievability (PoR) schemes were introduced. Existing PoR protocols assume that data owners and third-party auditors are honest and audit only the potentially malicious cloud server to check integrity of stored data. In this paper we consider a system where any party may attempt to cheat others and consider collusion cases. We design a protocol that is secure under such adversarial assumptions and use blockchain smart contracts to act as mediator in case of dispute and payment settlement. We use state channels to reduce blockchain interactions in order to build a practical audit solution. We implement and evaluate a prototype using Ethereum as the blockchain platform and show that our scheme has comparable performance
    • 

    corecore