People often talk about the food supply chain, but in reality it isn't a chain at all. The food system today-that is, the way we get our food from farm to tablehas evolved into a complex network that is interdependent on many entities. And while there is no question that today's food system provides consumers with a more diverse, convenient, and economical source of food, it also presents new challenges. For example, in today's food system, the output from one ingredient producer could end up in thousands of products on a grocery store shelf. We saw evidence of this during the peanut butter Salmonella outbreak in 2008 and the E. coli illnesses caused by contaminated flour in 2016.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Kwame-Lante Wright, Martin Martinez, Uday Chadha, Bhaskar Krishnamachari
Edge computing has emerged as an effective offloading strategy for constrained devices. It enables low-capability devices to leverage nearby resources for assistance with computationally-intensive tasks. We envision a future where Internet of Things (IoT) devices may autonomously transact with other more powerful devices to request such offloading services. We believe blockchain-based technologies can help facilitate this process by tracking usage and managing payments. In this work we introduce SmartEdge, an Ethereum-based smart contract for edge computing and show that it is a low-cost, low-overhead tool for compute-resource management.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Internet of Things (IoT) devices proliferation is on the rise, where the number of connected devices has surpassed 7 billion devices in 2017, whereas insights foresee a number of 20-50 billion connections by year 2020. Most of those devices are deployed in heterogeneous and complex networks which imposes many challenges on the devices management functionality. Among those challenges is the identity management which pertains to how devices' identities are authenticated and verified in addition to how devices establish the means for authorizing and controlling access to data and services. Blockchain as a distributed ledger technology positions itself as a suitable candidate to address this challenge. That is mainly attributed to Blockchain's use of cryptographic identifiers, records immutability, and provenance. These features, together, provide a platform to implement the functions of IoT devices identity management that can ensure a global and unique identity for the devices, and also provide the mechanism to maintain it throughout the device life cycle. This paper presents a semi-decentralized Blockchain-based IoT identity management framework that provides features of identity creation and transfer of ownership, along with the capability of identity portability among networks visited by the devices. For validation, we describe a set of smart contracts that provide the functions of the registrar and management contracts.
Sambit Nayak, Nanjangud C. Narendra, Anshu Shukla, James Kempf
While blockchains and smart contracts are primarily known for their use as the technologies underlying cryptocurrencies like Bitcoin and Ethereum, these technologies also have applicability in other areas. In this paper, we present an application of smart contracts running on a permissioned distributed ledger (essentially a private blockchain where only credentialed participants are allowed to read and write) to managing tenant and service accounts in a cloud computing data center. The system is called Saranyu and it supports four services: identity management, authentication, authorization, and charging. Identity management and authentication are handled using client-generated public/private key pairs in the usual fashion. Authorization is handled as a contract from a grantee of service access rights to a recipient which is a tenant or other service. Charging is supported by Saranyu integration with payment gateways for payments related to service resource usage. We describe an implementation of Saranyu on top of the Quorum blockchain system. We believe the security, non-repudiation, tamper-resistance, and easy transaction history access brought by blockchain technology will increase transparency and trust in cloud tenant and service management and that the fundamentally distributed nature of the blockchain will make Saranyu an excellent match with developing distributed cloud architectures.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Olivia Choudhury, Nolan Rudolph, Issa Sylla, Noor Fairoza · 5 authors
Smart contracts are essential in implementing and automating transactions in a blockchain network. The translation of existing business rules on transactions to a smart contract is challenging and time consuming. These types of constraints are often re-used among different contracts in a given application area. Automatic generation of smart contracts can reduce the level of expertise required for, along with the time and cost incurred in, specifying them. In this paper, we provide a novel framework for auto-generating smart contracts by enabling seamless translation of constraints encoded in a knowledge representation to blockchain requirements. Our framework uses ontologies and semantic rules to encode domain-specific knowledge and then leverages the structure of abstract syntax trees to incorporate the required constraints. We successfully demonstrate the functionality and effectiveness of our method in two different applications: translating eligibility criteria for clinical trials and car rentals.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
DAO attack showed that formal verification of smart contracts is an important issue that should be addressed to prevent irreversible consequences due to design faults activation in Blockchain applications. This paper proposes a modeling method of an Ethereum application based on smart contracts, with the aim of applying a formal method, namely Model-Checking, to verify that the application implementation complies with its specification, formalized by a set of temporal logic propositions. NuSMV tool has been chosen to support this first approach. The proposed model template is shaped by three layers capturing respectively the behavior of Ethereum blockchain, the smart contracts themselves and the execution framework. The approach is illustrated by a case study coming from energy market field.
Mallikarjun Reddy Dorsala, V. N. Sastry, Chapram Sudhakar
Outsourcing a computation has been a major research area in cryptography. A delegatorDoutsources a computation to a workerW, who expects to get paid in return for delivering correct outputs. The delegator has to verify the output returned, to guard against malicious or malfunctioning worker. The worker may not trust the delegator to pay for computations performed by him. Blockchain systems like Bitcoin and Ethereum offer public verifiability of transactions generated in their networks. These transactions are of the form of a set of opcodes in Bitcoins or initiate execution of a contract in Ethereum, thus offering execution of small programs publicly. A fair protocol for verifiable computation between two parties$D$and$W$must provide the following guarantee: (1) Fast verification: The work performed to verify the correctness of output of a function is less than the work performed to compute function. (2) Pay to learn output: W obtains pay from D iff D received the correct output of the computation from W. In this work, we design two ideal functionalities$\mathcal{F}_{CRR}^{\ast}$for single worker case and$\mathcal{F}_{CCRR}^{\ast}$for multiple workers case. Existing methods do not allow Mutual revocation of deposit transaction which reduces the cost of script execution. Our ideal functionalities offer mutual revocation of the deposit transaction made byD. We show the realization of our ideal functionality$\mathcal{F}_{CRR}^{\ast}$in Bitcoin, and we also discuss fair protocols for verifiable computations of GCD of two large numbers and optimization problems. As our final work, we show a fair protocol for proof-based verifiable computing schemes.
Voice over Long Term Evolution (VoLTE) technology defines standards to deliver real-time services such as voice and video over LTE based on IP Multimedia Subsystem (IMS) networks. The security implementation in VoLTE is End-to-Access (e2a), which means that the sessions are only encrypted between the mobile terminals and the IMS network. In this paper we propose a new approach for securing End-to-End (e2e) VoLTE media based the Ethereum Blockchain. The solution consists of creating public and private keypairs for VoLTE user equipments (UEs) and storing the public keys in the Ethereum Blockchain. The media is encrypted e2e using the Secure Real Time Protocol (SRTP) protocol with a variety of session key distribution mechanisms. Results showed that the solution implementation has minimal impact on the existing IMS network, and the secure call setup time between two terminals is negligible compared to the original VoLTE setup time.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Robert Norvill, Beltrán Borja Fiz Pontiveros, Radu State, Andréa Cullen
In this paper we propose a system that moves the bytecode of an Ethereum contract creation transaction off-chain. As blockchains are append-only we present a way to help reduce the chain size and growth for Ethereum. Contract creation transaction data is replaced with hashes which identify a file in InterPlanetary File System (IPFS). Doing so reduces the size of data stored in such transactions by 93.86% in our dataset. The proposed system retains the assurance provided by blockchain and reduces network traffic under certain conditions.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
The idea to digitally facilitate contract law and business practices through computer programs has led to the notion of smart contracts. Today's most prominent smart contract ecosystem is Ethereum, a blockchain based distributed computing platform. Due to the inherent nature of blockchain based contract execution, missing low level programming abstractions, and the constant evolution of platform features and security considerations, writing correct and secure smart contracts for Ethereum is a difficult task. Based on a Multivocal Literature Research and an analysis of the gathered data based on qualitative research methods, we mined a number of design patterns providing design guidelines. We describe those patterns in detail and provide exemplary code for better illustration. Our research shows that the patterns are widely used to address application requirements and common problems. We expect generalizability of some or all of the patterns for other smart contract ecosystems, but this is outside of the scope of this study, which studied only smart contract patterns in Ethereum.
A developing field of interest for the distributed systems and applied cryptography communities is that of smart contracts: self-executing financial instruments that synchronize their state, often through a blockchain. One such smart contract system that has seen widespread practical adoption is Ethereum, which has grown to a market capacity of 100 billion USD and clears an excess of 500,000 daily transactions. Unfortunately, the rise of these technologies has been marred by a series of costly bugs and exploits. Increasingly, the Ethereum community has turned to formal methods and rigorous program analysis tools. This trend holds great promise due to the relative simplicity of smart contracts and bounded-time deterministic execution inherent to the Ethereum Virtual Machine (EVM). Here we present KEVM, an executable formal specification of the EVM's bytecode stack-based language built with the K Framework, designed to serve as a solid foundation for further formal analyses. We empirically evaluate the correctness and performance of KEVM using the official Ethereum test suite. To demonstrate the usability, several extensions of the semantics are presented. and two different-language implementations of the ERC20 Standard Token are verified against the ERC20 specification. These results are encouraging for the executable semantics approach to language prototyping and specification.
In recent years, Bitcoin is the most valuable in the cryptocurrency market. However, prices of Bitcoin have highly fluctuated which make them very difficult to predict. Hence, this research aims to discover the most efficient and highest accuracy model to predict Bitcoin prices from various machine learning algorithms. By using 1-minute interval trading data on the Bitcoin exchange website named bitstamp from January 1, 2012 to January 8, 2018, some different regression models with scikit-Iearn and Keras libraries had experimented. The best results showed that the Mean Squared Error (MSE) was as low as 0.00002 and the R-Square (R2) was as high as 99.2%.
Rachid El Bansarkhani, Matthias Geihs, Johannes Buchmann
Blockchain technology has arisen as a promising protocol to replace centralized and less efficient systems. In fact, for the first time, it is possible to achieve decentralized consensus without the need for trusted authorities, resulting in more efficient processes and saving both money and time.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Distributed Ledger Technology (DLT) allows multiple organizations to share transaction data while protecting data integrity without the need for a central authority. However, there is a strong need to protect the privacy of transactions from parties that are not stakeholders of each transaction. Since DLT is a technology for sharing replicas of the same ledger data across multiple parties, protecting confidentiality and data privacy is essentially difficult. In this paper, we first define the properties of integrity and privacy requirements and discuss the requirements in typical use cases. Finally, we review how the requirements are addressed in existing implementations.
This review focuses on the evolution of cloud computing and distributed ledger technologies (blockchains) over the last decade. Cloud computing relies mainly on a conceptually centralized service provisioning model, while blockchain technologies originate from a peer-to-peer and a completely distributed approach. Still, noteworthy commonalities between both approaches are often overlooked by researchers. Therefore, to the best of the authors knowledge, this paper reviews both domains in parallel for the first time. We conclude that both approaches have advantages and disadvantages. The advantages of centralized service provisioning approaches are often the disadvantages of distributed ledger approaches and vice versa. It is obviously an interesting question whether both approaches could be combined in a way that the advantages can be added while the disadvantages could be avoided. We derive a software stack that could build the foundation unifying the best of these two worlds and that would avoid existing shortcomings like vendor lock-in, some security problems, and inherent platform dependencies.
This article presents the top ten obstacles towards the adoption of distributed ledgers, ranging from identifying the right ledger to use for the right use case to developing scalable consensus protocols that provide some meaningful notion of public verifiability.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Existing client onboarding and Know Your Customer (KYC) processes are typically slow, expensive and often accomplished in-person. Moreover, the current identity management models in practice deprive users from having complete control over their digital identity data. Users' identity attributes are stored on multiple centralized repositories, which often follow inadequate security policies. In this paper, we take advantage of Hyperledger Indy, a public and permissioned distributed ledger technology (DLT), to develop a digital onboarding framework based on the Self-Sovereign Identity (SSI) principles. With this framework we take a step towards tackling a number of weaknesses in current KYC processes and identity management models, while addressing the requirements associated with SSI, Privacy by Design and European Union's General Data Protection Regulation (GDPR).
Distributed blockchain ledgers are on the verge of becoming a disruptive technology, profoundly impacting a wide range of industries and established applications, such as cryptocurrency, and allowing for novel use cases in both the public sector (e.g., eGovernment, eHealth, etc.) and the private sector (e.g., finance, supply chain management, etc.). Blockchains promise the ability to maintain critical information in a trustworthy repository without any centralized management. The reliability of blockchain-enabled applications is based on the innate immutability of stored data, maintained through cryptographic means, which enables blockchains to provide transparency, efficiency, auditability, trust, and security. As the technology is still in its infancy, a number of pain points must be addressed in order to make distributed ledgers more dependable, scalable, and pervasive. In this paper, we present the research landscape in distributed ledger technology (DLT). To do so, we describe a taxonomy of blockchain applications called blockchain generations. We also present the DCS properties (Decentralization, Consistency, and Scalability) as an analogy to the CAP theorem. Furthermore, we provide a general structure of the blockchain platform which decomposes the distributed ledger into six layers: Application, Modeling, Contract, System, Data, and Network. Finally, we classify research angles across three dimensions: DCS properties impacted, targeted applications, and related layers.
John R. Adler, Ryan Berryhill, Andreas Veneris, Zissis Poulos · 6 authors
The public blockchain was originally conceived to process monetary transactions in a peer-to-peer network while preventing double-spending. It has since been extended to numerous other applications including execution of programs that exist on the blockchain called "smart contracts." Smart contracts have a major limitation, namely they only operate on data that is on the blockchain. Trusted entities called oracles attest to external data in order to bring it onto the blockchain but they do so without the robust security guarantees that blockchains generally provide. This has the potential to turn oracles into centralized points-of-failure. To address this concern, this paper introduces Astraea, a decentralized oracle based on a voting game that decides the truth or falsity of propositions. Players fall into two roles: voters and certifiers. Voters play a low-risk/low-reward role that is resistant to adversarial manipulation while certifiers play a high-risk/high-reward role so they are required to play with a high degree of accuracy. This paper also presents a formal analysis of the parameters behind the system to measure the probability of an adversary with bounded funds being able to successfully manipulate the oracle's decision, that shows that the same parameters can be set to make manipulation arbitrarily difficult---a desirable feature for the system. Further, this analysis demonstrates that under those conditions a Nash equilibrium exists where all rational players are forced to behave honestly.
Blockchain, as a mechanism to decentralize services, security, and verifiability, offers a peer-to-peer system in which distributed nodes collaboratively affirm transaction provenance. In particular, blockchain enforces continuous storage of transaction history, secured via digital signature, and affirmed through consensus. In this study, we consider the recent surge in blockchain interest as an alternative to traditional centralized systems, and consider the emerging applications thereof. In particular, we assess the key techniques required for blockchain implementation, offering a primer to guide research practitioners. We first outline the blockchain framework in general, and then provide a detailed review of the component data and network structures. Additionally, we consider the breadth of applications to which blockchain has been applied, broadly implicating Internet of Things (IoT), Big Data, and Cloud and Edge computing paradigms, along with many other emerging applications. Finally, we assess the various challenges to blockchain implementation for widespread practical use, considering the security vulnerabilities to majority attacks, selfish mining, and privacy leakage, as well as performance limitations of blockchain platforms in terms of scalability and availability.
Jul 1, 2018·2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData)
Mathis Steichen, Beltran Fiz, Robert Norvill, Wazen M. Shbair · 5 authors
Large files cannot be efficiently stored on blockchains. On one hand side, the blockchain becomes bloated with data that has to be propagated within the blockchain network. On the other hand, since the blockchain is replicated on many nodes, a lot of storage space is required without serving an immediate purpose, especially if the node operator does not need to view every file that is stored on the blockchain. It furthermore leads to an increase in the price of operating blockchain nodes because more data needs to be processed, transferred and stored. IPFS is a file sharing system that can be leveraged to more efficiently store and share large files. It relies on cryptographic hashes that can easily be stored on a blockchain. Nonetheless, IPFS does not permit users to share files with selected parties. This is necessary, if sensitive or personal data needs to be shared. Therefore, this paper presents a modified version of the InterPlanetary Filesystem (IPFS) that leverages Ethereum smart contracts to provide access controlled file sharing. The smart contract is used to maintain the access control list, while the modified IPFS software enforces it. For this, it interacts with the smart contract whenever a file is uploaded, downloaded or transferred. Using an experimental setup, the impact of the access controlled IPFS is analyzed and discussed.
Luo Kan, Wei Yu, Amjad Hafiz Muhammad, Siyuan Wang · 6 authors
Blockchain is a new technology for data sharing between untrusted peers. However, it does not work well with massive transactions. Besides, there are high barriers between heterogeneous blockchain systems. In this paper, we proposed an innovative component-based framework for exchanging information across arbitrary blockchain system called interactive multiple blockchain architecture. In our architecture, a dynamic network of multi-chain is created for inter-blockchain communication. We propose the inter-blockchain connection model for routing management and messages transferring. Additionally, our proposed protocols provide transactions with atomicity and consistency in crossing-chain scene. In the end, our experiment results based on a network of private multiple blockchain systems show that the throughput is increased by a number of chains parallel running.
Privacy, facilitated by a confluence of cryptography and decentralization, is one of the primary motivations for the adoption of cryptocurrencies like Bitcoin. Alas, Bitcoins privacy promise has proven illusory, and despite growing interest in privacy-centric blockchains, most blockchain users remain susceptible to privacy attacks that exploit network-layer information and access patterns that leak as users interact with blockchains. Understanding if and how blockchain-based applications can provide strong privacy guarantees is a matter of increasing urgency. Many researchers advocate using anonymous communications networks, such as Tor, to ensure access privacy. We challenge this approach, showing the need for mechanisms through which non-anonymous users can (i) publish transactions that cannot be linked to their network addresses or to their other transactions, and (ii) fetch details of specific transactions without revealing which transactions they seek. We hope this article inspires blockchain researchers to think beyond Tor and tackle these important access privacy problems head-on.
Anamika Chauhan, Om Prakash Malviya, Madhav Verma, Tejinder Singh Mor
Bitcoin has shown great utility around the world with the drastic increase in its value and global consensus method of proof-of-work (POW). Over the years after the revolution in the digital transaction space, we are looking at major scalability issue with old POW consensus method and bitcoin peak limit of processing only 7 transactions per second. With more companies trying to adopt blockchain to modify their existing systems, blockchain working on old consensus methods and with scalability issues can't deliver the optimal solution. Specifically, with new trends like smart contracts and DAPPs, much better performance is needed to support any actual business applications. Such requirements are pushing the new platforms away from old methods of consensus and adoption of off-chain solutions. In this paper, we discuss various scalability issues with the Bitcoin and Ethereum blockchain and recent proposals like the lighting protocol, sharding, super quadratic sharding, DPoS to solve these issues. We also draw the comparison between these proposals on their ability to overcome scalability limits and highlighting major problems in these approaches. In the end, we propose our solution to suffice the scalability issue and conclude with the fact that with better scalability, blockchain has the potential to outrageously support varied domains of the industry.