Blockchain Papers

Pim Otte, Martijn de Vos, Johan Pouwelse

No abstract is available for this record.

Authors unavailable

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Francesco Buccafurri, Gianluca Lax, Serena Nicolazzo, Antonino Nocera

Blockchain technology allows the implementation of a public ledger securely recording transactions among peers without the need of trusted third parties. For both researchers and industry IoT appears a domain in which there would be extraordinary benefits if the features of Blockchain can be exploited. Indeed, the possibility that IoT devices participate in public shared transactions enables a lot of challenging applications. However, there are some aspects that may limit the use of Blockchain in IoT. These are mainly related to the low computational power and storage capabilities of IoT devices. In this paper, we propose an alternative way to implement a public ledger overcoming the above drawbacks, thus appearing more suitable to IoT applications. The proposed protocol leverages the popular social network Twitter and works by building a meshed chain of tweets to ensure transaction security. Importantly, Twitter does not play neither the role of trusted third party nor the role of ledger provider.

Josef Gattermayer, Pavel Tvrdı́k

Peer-to-peer (P2P) design offers many benefits over a single-master or a multi-master architecture in terms of scalability, reliability and independence. The Clondike project is being converted from a grid computing system into a universal non-dedicated P2P cluster where every participating node can benefit from its membership in the cluster. But different design requires different types of algorithms in order to guarantee the same functionality. One of the challenges in P2P design is a fair scheduling and a general protection of the whole cluster against abusive or malfunctioning nodes. Algorithms used in a single-master or multi-master clusters do not work anymore. We have designed a multi-level system based on one of the main principles of cryptocurrencies to achieve a distributed master-less reputation rating across the cluster. This paper discusses proposed cluster multi-level reputation system and its parameters. The system is evaluated on a Clondike cluster on an experimental measurement with abusive nodes involved.

Chengjun Cai, Xingliang Yuan, Cong Wang

Distributed storage platforms draw much attention due to their high reliability and scalability for handling a massive amount of data. To protect user and data privacy, encryption is considered as a necessary feature for production systems like Storj. But it prohibits the nodes from performing content search. To preserve the functionality, we observe that a protocol of integration with searchable encryption and keyword search via distributed hash table allows the nodes in a network to search over encrypted and distributed data. However, this protocol does not address a practical threat in a fully distributed scenario. Malicious nodes would sabotage search results, and easily infiltrate the system as the network grows. Using primitives such as MAC and verifiable data structure may empower the users to verify the search result, but the robustness of the overall system can hardly be ensured. In this paper, we address this issue by proposing a protocol that is seamlessly incorporated to encrypted search in distributed network to attest and monitor nodes. From the moment a node joins the system, it will be attested and continuously monitored through verifiable search queries. The result of each attestation is determined via a standard quorum-based voting protocol, and then recorded on the blockchain as a consensus view of trusted nodes. Based on the proposed protocols, malicious nodes can be detected and removed by a majority of nodes in a self-determining manner. To demonstrate the security and efficiency, we conduct robustness analysis against several potential attacks, and perform performance and overhead evaluation on the proposed protocol.

Bhumika Ekbote, Vaishnavi Hire, Pratik Mahajan, Jignesh Sisodia

A large number of people earn money in foreign countries and many of them have to send across the money back home in India. For every such transaction, multiple fees could be charged, varying from 3 to 12 percent. In this paper we offer a peer-to-peer settlement solution for such remittance on blockchain at negligible rates. Money transfers can be securely converted into crypto-currencies, which can easily be transferred across nations, and then again converted into local currencies. In this paper, we use Multi-chain for digital assets and peer-to-peer electronic cash systems where transactions take place between users directly, without an intermediary. These transactions are verified by network nodes and recorded in a public distributed ledger called the blockchain. Each block is verified and added to the blockchain (distributed public ledger), which includes all past transactions through a process known as Mining. Mining using CPU is unwise and has high cost of operation. We present an alternative approach using CUDA-enabled Graphics Processing Unit(GPU) for mining. The massively parallel nature of some GPUs majorly increases the mining power.

Yuan Liu, Zheng Zhao, Guibing Guo, Xingwei Wang · 6 authors

In this paper, we propose a decentralized identity management system based on Blockchain. The function of the system mainly includes identity authentication and reputation management. The technical advantages of the Blockchain makes the data in the system safe and credible. In addition, we use smart contracts to write system rules to ensure the reliability of user information. We bind the user's entity information with the public key address and determine the true identity of a virtual user on the Blockchain. We use the token to represent the reputation which is shown to be an effective reputation model, making the participants in the system prefer to maintain and manage their personal reputation. Our system makes it possible for users to securely manage their identity and reputation on the Internet.

Zhidong Chen, Zhuo Yu, Zhangbo Duan, Kai Hu

Blockchain technology is growing massively where the number of blockchain platforms and decentralized applications are increasing rapidly in the last years. However, most of the existing blockchain networks are operating in a standalone environment isolated from each other, which increases scalability and connectivity issues in the current blockchain platforms as well as limiting the blockchain adoption in industry ecosystems. In the current phase, different blockchain networks don't have mutual trust where they cannot interact with each other and their capacity level has only reached a level similar to LAN. Due to the high barriers between the independent isolated blockchain platforms, researchers have started to focus on the concept of Blockchain interoperability. Blockchain interoperability is the ability of connecting multiple blockchain networks together, which significantly increases and solves scalability and connectivity issues in the blockchain platforms. Given the potential of blockchain interoperability and cross blockchain communication, many researchers are working on finding the optimal cross blockchain communication solution. As blockchain interoperability is emerging as an essential blockchain feature, the number of proposed blockchain interoperability solutions have been increasing within the last few years. In this paper, a survey of all the available cross blockchain communication solutions are discussed with a comparison of the proposed architectures.

Jagdeep Sidhu

While Bitcoin (Peer-to-Peer Electronic Cash) [Nak]solved the double spend problem and provided work withtimestamps on a public ledger, it has not to date extendedthe functionality of a blockchain beyond a transparent andpublic payment system. Satoshi Nakamoto's original referenceclient had a decentralized marketplace service which was latertaken out due to a lack of resources [Deva]. We continued withNakamoto's vision by creating a set of commercial-grade ser-vices supporting a wide variety of business use cases, includinga fully developed blockchain-based decentralized marketplace,secure data storage and transfer, and unique user aliases thatlink the owner to all services controlled by that alias.

Rituparna Bhattacharya, Martin White, Natalia Beloff

Almost every traveller possesses some amount of leftover foreign currency, either as actual cash or on a travel currency card, at the end of any international trip. However, the means to exchange this leftover currency, coins in particular, is largely inconvenient often leading to considerable amounts discarded or left unused. In this paper, we explore how distributed ledger technology, i.e. blockchain, could be applied to the problem of utilizing this leftover foreign currency. We portray here the drawbacks of the existing systems of foreign currency exchange and delineate the requirements of a potential mobile web application for exchanging this currency by integrating smart kiosk based systems, particularly for handling cash, with a peer-to-peer currency exchange technique based on blockchain that could help to bring such currency back into circulation efficiently.

Tong Jin, Xiang Zhang, Yirui Liu, Kai Lei

Blockchain provides a new approach for participants to maintain reliable databases in untrusted networks without centralized authorities. However, there are still many serious problems in real blockchain systems in IP network such as the lack of support for multicast and the hierarchies of status. In this paper, we design a bitcoin-like blockchain system named BlockNDN over Named Data Networking and we implement and deploy it on our cluster as well. The resulting design solves those problems in IP network. It provides completely decentralized systems and simplifies system architecture. It also improves the weak-connectivity phenomenon and decreases the broadcast overhead.

Quanqing Xu, Khin Mi Mi Aung, Yongqing Zhu, Khai Leong Yong

No abstract is available for this record.

Yuma Sakakibara, Kohei Nakamura, Hiroki Matsutani

These days, people pay attention to Blockchain, which is a main technology of cryptocurrency. Blockchain is a fault-tolerant distributed ledger that does not need an administrator. We call transfer of digital asset as a "transaction". We need to hold all transactions to use Blockchain. Therefore, the amount of Blockchain data increases as time proceeds. On the other hand, the number of Internet of Things (IoT) products has been increasing. It is difficult for IoT products to hold all Blockchain data because of their data capacity. Thus, they access Blockchain network via servers that have enough data capacity. More and more IoT products will join Blockchain network via servers, so it is useful to reduce workloads and improve throughput. In this paper, we propose caching technique using a Field Programmable Gate Array-based (FPGA) Network Interface Card (NIC) that has 10Gigabit Ethernet (10GbE) interfaces. FPGA NIC instead of the server responds to requests from IoT products if the cache hits. The proposed system can reduce server workloads. We implemented the proposed hardware cache to achieve high throughput on NetFPGA-10G board. We counted the number of requests that the Blockchain server processed at a given time and calculated throughput as evaluation. Throughput improved from 6.73 to 7.45 times when hitting the cache.

Chun-Feng Liao, Sheng-Wen Bao, Ching-Ju Cheng, Kung Chen

We can perceive the advent of smart living spaces attributed to the fast emerging of IoT (Internet of Things) technologies. By combining with the blockchain technology, many innovative business models can be brought into reality. This paper aims to report our recent progress in investigating the architectural issues for realizing blockchain-driven IoT services. In particular, we present and discuss four typical architectural styles for such services. A preliminary evaluation against different styles is also provided to compare the given styles.

Hiroki Nakashima, Mikio Aoyama

As the number of Web APIs is rapidly increasing, it is an urgent issue to discover qualified Web APIs and provide value-added services by orchestrating them. However, most of the interface descriptions of Web APIs are informal, and the Web API SLA contracts, which are a key to quality of services orchestration, require manual operations at the consumers. Meanwhile, applying the blockchain, the distributed ledger technology, to various domains beyond Fintech is attracting attention because of its fault-tolerant and anti-tampering. However, it isn't applied to Web API SLA contracts, yet. In this article, the authors propose a formal specification description of Web APIs together with its associated SLA specifications based on RDF, and an SLA contract method based on the common SLA contract platform built on the blockchain. We implemented the prototype of the SLA contract platform, and applied it to the examples for demonstrating its feasibility. Those experiences prove the feasibility of the proposed Web API SLA contract method and its supporting platform.

Thomas Lundqvist, Andreas de Blanche, H. Robert H. Andersson

Thing-to-thing payments are a key enabler in the Internet of Things (IoT) era, to ubiquitously allow for devices to pay each other for services without any human interaction. Traditional credit card-based systems are not able to handle this new paradigm, however blockchain technology is a promising payment candidate in this context. The prominent example of blockchain technology is Bitcoin, with its decentralized structure and ease of account creation. This paper presents a proof-of-concept implementation of a smart cable that connects to a smart socket and without any human interaction pays for electricity. In this paper, we identify several obstacles for the widespread use of bitcoins in thing-to-thing payments. A critical problem is the high transaction fees in the Bitcoin network when doing micro transactions. To reduce this impact, we present a single-fee micro-payment protocol that aggregates multiple smaller payments incrementally into one larger transaction needing only one transaction fee. The proof-of concept shows that trustless, autonomous, and ubiquitous thing-to-thing micro-payments is no longer a future technology.

Fabien Imbault, Marie Swiatek, Rodolphe De Beaufort, R. Plana

Energy systems are evolving towards a more decentralized model accommodate with heterogeneous but competitive energy sources and energy storage systems (ESS). This will enable peer to peer energy transactions through microgrids architectures. This paper explores the use of blockchain technology implemented on an Industrial operating system (Predix) for a use case of green certificates, demonstrated within an eco-district.

Harald Vranken

No abstract is available for this record.

Dinesh Verma, Nirmit Desai, Alun Preece, Ian Taylor

To support dynamic communities of interests in coalition operations, new architectures for efficient sharing of ISR assets are needed. The use of blockchain technology in wired business environments, such as digital currency systems, offers an interesting solution by creating a way to maintain a distributed shared ledger without requiring a single trusted authority. In this paper, we discuss how a blockchain-based system can be modified to provide a solution for dynamic asset sharing amongst coalition members, enabling the creation of a logically centralized asset management system by a seamless policy-compliant federation of different coalition systems. We discuss the use of blockchain for three different types of assets in a coalition context, showing how blockchain can offer a suitable solution for sharing assets in those environments. We also discuss the limitations in the current implementations of blockchain which need to be overcome for the technology to become more effective in a decentralized tactical edge environment.

Mayra Samaniego, Ralph Deters

Until now, most systems for Internet of Things (IoT) management, have been designed in a Cloud-centric manner, getting benefits from the unified platform that the Cloud offers. However, a Cloud-centric infrastructure mainly achieves static sensor and data streaming systems, which do not support the direct configuration management of IoT components. To address this issue, a virtualization of IoT components (Virtual Resources) is introduced at the edge of the IoT network. This research also introduces permission-based Blockchain protocols to handle the provisioning of Virtual Resources directly onto edge devices. The architecture presented by this research focuses on the use of Virtual Resources and Blockchain protocols as management tools to distribute configuration tasks towards the edge of the IoT network. Results from lab experiments demonstrate the successful deployment and communication performance (response time in milliseconds) of Virtual Resources on two edge platforms, Raspberry Pi and Edison board. This work also provides performance evaluations of two permission-based blockchain protocol approaches. The first blockchain approach is a Blockchain as a Service (BaaS) in the Cloud, Bluemix. The second blockchain approach is a private cluster hosted in a Fog network, Multichain

Vanesa Daza, Roberto Di Pietro, Ivan Klimek, Matteo Signorini

The Internet of Things is gaining momentum thanks to the provided vision of seamlessly interconnected devices. However, a unified way to discover and to interact with the surrounding smart environment is missing. As an outcome, we have been assisting to the development of heterogeneous ecosystems, where each service provider adopts its own protocol- thus preventing IoT devices from interacting when belonging to different providers. And, the same is happening again for the blockchain technology which provides a robust and trusted way to accomplish tasks -unfortunately not providing interoperability thus creating the same heterogeneous ecosystems above highlighted. In this context, the fundamental research question we address is how do we find things or services in the Internet of Things. In this paper, we propose the first IoT discovery approach which provides an answer to the above question by exploiting hierarchical and universal multi-layered blockchains. Our approach does neither define new standards nor force service providers to change their own protocol. On the contrary, it leverages the existing and publicly available information obtained from each single blockchain to have a better knowledge of the surrounding environment. The proposed approach is detailed and discussed with the support of relevant use cases.

Saravanan Raju, Sai Boddepalli, Suraj Gampa, Qiben Yan · 5 authors

Cloud-centric cognitive cellular networks utilize dynamic spectrum access and opportunistic network access technologies as a means to mitigate spectrum crunch and network demand. However, furnishing a carrier with personally identifiable information for user setup increases the risk of profiling in cognitive cellular networks, wherein users seek secondary access at various times with multiple carriers. Moreover, network access provisioning - assertion, authentication, authorization, and accounting - implemented in conventional cellular networks is inadequate in the cognitive space, as it is neither spontaneous nor scalable. In this paper, we propose a privacy-enhancing user identity management system using blockchain technology which places due importance on both anonymity and attribution, and supports end-to-end management from user assertion to usage billing. The setup enables network access using pseudonymous identities, hindering the reconstruction of a subscriber's identity. Our test results indicate that this approach diminishes access provisioning duration by up to 4x, decreases network signaling traffic by almost 40%, and enables near real-time user billing that may lead to approximately 3x reduction in payments settlement time.

Sadhu Ram Basnet, Subarna Shakya

One of the major concerns on today's Software-Defined Network (SDN) is to enhance its security. Files sharing in SDN can be made much more secured against fraudulent activities by the implementation of blockchain technology. When the privacy of network's users is increased, the reliability of system increases correspondingly. Blockchain Security over SDN (BSS) is proposed which protects privacy and availability of resources against non-trusting members. Mininet emulator is used for simulating custom SDN network topology. OpenDaylight controller is integrated with OpenStack controller. For cloud data storage, OpenStack platform is used. For testing purpose of Blockchain, Pyethereum tester tool under Ethereum platform is implemented. Serpent programming is used for creating contract in the blockchain. BSS facilitates files sharing among SDN users in distributed peer-to-peer basis using OpenStack as a cloud storage platform.

Nelisiwe Peaceness Dlamini, Mfundo Shakes Scott, Kishor Krishnan Nair

The popularity of Crypto currencies has not gone unnoticed, Bitcoin which is an electronic payment system and Internet money, is a leading crypto currency and continues to grow from being popular amongst the people who have knowledge about this technology, i.e. the developers, investors and tech-savvy enthusiasts and those that don't. If a person wants to use Bitcoin they need to have a Bitcoin wallet which stores the public and private keys used when sending and receiving bitcoins. Most of these Bitcoin wallets were developed for people who have access to technologies such as smart phones, computers and an Internet connection. This paper presents a simplified Short Message Service (SMS) system that can be used by people who do not have access to these technologies. The system was developed as a prototype and tested on a low-end mobile phone to demonstrate its capabilities. It still needs to be enhanced further to enable anyone to use it, e.g. increase the speed of transactions and SMS responses and the use of better security methods.