Governments across the world are testing different uses of the blockchain for the delivery of their public services. Blockchain hashing-or the insertion of data in the blockchain (anchoring)-is one of the potential applications of the blockchain in this space. With this method, users can apply special scripts to add their data to blockchain transactions, ensuring both immutability and publicity. Blockchain hashing also secures the integrity of the original data stored on central governmental databases. The objective of this paper is to analyse the use of data hashing (anchoring) on the blockchain for public state-owned registries. This paper starts by analysing possible scenarios of hashing on the blockchain and assesses in which cases it may work and in which it is less likely to add value to a public administration. Second, the paper also compares this method with traditional digital signatures using PKI (Public Key Infrastructure) and discusses standardisation in each domain. Third, it also addresses issues related with concepts such as "distributed ledger technology" and "permissioned blockchains." Finally, it raises the question of whether blockchain hashing is an effective solution for electronic governance, and concludes that its value is controversial, even if it is improved by PKI and other security measures. In this regard, we claim that governments need to identify pain points in governance in the first place, and then consider the trade-offs of the blockchain as a potential solution versus other alternatives.
Thomas Hepp, Fabian Spaeh, Alexander Schoenhals, Philip Ehret · 5 authors
Traditional public key infrastructures (PKIs), in particular, X.509 and PGP, is plagued by security and usability issues. As reoccurring incidents show, these are not only of theoretical nature but allow attackers to inflict severe damage. Emerging blockchain technology allows for advances in this area, facilitating a trustless immutable ledger with fast consensus. There have been numerous proposals for utilization of the blockchain in the area of PKI, either as extensions upon existing methods or independent solutions. In this paper, we first study traditional PKI, then proceed with novel approaches, showing how they can improve upon recent issues. We provide a comprehensive evaluation, finding that independent blockchain-based solutions are preferable in the future, mainly due to their stronger security. However, global adoption of these yet requires advances in blockchain development, e.g., concerning scalability.
Kota Dharma Teja, M Shravani, Chintarlapallireddy Yaswanth Simha, Manjunath R Kounte
Voting is the primary factor to change the country's future. The manual voting got replaced with the electronic machines called Electronic Voting Machines(EVM). Even after replacement, the issues continue to trouble voters. Issues like missing names in voter list, misplaced votes and so on. That is why we suggest a decentralised system to be integrated with the voting system to make it error-free. One of those decentralised systems are blockchain technology. Our project is developed on Ethereum platform using solidity language. Estonia, the blockchain country uses blockchain for almost all services. The voting procedure is presented in the paper as a case study. We summarise the tools used for the project along with its features. We also appraise the working of the our project in the further sections. Finally, we include the source smart contract code in the appendix. This project open up many possibilities to secure the voting system and help for the welfare of the nations.
In a democratic country like India (which is the largest democracy in the world), Voting plays a major role in the selection of government officials as well as showing our opinion how the governing body to be formed. Time to time, researches are conducted in order to tackle the difficulties in the centralized voting system to make it more anonymous, reliable and secure while preventing any kind of frauding. Even though the use of e-voting through the electronic medium, we have to face well-known problems of maintenance and fraud. Currently, various researches are conducting in-order to make secure and reliable voting system while tackling issues of anonymity and security. Through Decentralized System, focus is drifting towards making Voting Process simple, secure and anonymity in the hand of the public. This paper presents a literature review on the papers and the techniques used to tackle voting challenges.
Internet Traffic Analysis and Secure E-voting
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Security and Privacy are some of the important aspects to be considered in the large-scale deployment of Internet of Things (IoT) systems. Due to the large number of IoT devices and the different administrative domains in which they operate, traditional approaches involving a Centralized server for managing Authorizations will not be scalable or efficient. In this paper, we propose a Decentralized Capability-Based Access Control framework using IOTA (DCACI); IOTA is an open-source distributed ledger that enables fee-less micro transactions for the IoT. The DCACI framework enables complete privacy and integrity of the Capability tokens using IOTA's Masked Authenticated Messaging (MAM) technology. It enables device owners and users to Grant, Update, Delegate and Revoke the capability tokens. The proposed DCACI framework has been implemented as a proof-of-concept on a resource constrained machine; the results indicate that it is capable of scaling up to large-scale infrastructure such as a Smart City, having millions of IoT devices.
Decentralized application users may face unexpected situations that the smart contract implementing the application should handle, but cannot, because the smart contract cannot be modified once it is deployed. Therefore, we need 'stronger' smart contracts with flexible structures that are resilient in such unexpected situations. In this paper, we propose a generic mechanism to strengthen smart contracts and handle possible unexpected situations. Given a smart contract, this mechanism automatically generates an action list which offers actions as interfaces to change parameters of smart contracts and a voting system that utilizes a limited voter group randomly chosen from the peers. Each action in the action list can change a corresponding parameter of smart contracts. The actions, when approved by the majority, are executed to change the parameters. When users face unexpected situations in a transaction, they choose some actions as the solution and pass them to the voting system. Since a smart contract has finite parameters, there are finite actions. By arranging and combining these actions, our mechanism offers solutions that can handle wide-ranging unexpected situations. Also, to execute a solution, the majority of voters need to approve it, thus not violating the protocol of the original smart contract. Voters are rewarded based on quadratic rules for peer prediction, which makes telling true preferences the only way to maximize rewards. Using machine learning, we predict users' preferences based on the voting records. The predictions are provided as default values for future votes to avoid users' need to vote manually each time.
Bitcoin is a decentralized digital currency introduced in 2008 and launched in 2009. Bitcoin provides a way to transact without any trusted intermediary, but its privacy guarantees are questionable, and multiple deanonymization attacks have been proposed. Cryptocurrency privacy research has been mostly focused on blockchain analysis, i.e., extracting information from the transaction graph. We focus on another vector for privacy attacks: network analysis. We describe the message propagation mechanics in Bitcoin and propose a novel technique for transaction clustering based on network traffic analysis. We show that timings of transaction messages leak information about their origin, which can be exploited by a well connected adversarial node. We implement and evaluate our method in the Bitcoin testnet with a high level of accuracy, deanonymizing our own transactions issued from a desktop wallet (Bitcoin Core) and from a mobile (Mycelium) wallet. Compared to existing approaches, we leverage the propagation information from multiple peers, which allows us to overcome an anti-deanonymization technique (“diffusion”) used in Bitcoin.
Blockchain teknolojisi, resmi kurumların katkısı olmadan bir ağa bağlı bilgisayarlar aracılığı ile çeşitli onaylama ve doğrulama işlemlerinin gerçekleştirildiği bir sistemdir. 21. yy’da ortaya çıkan blockchain teknolojisi ve kripto paraların hızla yatırım aracına dönüştüğü görülmektedir. Bu çalışmada blockchain teknolojisinin kullanımı sonucu ortaya çıkan kripto paralar, paranın tarihinden yola çıkılarak incelenmeye çalışılmıştır. Kripto paralar sahip olduğu gücü insanların güveninden alırken, geleneksel para gücünü kendisini piyasaya süren devletten almaktadır. Bu çalışmada kripto paraların güçlü ve zayıf yönleri anlatılarak gelecekte geleneksel para birimi gibi kullanılıp kullanılamayacağı incelenmiştir. Kripto paraların bir para birimi olmaktan çok bir yatırım aracı olarak kullanıldığı görülmektedir. İnsanların bu paralara güveni devam ettiği sürece kripto paraların varlığını koruyacağı, değerinde artış ve azalışlar olacağı gözlemlenmiş, güvenin yok olması durumunda ise etkinliklerini devam ettiremeyeceği tespit edilmiştir.
Summary Proof of stake (PoS) protocols rely on voting mechanisms to reach consensus on the current state. If an enhanced majority of staking nodes, also called validators , agree on a proposed block, then this block is appended to the blockchain. Yet these protocols remain vulnerable to faults caused by validators who abstain either accidentally or maliciously. To protect against such faults while retaining the PoS selection and reward allocation schemes, we study weighted voting in validator committees. We formalize the block creation process and introduce validators' voting profiles which we update by a multiplicative weights algorithm relative to validators' voting behavior and aggregate blockchain rewards. Using this framework, we leverage weighted majority voting rules that optimize collective decision making to show, both numerically and analytically, that the consensus mechanism is more robust if validators' votes are appropriately scaled. We raise potential issues and limitations of weighted voting in trustless, decentralized networks and relate our results to the design of current PoS protocols.
In this paper we address the issue of identity and access control within\nshared permissioned blockchains. We propose the ChainAchor system that provides\nanonymous but verifiable identities for entities on the blockchain. ChainAchor\nalso provides access control to entities seeking to submit transactions to the\nblockchain to read/verify transactions on the the permissioned blockchain.\nConsensus nodes enforce access control to the shared permissioned blockchain by\na simple look-up to a (read-only) list of anonymous members' public-keys.\nChainAnchor also provides unlinkability of transactions belonging to an entity\non the blockchain. This allows for an entity to optionally disclose their\nidentity when a transaction is called into question (e.g. regulatory or\ncompliance requirements), but without affecting the anonymity and unlinkability\nof their remaining transactions.\n
Software Defined Networking (SDN) is being extensively adopted by researchers and enterprise networks due to its feature of decoupling data and control planes from network device which enables them to implement new networking ideas. Communication between data and control planes faces various security issues where many users in data plane approach controller device in control plane to gain networking policies. In this paper, we proposed an efficient Zero-knowledge proof based identification scheme for securing SDN controller during data and control plane communication. This scheme ensures that only users who prove their knowledge about secrecy without revealing actual secret or any other information about it can communicate with controller. The computation cost was calculated to validate efficiency of the proposed work and compared with scheme that works in the basis of Kerberos authentication protocol.
The revolution in the system of records has reached a great extent and paves a way for a powerful technology known as blockchain for storing data and performing transactional operations in a decentralized network. Blockchain was first developed to serve as a public transaction ledger for the cryptocurrency named “Bitcoin”. Later, One such application is the online balloting scheme. A ballot is a device that is used to cast the votes in an election. In ballot based voting, still there is no system to avoid proxy casting and recasting. We do not have any technology to view our casted votes. In the electronic voting system based on Blockchain, addresses some of the limitations in the existing systems and labels some of the issues of e-voting. The idea in blockchain enabled balloting scheme is to integrate Aadhaar card and Mobile number of the people using which the OTP is generated and then the voter is allowed to cast their vote. Ethereum is an open source blockchain based technology that uses both private blockchain and remix platform and it acts as a tool in storing the data. The user can cast their votes from anywhere (nearby booth) and the corresponding contestant are notified to the users based on their constituency and candidate promises. If NOTA votes crossed above 50%, then all the candidates are disqualified and are permitted to contest for the next election. If any of the citizen do not poll their vote, then a warning message will be sent to the respective person. They should provide a valid reason for not voting within a period of 6 months, if the reason is invalid then necessary action will be taken by the government. If a member of citizen wants to view his/her voting status then they can view it by entering their aadhar number and the block number that is sent to them through the mobile app. The implementation of this system addresses most of the issues faced in the balloting scheme and is used to avoid proxy casting and recasting and is also used to achieve above 95% of the vote.
Linh Vo-Cao- Thuy, Khoi Cao-Minh, Chuong Dang-Le-Bao, Tuan Anh Nguyen
Blockchain, which is the underlying technology of the first cryptocurrency Bitcoin, has drawn a lot of global attention in recent years. Its notable characteristics of the distributed ledger, trustless system, and immutability not only makes it a disruptive innovation in the electronic payment industry but also potential solutions for other areas that require trust establishment. Electronic voting (E-voting) scheme is a use-case where all attributes of blockchain can offer a mechanism for an open, fair and universally verifiable electoral process. In this paper, we review the requirements and then propose Votereum, an E-voting system that utilizes the blockchain technology. The proposed system is empowered by Ethereum platform, including one server manages the entire system and the other handles all blockchain-related requests. The implementation is also deployed to Rinkeby testing network for evaluation on the feasibility and discussion on some security concerns, which are mentioned in the conclusion of this paper.
2 source records
Internet Traffic Analysis and Secure E-voting
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
R. Aroul Canessane, N. Srinivasan, Abinash Beuria, Ashwini Kumar Singh · 5 authors
The concept of blockchain without a doubt is a revolutionary concept. It is the underlying Technology behind bitcoin and many more cryptocurrencies. Although the people's focus being only at blockchain as cryptocurrencies in everyday services to do payments online without the interference of a third party will try to replace the current method of cash which is a really slow and ancient method. Blockchain is a zero trust network and this makes it a very powerful tool for various services provided that people are ready to believe and invest in it. In the Ethereum world, the blockchain runs on smart contracts which are self-executing applications that come at a cost of security. This zero-trust network is capable of replacing many of the debated process or activities in our day to day life. One of our biggest concerns is an E-voting system which must be secure. Blockchain being an immutable and append only ledger will not allow for any tampering while also being fully transparent. In this paper, we have implemented and tested a sample e-voting app running as a smart contract for ethereum network using E-Wallets. After an election is held, eventually, the ethereum blockchain will hold the records of ballots and voters thus giving us a clear and trusty network where mishandling is to a minimum.
We describe the design and implementation of GNU Taler, an electronic payment system based on an extension of Chaumian online e-cash with efficient change. In addition to anonymity for customers, it provides the novel notion of income transparency, which guarantees that merchants can reliably receive a payment from an untrusted payer only when their income from the payment is visible to tax authorities. Income transparency is achieved by the introduction of a refresh protocol, which gives anonymous change for a partially spent coin without introducing a tax evasion loophole. In addition to income transparency, the refresh protocol can be used to implement Camenisch-style atomic swaps, and to preserve anonymity in the presence of protocol aborts and crash faults with data loss by participants. Furthermore, we show the provable security of our income-transparent anonymous e-cash, which, in addition to the usual anonymity and unforgeability proper- ties of e-cash, also formally models conservation of funds and income transparency. Our implementation of GNU Taler is usable by non-expert users and integrates with the modern Web architecture. Our payment platform addresses a range of practical issues, such as tipping customers, providing refunds, integrating with banks and know-your-customer (KYC) checks, as well as Web platform security and reliability requirements. On a single machine, we achieve transaction rates that rival those of global, commercial credit card processors. We increase the robustness of the exchange—the component that keeps bank money in escrow in exchange for e-cash—by adding an auditor component, which verifies the correct operation of the system and allows to detect a compromise or misbehavior of the exchange early. Just like bank accounts have reason to exist besides bank notes, e-cash only serves as part of a whole payment system stack. Distributed ledgers have recently gained immense popularity as potential replacement for parts of the traditional financial industry. While cryptocurrencies based on proof-of-work such as Bitcoin have yet to scale to be useful as a replacement for established payment systems, other more efficient systems based on Blockchains with more classical consensus algorithms might still have promising applications in the financial industry. We design, implement and analyze the performance of Byzantine Set Union Consensus (BSC), a Byzantine consensus protocol that agrees on a (super-)set of elements at once, instead of sequentially agreeing on the individual elements of a set. While BSC is interesting in itself, it can also be used as a building block for permissioned Blockchains, where—just like in Nakamoto-style consensus—whole blocks of transactions are agreed upon at once, increasing the transaction rate.
The Internet of Things (IoT) is experiencing explosive growth and has gained extensive attention from academia and industry in recent years. Most of the existing IoT infrastructures are centralized, in which the presence of a cloud server is mandatory. However, centralized frameworks suffer from the issues of unscalability and single-point-of-failure. Consequently, decentralized IoT has been proposed by taking advantage of the emerging technology of Blockchain. Voting systems are widely adopted in IoT, such as a leader election in wireless sensor networks. Self-tallying voting systems are alternatives to traditional centralized voting systems in decentralized IoT since the traditional ones are not suitable for such scenarios. Unfortunately, self-tallying voting systems inherently suffer from fairness issues, such as adaptive and abortive issues caused by malicious voters. In this paper, we introduce a framework of self-tallying systems in decentralized IoT based on Blockchain. We propose a concrete construction and prove the proposed system satisfies all the security requirements including fairness, dispute-freeness and maximal ballot secrecy. The implementations on mobile phones demonstrate the practicability of our system.
Muhammad Saad, Victor Cook, Lan N. Nguyen, My T. Thai · 5 authors
In this paper, we explore the partitioning attacks on the Bitcoin network, which is shown to exhibit spatial bias, and temporal and logical diversity. Through data-driven study we highlight: 1) the centralization of Bitcoin nodes across autonomous systems, indicating the possibility of BGP attacks, 2)the non-uniform consensus among nodes, that can be exploited to partition the network, and 3)the diversity in the Bitcoin software usage that can lead to privacy attacks. Atop the prior work, which focused on spatial partitioning, our work extends the analysis of the Bitcoin network to understand the temporal and logical effects on the robustness of the Bitcoin network.
The Ethereum block chain as a decentralized platform is so successful that many applications deployed on it. However, for the inherent transparency properties and the lack of privacy, deploying a financial application on top of it is always a challenge. In this paper, we tackle this challenge and propose an anonymous sealed-bid auction protocol based on time-released encryption atop Consortium Block chain. We adopt a strict digital certificate-based identity mechanism of the consortium block chain to permit legitimate participants, and utilize the blind signature based on elliptic curve technology to allowing anonymous participation. Moreover, a timed release public key encryption algorithm is adopted to encrypt bids and prevent auctioneer from colluding with bidders. This is completely different from the method (zero-knowledge proof) used in other papers to prevent collusion between auctioneer and bidder. We provide a specific analysis of our protocol, which shows that our protocol meets anonymity and applicability.
Public key infrastructures (PKIs) are one of the main building blocks for securing communications over the Internet. Currently, PKIs are under the control of centralized authorities, which is problematic as evidenced by numerous incidents where they have been compromised. The distributed, fault tolerant log of transactions provided by blockchains and more recently, smart contract platforms, constitutes a powerful tool for the decentralization of PKIs. To verify the validity of identity records, blockchain-based identity systems store on chain either all identity records, or, a small (or even constant) sized amount of data for verifying identity records stored off chain. However, as most of these systems have never been implemented, there is little information regarding the practical implications of each design's tradeoffs. In this work, we first implement and evaluate the only provably secure, smart contract based PKI of Patsonakis et al. on top of Ethereum. This construction incurs constant-sized storage at the expense of computational complexity. To explore this tradeoff, we propose and implement a second construction which, eliminates the need for trusted setup, preserves the security properties of Patsonakis et al. and, as illustrated through our evaluation, is the only version with constant-sized state that can be deployed on the live chain of Ethereum. Furthermore, we compare these two systems with the simple approach of most prior works, e.g., the Ethereum Name Service, where all identity records are stored on the smart contract's state, to illustrate several shortcomings of Ethereum and its cost model. We propose several modifications for fine tuning the model, which would be useful to be considered for any smart contract platform like Ethereum so that it reaches its full potential to support arbitrary distributed applications.
Recently, blockchain techniques have been widely used in finance, e-commerce and sharing economy, owing to its decentralization, openness and permission-less properties. In cybersecurity, a blockchain-based framework Sapiens Chain is proposed, which aims to provide decentralized and trustable cybersecurity services while protecting the privacy of the anonymous users. However, how to select an optimal service provider in Sapiens Chain remains challenging. In this paper, we tackle the novel problem of scheduling nodes in Sapiens Chain, which covers and rewards the nodes based on their performance with the history of providing cybersecurity services, and thus attracting more and more users to anticipate cybersecurity services. Under the scheduling algorithm, we propose to select nodes for different tasks by unifying the interest of each user, such as the bandwidth, the computing resource, and the activation degree. The experimental results demonstrate the efficiency and effectiveness of our method.
Day to day revolutionizing technology is coming up with their positive impacts on our social life. And this all-time globally connected network enables us to access variety of resources easily. One such revolution is Blockchain. With its special characteristics of immutability and decentralized architecture, many services are shifting towards it. One potential application of blockchain can be found in e-voting schemes. It has been a challenge since a long time for building an e-voting system which satisfies all legal requirements of legislators. Distributed ledger technologies can offer infinite range of applications. This paper discusses various e-voting system frameworks conceptualized by different teams. Blockchain will bring its benefits on e-voting systems including immutability of votes, security of system, real-time validation and updation of count of votes in global ledger with not depending upon number of nodes in the network.
Internet Traffic Analysis and Secure E-voting
Advanced Steganography and Watermarking Techniques