Lukas Mastilak, Pavol Helebrandt, Marek Galinski, Ivan Kotuliak
The whole Internet consists of thousands of autonomous systems that transfer data with one another. The BGP plays a significant role in routing, but its behaviour is essentially naive, trusting neighbours without authenticating advertised IP prefixes. This is the main reason why BGP endures various path manipulation attacks. Recently, conventional methods for securing BGP have been implemented, i.e., BGPSec with RPKI. However, these approaches are centralised with a single point of failure that may be compromised, invalidating the whole security mechanism. There have been multiple decentralised projects dealing with various mechanisms, mostly built on Ethereum and blockchain networks. Some with ambition to strengthen existing centralised mechanisms, others to replace them. In this article, we present the first comprehensive survey on blockchain solutions to enforce BGP security, with complex explanations of their contributions and a comparison with different aspects. We explain how blockchain technology can provide an alternative to prevent the false origin of IP prefixes or hijacking AS paths. Moreover, we describe new blockchain-based attacks that BGP would face after the inclusion of blockchain into the inter-domain routing. Finally, we answer the defined research questions and discuss the potential open issues for further study.
The blockchain specifications distributed ledger, traceability, immutability provide a secure high-speed voting system. Data stored on the blockchain cannot be traced back, edit or deleted due to which transparent and high-performance capabilities are inherent to the network. But as the information of the e-voting system increases storage space and processing cost also increases due to an increase in delay. This delay increases as the comparison of hash value with the existing hash value for uniqueness. Apart from the uniqueness of hash designer also required initial 8 bytes of hash to be zeros. In this paper, we propose the multiobjective genetic algorithm-based creation of a side-chain to enhance the scalability and performance of the blockchain-based e-voting system. We compare the storage cost and the processing cost of the state of the art models with the proposed model. our experiments yielded observations on the scalability and the performance of the blockchain-based e-voting system.
Internet Traffic Analysis and Secure E-voting
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Rajasekhar Chaganti, Bharat Bhushan, Vinayakumar Ravi
With the proliferation of new technologies such as Internet of Things (IOT) and Software-Defined Networking(SDN) in the recent years, the distributed denial of service (DDoS)attack vector has broadened and opened new opportunities for more sophisticated DDoS attacks on the targeted victims. The new attack vector includes unsecured and vulnerable IoT devices connected to the internet, denial of service vulnerabilities like southbound channel saturation in the SDN architecture. Given the high-volume and pervasive nature of these attacks, it is beneficial for stakeholders to collaborate in detecting and mitigating the denial of service attacks in a timely manner. The blockchain technology is considered to improve the security aspects owing to the decentralized design, secured distributed storage and privacy. A thorough exploration and classification of blockchain techniques used for DDoS attack mitigation is not explored in the prior art. This paper reviews and categorizes the existed state-of-the-art DDoS mitigation solutions based on blockchain technology. The DDoS mitigation techniques are classified based on the solution deployment location i.e. network based, near attacker location, near victim location and hybrid solutions in the network architecture with emphasis on the IoT and SDN architectures. Additionally, based on our study, the research challenges and future directions to implement the blockchain based DDoS mitigation solutions are discussed. We believe that this paper could serve as a starting point and reference resource for future researchers working on denial of service attacks detection and mitigation using blockchain technology.
Abhishek Phadke, F. Antonio Medrano, Stanislav Ustymenko
Since its inception in 2008, blockchain technology continues to gain prominence and impact. Beyond initial applications in digital currency, token systems, and smart contracts, blockchains have gained use in many varied fields including health care records, education, and food suppy chains. Among the most promising of these applications is e-government. Distributed secure digital ledgers with peer-to-peer architecture implemented on blockchain promise to address scalability, trust, cybersecurity, interoperability, and performance issues that often plague electronic government initiatives. This work is aimed at exploring applications of blockchain in the e-government domain. We provide an overview of the advantages and obstacles of blockchain e-government implementation. Characteristic use cases, including e-voting, finance, and energy markets are explored. By analyzing existing literature, we determine that energy utilities, identity management, transparency, and finance/tax services are major research areas in blockchain-based e-government. General process workflows of primary applications of blockchain are described. This study lays the groundwork for pursuing a common framework capable of integrating these services.
Xiaohong Zhang, Zilong Song, Ata Jahangir Moshayedi, IEEE Member
Abstract Aiming at the data authenticity and storage problems in the current coordinated scheduling of virtual power plants, as well as the opaque information and high transaction costs, a dual blockchains security mechanism is proposed to solve above problems. In the process of security scheduling, a hybrid attribute proxy re-encryption algorithm based on ciphertext strategy is designed. The algorithm is composed of an identity encryption algorithm and an attribute proxy re-encryption algorithm with ciphertext strategy. Combining blockchain, tamper-proof smart metering equipment can effectively solve data authenticity and confidentiality in the information transmission process of distributed energy. In the research process of the trading mechanism, a continuous double auction mechanism based on reputation is proposed. In order to create a favorable trading atmosphere, reputation-based market segmentation mechanisms are integrated, and participants are divided according to reputation value. Depending on the properties of the stored information, they are divided into the private blockchain (with coordination scheduling information) and the consortium blockchain (with transaction information). The system analysis shows the reliability of the dual blockchains architecture. The communication and calculation costs of the proxy re-encryption algorithm verify the practicability of the proposed scheme. The case analysis of the auction mechanism declares that the mechanism can operate effective in the electricity trading market.
Cryptocurrency systems can be subject to deanonimization attacks by exploiting the network-level communication on their peer-to-peer network. Adversaries who control a set of colluding node(s) within the peer-to-peer network can observe transactions being exchanged and infer the parties involved. Thus, various network anonymity schemes have been proposed to mitigate this problem, with some solutions providing theoretical anonymity guarantees. In this work, we model such peer-to-peer network anonymity solutions and evaluate their anonymity guarantees. To do so, we propose a novel framework that uses Bayesian inference to obtain the probability distributions linking transactions to their possible originators. We characterize transaction anonymity with those distributions, using entropy as metric of adversarial uncertainty on the originator's identity. In particular, we model Dandelion, Dandelion++ and Lightning Network. We study different configurations and demonstrate that none of them offers acceptable anonymity to their users. For instance, our analysis reveals that in the widely deployed Lightning Network, with 1% strategically chosen colluding nodes the adversary can uniquely determine the originator for about 50% of the total transactions in the network. In Dandelion, an adversary that controls 15% of the nodes has on average uncertainty among only 8 possible originators. Moreover, we observe that due to the way Dandelion and Dandelion++ are designed, increasing the network size does not correspond to an increase in the anonymity set of potential originators. Alarmingly, our longitudinal analysis of Lightning Network reveals rather an inverse trend -- with the growth of the network the overall anonymity decreases.
Voting is arguably the most important as well as elementary right in democracy that has existed for the past hundreds of years; it has taken place in the context of a large- and small-scale community. The process transitioned from paper ballots to electronic voting machines (EVM) in the late 20th century, but even with all the advancement, transparency in the election process remained the same. Blockchain technology came in existence in 2008 with the introduction of Bitcoin by Satoshi Nakamoto, and in the last decade we saw enormous growth in development and execution of this technology in various fields e-voting is one of them, blockchain-based e-voting system has potential to improve the election process if utilized to its potential. Blockchain can eliminate the need to print ballot paper as it is secure, immutable and convenient to voters and can make elections more transparent.
Zero-knowledge proof (ZKP) mixers are one of the most widely-used blockchain privacy solutions, operating on top of smart contract-enabled blockchains. We find that ZKP mixers are tightly intertwined with the growing number of Decentralized Finance (DeFi) attacks and Blockchain Extractable Value (BEV) extractions. Through coin flow tracing, we discover that 205 blockchain attackers and 2,595 BEV extractors leverage mixers as their source of funds, while depositing a total attack revenue of 412.87M USD. Moreover, the US OFAC sanctions against the largest ZKP mixer, Tornado.Cash, have reduced the mixer's daily deposits by more than 80%. Further, ZKP mixers advertise their level of privacy through a so-called anonymity set size, which similarly to k-anonymity allows a user to hide among a set of k other users. Through empirical measurements, we, however, find that these anonymity set claims are mostly inaccurate. For the most popular mixers on Ethereum (ETH) and Binance Smart Chain (BSC), we show how to reduce the anonymity set size on average by 27.34% and 46.02% respectively. Our empirical evidence is also the first to suggest a differing privacy-predilection of users on ETH and BSC. State-of-the-art ZKP mixers are moreover interwoven with the DeFi ecosystem by offering anonymity mining (AM) incentives, i.e., users receive monetary rewards for mixing coins. However, contrary to the claims of related work, we find that AM does not necessarily improve the quality of a mixer's anonymity set. Our findings indicate that AM attracts privacy-ignorant users, who then do not contribute to improving the privacy of other mixer users.
Ertem Nusret Tas, David Tse, Fisher Yu, Sreeram Kannan
Bitcoin is the most secure blockchain in the world, supported by the immense hash power of its Proof-of-Work miners, but consumes huge amount of energy. Proof-of-Stake chains are energy-efficient, have fast finality and accountability, but face several fundamental security issues: susceptibility to non-slashable long-range safety attacks, non-slashable transaction censorship and stalling attacks and difficulty to bootstrap new PoS chains from low token valuation. We propose Babylon, a blockchain platform which combines the best of both worlds by reusing the immense Bitcoin hash power to enhance the security of PoS chains. Babylon provides a data-available timestamping service, securing PoS chains by allowing them to timestamp data-available block checkpoints, fraud proofs and censored transactions on Babylon. Babylon miners merge mine with Bitcoin and thus the platform has zero additional energy cost. The security of a Babylon-enhanced PoS protocol is formalized by a cryptoeconomic security theorem which shows slashable safety and liveness guarantees.
<div>Abstract—Despite the various advantages inherent in the use of blockchain technology, blockchain application platforms are characterized by bottlenecks, latency, energy inefficiency, time inefficiency, low transaction throughput, vulnerability to 51% attacks, and a lack of fairness in the sharing of mining proceeds. These challenges are currently affecting the performance of this technology, hindering its rapid development and adoption for real-time applications such as Electronic Voting Applications (EVAs). It is well known that the consensus mechanism responsible for the security and consistency features of a blockchain, is also responsible for most of the above challenges.</div><div>In this paper, a new consensus mechanism, Proof of Vote (PoV) is proposed, a lightweight consensus mechanism specifically adapted for EVA, as a replacement for the heavyweight Proof of Work (PoW) consensus algorithm. We use the Ethereum blockchain as a decentralized application platform, in which we develop a decentralized electronic voting application (ADEVA), replacing the Ethereum PoW consensus algorithm with the proposed PoV consensus algorithm. Thus we implemented ADEVA with PoV and compared it to the two major consensus mechanisms: Proof of work (PoW) and Proof of Stake (PoS). We found that PoV enhanced the performance of ADEVA over and above that achieved using PoW and PoS. The low resource utilization and high transaction throughput of ADEVA with PoV makes it a scalable solution for real-world EVAs.</div>
Blockchain systems come with a promise of decentralization that often stumbles on a roadblock when key decisions about modifying the software codebase need to be made. This is attested by the fact that both of the two major cryptocurrencies, Bitcoin and Ethereum, have undergone hard forks that resulted in the creation of alternative systems, creating confusion and opportunities for fraudulent activities. These events, and numerous others, underscore the importance of Blockchain governance, namely the set of processes that blockchain platforms utilize in order to perform decision-making and converge to a widely accepted direction for the system to evolve. While a rich topic of study in other areas, governance of blockchain platforms is lacking a well established set of methods and practices that are adopted industry wide. This makes the topic of blockchain governance a fertile domain for a thorough systematization that we undertake in this work. We start by distilling a comprehensive array of properties for sound governance systems drawn from academic sources as well as grey literature of election systems and blockchain white papers. These are divided into seven categories, confidentiality, verifiability, accountability, sustainability, Pareto efficiency, suffrage and liveness that capture the whole spectrum of desiderata of governance systems. We proceed to classify ten well-documented blockchain systems. While all properties are satisfied, even partially, by at least one system, no system that satisfies most of them. Our work lays out a foundation for assessing blockchain governance processes. While it highlights shortcomings and deficiencies in currently deployed systems, it can also be a catalyst for improving these processes to the highest possible standard with appropriate trade-offs, something direly needed for blockchain platforms to operate effectively in the long term.
Mike Wu, Will McTighe, Kaili Wang, István András Seres · 12 authors
A common misconception among blockchain users is that pseudonymity guarantees privacy. The reality is almost the opposite. Every transaction one makes is recorded on a public ledger and reveals information about one's identity. Mixers, such as Tornado Cash, were developed to preserve privacy through "mixing" transactions with those of others in an anonymity pool, making it harder to link deposits and withdrawals from the pool. Unfortunately, it is still possible to reveal information about those in the anonymity pool if users are not careful. We introduce Tutela, an application built on expert heuristics to report the true anonymity of an Ethereum address. In particular, Tutela has three functionalities: first, it clusters together Ethereum addresses based on interaction history such that for an Ethereum address, we can identify other addresses likely owned by the same entity; second, it shows Ethereum users their potentially compromised transactions; third, Tutela computes the true size of the anonymity pool of each Tornado Cash mixer by excluding potentially compromised transactions. A public implementation of Tutela can be found at https://github.com/TutelaLabs/tutela-app. To use Tutela, visit https://www.tutela.xyz.
As promising privacy-preserving machine learning technology, federated learning enables multiple clients to train the joint global model via sharing model parameters. However, inefficiency and vulnerability to poisoning attacks significantly reduce federated learning performance. To solve the aforementioned issues, we propose a dynamic asynchronous anti poisoning federated deep learning framework to pursue both efficiency and security. This paper proposes a lightweight dynamic asynchronous algorithm considering the averaging frequency control and parameter selection for federated learning to speed up model averaging and improve efficiency, which enables federated learning to adaptively remove the stragglers with low computing power, bad channel conditions, or anomalous parameters. In addition, a novel local reliability mutual evaluation mechanism is presented to enhance the security of poisoning attacks, which enables federated learning to detect the anomalous parameter of poisoning attacks and adjust the weight proportion of in model aggregation based on evaluation score. The experiment results on three datasets illustrate that our design can reduce the training time by 30% and is robust to the representative poisoning attacks significantly, confirming the applicability of our scheme.
Recently, many Delegated Proof-of-Stake (DPoS)-based blockchains have been widely used in decentralized applications, such as EOSIO, Tron, and Binance Smart Chain. Compared with traditional PoW-based blockchain systems, these systems achieve a higher transaction throughput and are well adapted to large-scale scenes in daily applications. Decentralization is a key element in blockchain networks. However, little is known about the evolution of decentralization in DPoS-based blockchain networks. In this paper, we conduct a systematic analysis on the decentralization of DPoS with data from up to 135,000,000 blocks in EOSIO, the first successful DPoS-based blockchain system. We characterize the decentralization evolution of the two phases in DPoS, namely block producer election and block production. Moreover, we study the voters with similar voting behaviors and propose methods to discover abnormal mutual voting behaviors in EOSIO. The analytical results show that our methods can effectively capture the decentralization evolution and abnormal voting phenomena in the system, which also have reference significance for other DPoS-based blockchains.
Ch Anwar Ul Hassan, Muhammad Hammad, Jawaid Iqbal, Saddam Hussain · 8 authors
Developing an electronic voting system that meets the practical needs of administrators has been a difficult task for a long time. Now, blockchain technologies solve this problem by providing a distributed ledger with immutable, encrypted, and secure transactions. Distributed ledger technologies are an interesting technological leap in the field of data innovation, transparency, and trustability. In public blockchain, distributed ledger technology is widely used. The blockchain technology can be used in an almost infinite number of ways to benefit from sharing economies. The purpose of this study is to assess how blockchain may be utilized to build electronic voting systems that can be used as a service. The purpose of electronic voting systems is explained in this article, as are the technological and legal limitations of employing blockchain as a service. Then, using blockchain as a foundation, we propose a new electronic voting system that fixes the flaws we observed. In general, this paper evaluates the capabilities of distributed ledger technologies by depicting a contextual investigation in order to fine-tune the process of political election decisions and employing a blockchain-based application that improves security and lowers the cost of conducting nationwide elections.
Compared with the classical structure with only one controller in software-defined networking (SDN), multi-controller topology structure in SDN provides a new type of cross-domain forwarding network architecture with multiple centralized controllers and distributed forwarding devices. However, when the network includes multiple domains, lack of trust among the controllers remains a challenge how to verify the correctness of cross-domain forwarding behaviors in different domains. In this paper, we propose a novel secure multi-controller rule enforcement verification (BlockREV) mechanism in SDN to guarantee the correctness of cross-domain forwarding. We first adopt blockchain technology to provide the immutability and privacy protection for forwarding behaviors. Furthermore, we present an address-based aggregate signature scheme with appropriate cryptographic primitives, which is provably secure in the random oracle model. Moreover, we design a verification algorithm based on hash values of forwarding paths to check the consistency of forwarding order. Finally, experimental results demonstrate that the proposed BlockREV mechanism is effective and suitable for multi-controller scenarios in SDN.
Conventional electronic voting systems use a centralized scheme. A central administration of these systems manages the entire voting process and has partial or total control over the database and the system itself. This creates some problems, accidental or intentional, such as possible manipulation of the database and double voting. Many of these problems have been solved thanks to permissionless blockchain technologies in new voting systems; however, the classic consensus method of such blockchains requires specific computing power during each voting operation. This has a significant impact on power consumption, compromises the efficiency and increases the system latency. However, using a permissioned blockchain improves efficiency and reduces system energy consumption, mainly due to the elimination of the typical consensus protocols used by public blockchains. The use of smart contracts provides a secure mechanism to guarantee the accuracy of the voting result and make the counting procedure public and protected against fraudulent actions, and contributes to preserving the anonymity of the votes. Its adoption in electronic voting systems can help mitigate part of these problems. Therefore, this paper proposes a system that ensures high reliability by applying enterprise blockchain technology to electronic voting, securing the secret ballot. In addition, a flexible network configuration is presented, discussing how the solution addresses some of the security and reliability issues commonly faced by electronic voting system solutions.
Bangyao Du, Debiao He, Min Luo, Cong Peng · 5 authors
Covert communication is designed for hiding the subliminal communication which takes place between both of the speakers and their relationship. The traditional covert communication utilizes the centralized channel and the third‐party central node or authority to distribute messages which leads to a lack of undetectability, antitraceability, and robustness. In recent years, there have been attempts to apply the blockchain to covert communication solutions, for the characteristics of blockchain such as decentralization, openness, and trustworthiness. In this paper, based on the analysis of the literature and the classification according to the hiding position, we identify four kinds of covert communication: Address Channel, Value Channel, DSA (Digital Signature Algorithm) Channel, and Script Channel, which will help inform future research agenda.
Open access
Internet Traffic Analysis and Secure E-voting
Advanced Steganography and Watermarking Techniques
This thesis presents a generalised comprehensive framework for evaluating anonymity of cryptocurrency schemes. The framework was developed using security modelling with emphasis on a wide range of factors affecting anonymity, irrespective of the underlying implementation. The case studies presented in the thesis demonstrate how this framework facilitates the evaluation of anonymity of different cryptocurrencies in a standardised manner and the analysis of these findings reveals the complexity of the notion of anonymity.