Visible to the public Biblio

Filters: Keyword is smart contracts  [Clear All Filters]
2021-07-08
Oktian, Yustus Eko, Lee, Sang-Gon, Lee, Hoon-Jae.  2020.  TwoChain: Leveraging Blockchain and Smart Contract for Two Factor Authentication. 2020 3rd International Seminar on Research of Information Technology and Intelligent Systems (ISRITI). :187—191.
User identity and personal information remain to be hot targets for attackers. From recent surveys, we can categorize that 65.5% of all cyberattacks in 2018 target user information. Sadly, most of the time, the system's security depends on how secure it is the implementation from the provider-side. One defense technique that the user can take part in is applying a two-factor authentication (2FA) system for their account. However, we observe that state-of-the-art 2FAs have several weaknesses and limitations. In this paper, we propose TwoChain, a blockchain-based 2FA system for web services to overcome those issues. Our implementation facilitates an alternative 2FA system that is more secure, disposable, and decentralized. Finally, we release TwoChain for public use.
2021-06-30
Solomon Doss, J. Kingsleen, Kamalakkannan, S..  2020.  IoT System Accomplishment using BlockChain in Validating and Data Security with Cloud. 2020 Fourth International Conference on I-SMAC (IoT in Social, Mobile, Analytics and Cloud) (I-SMAC). :60—64.
In a block channel IoT system, sensitive details can be leaked by means of the proof of work or address check, as data or application Validation data is applied on the blockchain. In this, the zero-knowledge evidence is applied to a smart metering system to show how to improve the anonymity of the blockchain for privacy safety without disclosing information as a public key. Within this article, a blockchain has been implemented to deter security risks such as data counterfeiting by utilizing intelligent meters. Zero-Knowledge Proof, an anonymity blockchain technology, has been implemented through block inquiry to prevent threats to security like personal information infringement. It was suggested that intelligent contracts would be used to avoid falsification of intelligent meter data and abuse of personal details.
2021-06-28
Roshan, Rishu, Matam, Rakesh, Mukherjee, Mithun, Lloret, Jaime, Tripathy, Somanath.  2020.  A secure task-offloading framework for cooperative fog computing environment. GLOBECOM 2020 - 2020 IEEE Global Communications Conference. :1–6.
Fog computing architecture allows the end-user devices of an Internet of Things (IoT) application to meet their latency and computation requirements by offloading tasks to a fog node in proximity. This fog node in turn may offload the task to a neighboring fog node or the cloud-based on an optimal node selection policy. Several such node selection policies have been proposed that facilitate the selection of an optimal node, minimizing delay and energy consumption. However, one crucial assumption of these schemes is that all the networked fog nodes are authorized part of the fog network. This assumption is not valid, especially in a cooperative fog computing environment like a smart city, where fog nodes of multiple applications cooperate to meet their latency and computation requirements. In this paper, we propose a secure task-offloading framework for a distributed fog computing environment based on smart-contracts on the blockchain. The proposed framework allows a fog-node to securely offload tasks to a neighboring fog node, even if no prior trust-relation exists. The security analysis of the proposed framework shows how non-authenticated fog nodes are prevented from taking up offloading tasks.
2021-05-20
Dua, Amit, Barpanda, Siddharth Sekhar, Kumar, Neeraj, Tanwar, Sudeep.  2020.  Trustful: A Decentralized Public Key Infrastructure and Identity Management System. 2020 IEEE Globecom Workshops GC Wkshps. :1—6.

Modern Internet TCP uses Secure Sockets Layers (SSL)/Transport Layer Security (TLS) for secure communication, which relies on Public Key Infrastructure (PKIs) to authenticate public keys. Conventional PKI is done by Certification Authorities (CAs), issuing and storing Digital Certificates, which are public keys of users with the users identity. This leads to centralization of authority with the CAs and the storage of CAs being vulnerable and imposes a security concern. There have been instances in the past where CAs have issued rogue certificates or the CAs have been hacked to issue malicious certificates. Motivated from these facts, in this paper, we propose a method (named as Trustful), which aims to build a decentralized PKI using blockchain. Blockchains provide immutable storage in a decentralized manner and allows us to write smart contracts. Ethereum blockchain can be used to build a web of trust model where users can publish attributes, validate attributes about other users by signing them and creating a trust store of users that they trust. Trustful works on the Web-of-Trust (WoT) model and allows for any entity on the network to verify attributes about any other entity through a trusted network. This provides an alternative to the conventional CA-based identity verification model. The proposed model has been implemented and tested for efficacy and known major security attacks.

Al-madani, Ali Mansour, Gaikwad, Ashok T., Mahale, Vivek, Ahmed, Zeyad A.T..  2020.  Decentralized E-voting system based on Smart Contract by using Blockchain Technology. 2020 International Conference on Smart Innovations in Design, Environment, Management, Planning and Computing (ICSIDEMPC). :176—180.

Nowadays the use of the Internet is growing; E-voting system has been used by different countries because it reduces the cost and the time which used to consumed by using traditional voting. When the voter wants to access the E-voting system through the web application, there are requirements such as a web browser and a server. The voter uses the web browser to reach to a centralized database. The use of a centralized database for the voting system has some security issues such as Data modification through the third party in the network due to the use of the central database system as well as the result of the voting is not shown in real-time. However, this paper aims to provide an E-voting system with high security by using blockchain. Blockchain provides a decentralized model that makes the network Reliable, safe, flexible, and able to support real-time services.

2021-04-27
Giannoutakis, K. M., Spathoulas, G., Filelis-Papadopoulos, C. K., Collen, A., Anagnostopoulos, M., Votis, K., Nijdam, N. A..  2020.  A Blockchain Solution for Enhancing Cybersecurity Defence of IoT. 2020 IEEE International Conference on Blockchain (Blockchain). :490—495.

The growth of IoT devices during the last decade has led to the development of smart ecosystems, such as smart homes, prone to cyberattacks. Traditional security methodologies support to some extend the requirement for preserving privacy and security of such deployments, but their centralized nature in conjunction with low computational capabilities of smart home gateways make such approaches not efficient. Last achievements on blockchain technologies allowed the use of such decentralized architectures to support cybersecurity defence mechanisms. In this work, a blockchain framework is presented to support the cybersecurity mechanisms of smart homes installations, focusing on the immutability of users and devices that constitute such environments. The proposed methodology provides also the appropriate smart contracts support for ensuring the integrity of the smart home gateway and IoT devices, as well as the dynamic and immutable management of blocked malicious IPs. The framework has been deployed on a real smart home environment demonstrating its applicability and efficiency.

Vishwakarma, L., Das, D..  2020.  BSS: Blockchain Enabled Security System for Internet of Things Applications. 2020 IEEE 19th International Symposium on Network Computing and Applications (NCA). :1—4.

In the Internet of Things (IoT), devices can interconnect and communicate autonomously, which requires devices to authenticate each other to exchange meaningful information. Otherwise, these things become vulnerable to various attacks. The conventional security protocols are not suitable for IoT applications due to the high computation and storage demand. Therefore, we proposed a blockchain-enabled secure storage and communication scheme for IoT applications, called BSS. The scheme ensures identification, authentication, and data integrity. Our scheme uses the security advantages of blockchain and helps to create safe zones (trust batch) where authenticated objects interconnect securely and do communication. A secure and robust trust mechanism is employed to build these batches, where each device has to authenticate itself before joining the trust batch. The obtained results satisfy the IoT security requirements with 60% reduced computation, storage and communication cost compared with state-of-the-art schemes. BSS also withstands various cyberattacks such as impersonation, message replay, man-in-the-middle, and botnet attacks.

Hammoud, O. R., Tarkhanov, I. A..  2020.  Blockchain-based open infrastructure for URL filtering in an Internet browser. 2020 IEEE 14th International Conference on Application of Information and Communication Technologies (AICT). :1—4.
This research is dedicated to the development of a prototype of open infrastructure for users’ internet traffic filtering on a browser level. We described the advantages of a distributed approach in comparison with current centralized solutions. Besides, we suggested a solution to define the optimum size for a URL storage block in Ethereum network. This solution may be used for the development of infrastructure of DApps applications on Ethereum network in future. The efficiency of the suggested approach is supported by several experiments.
Alniamy, A. M., Liu, H..  2020.  Blockchain-Based Secure Collaboration Platform for Sharing and Accessing Scientific Research Data. 2020 3rd International Conference on Hot Information-Centric Networking (HotICN). :34—40.
Research teams or institutions in different countries need an effective and secure online platform for collaboration and data sharing. It is essential to build such a collaboration platform with strong data security and privacy. In this paper, we propose a platform for researchers to collaborate and share their data by leveraging attribute-based access control (ABAC) and blockchain technologies. ABAC provides an access control paradigm whereby access rights are granted to users through attribute-based policies, instead of user identities and roles. Hyperledger fabric permission blockchain is used to enable a decentralized secure data sharing environment and preserves user’s privacy. The proposed platform allows researchers to fully control their data, manage access to the data at a fine-grained level, keep file updates with proof of authorship, and ensure data integrity and privacy.
2021-03-29
Gururaj, P..  2020.  Identity management using permissioned blockchain. 2020 International Conference on Mainstreaming Block Chain Implementation (ICOMBI). :1—3.

Authenticating a person's identity has always been a challenge. While attempts are being made by government agencies to address this challenge, the citizens are being exposed to a new age problem of Identity management. The sharing of photocopies of identity cards in order to prove our identity is a common sight. From score-card to Aadhar-card, the details of our identity has reached many unauthorized hands during the years. In India the identity thefts accounts for 77% [1] of the fraud cases, and the threats are trending. Programs like e-Residency by Estonia[2], Bitnation using Ethereum[3] are being devised for an efficient Identity Management. Even the US Home Land Security is funding a research with an objective of “Design information security and privacy concepts on the Blockchain to support identity management capabilities that increase security and productivity while decreasing costs and security risks for the Homeland Security Enterprise (HSE).” [4] This paper will discuss the challenges specific to India around Identity Management, and the possible solution that the Distributed ledger, hashing algorithms and smart contracts can offer. The logic of hashing the personal data, and controlling the distribution of identity using public-private keys with Blockchain technology will be discussed in this paper.

Naik, N., Jenkins, P..  2020.  uPort Open-Source Identity Management System: An Assessment of Self-Sovereign Identity and User-Centric Data Platform Built on Blockchain. 2020 IEEE International Symposium on Systems Engineering (ISSE). :1—7.

Managing identity across an ever-growing digital services landscape has become one of the most challenging tasks for security experts. Over the years, several Identity Management (IDM) systems were introduced and adopted to tackle with the growing demand of an identity. In this series, a recently emerging IDM system is Self-Sovereign Identity (SSI) which offers greater control and access to users regarding their identity. This distinctive feature of the SSI IDM system represents a major development towards the availability of sovereign identity to users. uPort is an emerging open-source identity management system providing sovereign identity to users, organisations, and other entities. As an emerging identity management system, it requires meticulous analysis of its architecture, working, operational services, efficiency, advantages and limitations. Therefore, this paper contributes towards achieving all of these objectives. Firstly, it presents the architecture and working of the uPort identity management system. Secondly, it develops a Decentralized Application (DApp) to demonstrate and evaluate its operational services and efficiency. Finally, based on the developed DApp and experimental analysis, it presents the advantages and limitations of the uPort identity management system.

2021-03-15
Hwang, S., Ryu, S..  2020.  Gap between Theory and Practice: An Empirical Study of Security Patches in Solidity. 2020 IEEE/ACM 42nd International Conference on Software Engineering (ICSE). :542–553.
Ethereum, one of the most popular blockchain platforms, provides financial transactions like payments and auctions through smart contracts. Due to the immense interest in smart contracts in academia, the research community of smart contract security has made a significant improvement recently. Researchers have reported various security vulnerabilities in smart contracts, and developed static analysis tools and verification frameworks to detect them. However, it is unclear whether such great efforts from academia has indeed enhanced the security of smart contracts in reality. To understand the security level of smart contracts in the wild, we empirically studied 55,046 real-world Ethereum smart contracts written in Solidity, the most popular programming language used by Ethereum smart contract developers. We first examined how many well-known vulnerabilities the Solidity compiler has patched, and how frequently the Solidity team publishes compiler releases. Unfortunately, we observed that many known vulnerabilities are not yet patched, and some patches are not even sufficient to avoid their target vulnerabilities. Subsequently, we investigated whether smart contract developers use the most recent compiler with vulnerabilities patched. We reported that developers of more than 98% of real-world Solidity contracts still use older compilers without vulnerability patches, and more than 25% of the contracts are potentially vulnerable due to the missing security patches. To understand actual impacts of the missing patches, we manually investigated potentially vulnerable contracts that are detected by our static analyzer and identified common mistakes by Solidity developers, which may cause serious security issues such as financial loss. We detected hundreds of vulnerable contracts and about one fourth of the vulnerable contracts are used by thousands of people. We recommend the Solidity team to make patches that resolve known vulnerabilities correctly, and developers to use the latest Solidity compiler to avoid missing security patches.
2021-03-09
Toutara, F., Spathoulas, G..  2020.  A distributed biometric authentication scheme based on blockchain. 2020 IEEE International Conference on Blockchain (Blockchain). :470–475.

Biometric authentication is the preferred authentication scheme in modern computing systems. While it offers enhanced usability, it also requires cautious handling of sensitive users' biometric templates. In this paper, a distributed scheme that eliminates the requirement for a central node that holds users' biometric templates is presented. This is replaced by an Ethereum/IPFS combination to which the templates of the users are stored in a homomorphically encrypted form. The scheme enables the biometric authentication of the users by any third party service, while the actual biometric templates of the user never leave his device in non encrypted form. Secure authentication of users in enabled, while sensitive biometric data are not exposed to anyone. Experiments show that the scheme can be applied as an authentication mechanism with minimal time overhead.

2021-03-04
Ghaffaripour, S., Miri, A..  2020.  A Decentralized, Privacy-preserving and Crowdsourcing-based Approach to Medical Research. 2020 IEEE International Conference on Systems, Man, and Cybernetics (SMC). :4510—4515.
Access to data at large scales expedites the progress of research in medical fields. Nevertheless, accessibility to patients' data faces significant challenges on regulatory, organizational and technical levels. In light of this, we present a novel approach based on the crowdsourcing paradigm to solve this data scarcity problem. Utilizing the infrastructure that blockchain provides, our decentralized platform enables researchers to solicit contributions to their well-defined research study from a large crowd of volunteers. Furthermore, to overcome the challenge of breach of privacy and mutual trust, we employed the cryptographic primitive of Zero-knowledge Argument of Knowledge (zk-SNARK). This not only allows participants to make contributions without exposing their privacy-sensitive health data, but also provides a means for a distributed network of users to verify the validity of the contributions in an efficient manner. Finally, since without an incentive mechanism in place, the crowdsourcing platform would be rendered ineffective, we incorporated smart contracts to ensure a fair reciprocal exchange of data for reward between patients and researchers.
2021-02-03
Kaneriya, J., Patel, H..  2020.  A Comparative Survey on Blockchain Based Self Sovereign Identity System. 2020 3rd International Conference on Intelligent Sustainable Systems (ICISS). :1150—1155.

The Internet has changed business, education, healthcare, banking etc. and it is the main part of technological evolution. Internet provides us a connecting world to perform our day to day life activities easily. Internet is designed in such a way that it can uniquely identify machine, not a person, on the network hence there is need to design a system that can perform entity identification on the Internet. Currently on Internet, service providers provide identity of a user with user name and password and store this information on a centralized server. These servers become honey pot for hackers to steal user’s personal identity information and service provider can utilize user identity information using data mining, artificial intelligence for economic benefits. Aim of Self sovereign identity system is to provide decentralized, user centric identity system which is controlled by identity owner that can be developed along with distributed ledger technology i.e. blockchain. In this paper, we intend to make an exhaustive study on different blockchain based self sovereign identity implementations (such as Sovrin, Uport, EverID, LifeID, Sora, SelfKey) along with its architectural components and discuss about use case of self sovereign identity.

2021-01-18
Huitzil, I., Fuentemilla, Á, Bobillo, F..  2020.  I Can Get Some Satisfaction: Fuzzy Ontologies for Partial Agreements in Blockchain Smart Contracts. 2020 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE). :1–8.
This paper proposes a novel extension of blockchain systems with fuzzy ontologies. The main advantage is to let the users have flexible restrictions, represented using fuzzy sets, and to develop smart contracts where there is a partial agreement among the involved parts. We propose a general architecture based on four fuzzy ontologies and a process to develop and run the smart contracts, based on a reduction to a well-known fuzzy ontology reasoning task (Best Satisfiability Degree). We also investigate different operators to compute Pareto-optimal solutions and implement our approach in the Ethereum blockchain.
2020-12-02
Narang, S., Byali, M., Dayama, P., Pandit, V., Narahari, Y..  2019.  Design of Trusted B2B Market Platforms using Permissioned Blockchains and Game Theory. 2019 IEEE International Conference on Blockchain and Cryptocurrency (ICBC). :385—393.

Trusted collaboration satisfying the requirements of (a) adequate transparency and (b) preservation of privacy of business sensitive information is a key factor to ensure the success and adoption of online business-to-business (B2B) collaboration platforms. Our work proposes novel ways of stringing together game theoretic modeling, blockchain technology, and cryptographic techniques to build such a platform for B2B collaboration involving enterprise buyers and sellers who may be strategic. The B2B platform builds upon three ideas. The first is to use a permissioned blockchain with smart contracts as the technical infrastructure for building the platform. Second, the above smart contracts implement deep business logic which is derived using a rigorous analysis of a repeated game model of the strategic interactions between buyers and sellers to devise strategies to induce honest behavior from buyers and sellers. Third, we present a formal framework that captures the essential requirements for secure and private B2B collaboration, and, in this direction, we develop cryptographic regulation protocols that, in conjunction with the blockchain, help implement such a framework. We believe our work is an important first step in the direction of building a platform that enables B2B collaboration among strategic and competitive agents while maximizing social welfare and addressing the privacy concerns of the agents.

Malvankar, A., Payne, J., Budhraja, K. K., Kundu, A., Chari, S., Mohania, M..  2019.  Malware Containment in Cloud. 2019 First IEEE International Conference on Trust, Privacy and Security in Intelligent Systems and Applications (TPS-ISA). :221—227.

Malware is pervasive and poses serious threats to normal operation of business processes in cloud. Cloud computing environments typically have hundreds of hosts that are connected to each other, often with high risk trust assumptions and/or protection mechanisms that are not difficult to break. Malware often exploits such weaknesses, as its immediate goal is often to spread itself to as many hosts as possible. Detecting this propagation is often difficult to address because the malware may reside in multiple components across the software or hardware stack. In this scenario, it is usually best to contain the malware to the smallest possible number of hosts, and it's also critical for system administration to resolve the issue in a timely manner. Furthermore, resolution often requires that several participants across different organizational teams scramble together to address the intrusion. In this vision paper, we define this problem in detail. We then present our vision of decentralized malware containment and the challenges and issues associated with this vision. The approach of containment involves detection and response using graph analytics coupled with a blockchain framework. We propose the use of a dominance frontier for profile nodes which must be involved in the containment process. Smart contracts are used to obtain consensus amongst the involved parties. The paper presents a basic implementation of this proposal. We have further discussed some open problems related to our vision.

2020-12-01
Tanana, D..  2019.  Decentralized Labor Record System Based on Wavelet Consensus Protocol. 2019 International Multi-Conference on Engineering, Computer and Information Sciences (SIBIRCON). :0496—0499.

The labor market involves several untrusted actors with contradicting objectives. We propose a blockchain based system for labor market, which provides benefits to all participants in terms of confidence, transparency, trust and tracking. Our system would handle employment data through new Wavelet blockchain platform. It would change the job market enabling direct agreements between parties without other participants, and providing new mechanisms for negotiating the employment conditions. Furthermore, our system would reduce the need in existing paper workflow as well as in major internet recruiting companies. The key differences of our work from other blockchain based labor record systems are usage of Wavelet blockchain platform, which features metastability, directed acyclic graph system and Turing complete smart contracts platform and introduction of human interaction inside the smart contracts logic, instead of automatic execution of contracts. The results are promising while inconclusive and we would further explore potential of blockchain solutions for labor market problems.

2020-11-16
Zhang, C., Xu, C., Xu, J., Tang, Y., Choi, B..  2019.  GEMˆ2-Tree: A Gas-Efficient Structure for Authenticated Range Queries in Blockchain. 2019 IEEE 35th International Conference on Data Engineering (ICDE). :842–853.
Blockchain technology has attracted much attention due to the great success of the cryptocurrencies. Owing to its immutability property and consensus protocol, blockchain offers a new solution for trusted storage and computation services. To scale up the services, prior research has suggested a hybrid storage architecture, where only small meta-data are stored onchain and the raw data are outsourced to off-chain storage. To protect data integrity, a cryptographic proof can be constructed online for queries over the data stored in the system. However, the previous schemes only support simple key-value queries. In this paper, we take the first step toward studying authenticated range queries in the hybrid-storage blockchain. The key challenge lies in how to design an authenticated data structure (ADS) that can be efficiently maintained by the blockchain, in which a unique gas cost model is employed. By analyzing the performance of the existing techniques, we propose a novel ADS, called GEM2-tree, which is not only gas-efficient but also effective in supporting authenticated queries. To further reduce the ADS maintenance cost without sacrificing much the query performance, we also propose an optimized structure, GEM2*-tree, by designing a two-level index structure. Theoretical analysis and empirical evaluation validate the performance of the proposed ADSs.
2020-11-09
Bose, S., Raikwar, M., Mukhopadhyay, D., Chattopadhyay, A., Lam, K..  2018.  BLIC: A Blockchain Protocol for Manufacturing and Supply Chain Management of ICS. 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). :1326–1335.
Blockchain technology has brought a huge paradigm shift in multiple industries, by integrating distributed ledger, smart contracts and consensus protocol under the same roof. Notable applications of blockchain include cryptocurrencies and large-scale multi-party transaction management systems. The latter fits very well into the domain of manufacturing and supply chain management for Integrated Circuits (IC), which, despite several advanced technologies, is vulnerable to malicious practices, such as overproduction, IP piracy and deleterious design modification to gain unfair advantages. To combat these threats, researchers have proposed several ideas like hardware metering, design obfuscation, split manufacturing and watermarking. In this paper, we show, how these issues can be complementarily dealt with using blockchain technology coupled with identity-based encryption and physical unclonable functions, for improved resilience against certain adversarial motives. As part of our proposed blockchain protocol, titled `BLIC', we propose an authentication mechanism to secure both active and passive IC transactions, and a composite consensus protocol designed for IC supply chains. We also present studies on the security, scalability, privacy and anonymity of the BLIC protocol.
2020-11-02
Ajay, K, Bharath, B, Akhil, M V, Akanksh, R, Hemavathi, P.  2018.  Intellectual Property Management Using Blockchain. 2018 3rd International Conference on Inventive Computation Technologies (ICICT). :428—430.

With the advent of blockchain technology, multiple avenues of use are being explored. The immutability and security afforded by blockchain are the key aspects of exploitation. Extending this to legal contracts involving digital intellectual properties provides a way to overcome the use of antiquated paperwork to handle digital assets.

2020-10-06
Li, Yue.  2019.  Finding Concurrency Exploits on Smart Contracts. 2019 IEEE/ACM 41st International Conference on Software Engineering: Companion Proceedings (ICSE-Companion). :144—146.

Smart contracts have been widely used on Ethereum to enable business services across various application domains. However, they are prone to different forms of security attacks due to the dynamic and non-deterministic blockchain runtime environment. In this work, we highlighted a general miner-side type of exploit, called concurrency exploit, which attacks smart contracts via generating malicious transaction sequences. Moreover, we designed a systematic algorithm to automatically detect such exploits. In our preliminary evaluation, our approach managed to identify real vulnerabilities that cannot be detected by other tools in the literature.

2020-09-28
Patsonakis, Christos, Terzi, Sofia, Moschos, Ioannis, Ioannidis, Dimosthenis, Votis, Konstantinos, Tzovaras, Dimitrios.  2019.  Permissioned Blockchains and Virtual Nodes for Reinforcing Trust Between Aggregators and Prosumers in Energy Demand Response Scenarios. 2019 IEEE International Conference on Environment and Electrical Engineering and 2019 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I CPS Europe). :1–6.
The advancement and penetration of distributed energy resources (DERs) and renewable energy sources (RES) are transforming legacy energy systems in an attempt to reduce carbon emissions and energy waste. Demand Response (DR) has been identified as a key enabler of integrating these, and other, Smart Grid technologies, while, simultaneously, ensuring grid stability and secure energy supply. The massive deployment of smart meters, IoT devices and DERs dictate the need to move to decentralized, or even localized, DR schemes in the face of the increased scale and complexity of monitoring and coordinating the actors and devices in modern smart grids. Furthermore, there is an inherent need to guarantee interoperability, due to the vast number of, e.g., hardware and software stakeholders, and, more importantly, promote trust and incentivize the participation of customers in DR schemes, if they are to be successfully deployed.In this work, we illustrate the design of an energy system that addresses all of the roadblocks that hinder the large scale deployment of DR services. Our DR framework incorporates modern Smart Grid technologies, such as fog-enabled and IoT devices, DERs and RES to, among others, automate asset handling and various time-consuming workflows. To guarantee interoperability, our system employs OpenADR, which standardizes the communication of DR signals among energy stakeholders. Our approach acknowledges the need for decentralization and employs blockchains and smart contracts to deliver a secure, privacy-preserving, tamper-resistant, auditable and reliable DR framework. Blockchains provide the infrastructure to design innovative DR schemes and incentivize active consumer participation as their aforementioned properties promote transparency and trust. In addition, we harness the power of smart contracts which allows us to design and implement fully automated contractual agreements both among involved stakeholders, as well as on a machine-to-machine basis. Smart contracts are digital agents that "live" in the blockchain and can encode, execute and enforce arbitrary agreements. To illustrate the potential and effectiveness of our smart contract-based DR framework, we present a case study that describes the exchange of DR signals and the autonomous instantiation of smart contracts among involved participants to mediate and monitor transactions, enforce contractual clauses, regulate energy supply and handle payments/penalties.
Guo, Hao, Li, Wanxin, Nejad, Mark, Shen, Chien-Chung.  2019.  Access Control for Electronic Health Records with Hybrid Blockchain-Edge Architecture. 2019 IEEE International Conference on Blockchain (Blockchain). :44–51.
The global Electronic Health Record (EHR) market is growing dramatically and expected to reach \$39.7 billions by 2022. To safe-guard security and privacy of EHR, access control is an essential mechanism for managing EHR data. This paper proposes a hybrid architecture to facilitate access control of EHR data by using both blockchain and edge node. Within the architecture, a blockchain-based controller manages identity and access control policies and serves as a tamper-proof log of access events. In addition, off-chain edge nodes store the EHR data and apply policies specified in Abbreviated Language For Authorization (ALFA) to enforce attribute-based access control on EHR data in collaboration with the blockchain-based access control logs. We evaluate the proposed hybrid architecture by utilizing Hyperledger Composer Fabric blockchain to measure the performance of executing smart contracts and ACL policies in terms of transaction processing time and response time against unauthorized data retrieval.