Yuye Han, Hong Chen, Zhijie Qiu, Lei Luo · 5 authors
As an essential means of privacy protection technology, zero-knowledge proof has gradually been applied into various fields with the development of blockchain technology, such as the Internet of Vehicles and Bitcoin. Personal comprehensive credit score as a measure to promote social governance is closely related to personal privacy. Although there are currently credit score calculation systems for various application scenarios, these systems almost ignore user privacy protection, which leads to user information leakage or abuse. The combination of zero-knowledge proof and personal credit score calculation has been studied by a number of researchers at the present stage. However, all data are provided by users directly in the current schemes, which did not consider the data authenticity under the situation that users provided false data. In this paper, we utilize zero-knowledge proof to design a novel privacy protection scheme for personal credit score calculation, taking into account the authenticity verification of multi-dimensional user data. In addition, our scheme also proposes the concept of a universal verification platform based on blockchain for personal credit scores. This platform has more substantial applicability and versatility for any qualified institution that requires querying and verifying userâs credit scores. At the end of the paper, we conducted a security analysis and performance evaluation for the overall scheme.
In privacy-preserving machine learning, it is less obvious to verify correct behavior of participants because they are not supposed to reveal their inputs in cleartext to other participants. It is hence important to make federated machine learning robust against data poisoning and related attacks. While input data can be related to a distributed ledger (blockchain), a less studied input is formed by the random sampling parties perform. In this paper, we describe strategies based on zero knowledge proofs to allow parties to prove they perform sampling (and other computations) correctly. We sketch a number of alternative ways to implement our idea and provide some preliminary experimental results.
The rapid development of the automotive Industrial Internet of Things requires secure networking infrastructure toward digitalization. Cybertwin (CT) is a next-generation networking architecture that serves as a communication, and digital asset owner, and can make the Vehicle-to-Everything (V2X) network flexible and secure. However, CT itself can publish end usersâ digital assets to other entities as a service, making data security and privacy major obstacles in the realization of V2X applications. Motivated from the aforementioned discussion, this article presents BDTwin, a blockchain and deep-learning-based integrated framework to enhance security and privacy in CT-driven V2X applications. Specifically, a blockchain scheme is designed to ensure secure communication among vehicles, roadside units, CT-edge server, and cloud server using a smart contract-based enhance-Proof-of-Work (ePoW) and Zero Knowledge Proof (ZKP)-based verification process. Smart contracts are used to enforce rules and regulations that govern the behavior of V2X entities in a nondeniable and automated manner. In a deep-learning scheme, an autoregressive-deep variational autoencoder model is combined with attention-based bidirectional long short-term memory (A-BLSTM) for automatic feature extraction and attack detection by analyzing CT-edge servers data in a V2X environment. Security analysis and experimental results using two different sources, ToN-IoT and CICIDS-2017 show the superiority of the proposed BDTwin framework over some baseline and recent state-of-the-art techniques.
Johan Colding, Stephan Barthel, Robert Ljung, Felix Eriksson · 5 authors
Climate change and the coupled loss of ecosystem services pose major collective action problems in that all individuals would benefit from better cooperation to address these problems but conflicting interests and/or incomplete knowledge discourage joint action. Adopting an inductive and multiâlayered approach, drawing upon the authorsâ previous research on urban commons, we here summarize key insights on environmentally oriented urban commons and elaborate on what role they have in instigating climateâproofing activities in urban areas. We deal with three types of urban commons, i.e., âurban green commons,â âcoworking spaces,â and âcommunity climate commons.â We describe how allotment gardens, community gardens, and other types of urban green commons contribute to environmental learning that may boost understanding of environmental issues and which constitute important learning arenas for climateâchange mitigation and adaptation. We also deal with the newly emerging phenomenon of coworking spaces that share many essential institutional attributes of urban commons and which can work for climateâchange mitigation through the benefits provided by a sharing economy and through reduction of domestic transportation and commuting distance. Community climate commons represent commons where local communities can mobilize together to create shared lowâcarbon assets and which hold the potential to empower certain segments and civil society groups so that they can have greater influence and ownership of the transformation of reaching netâzero carbon goals. We conclude this article by identifying some critical determinants for the upâscaling of environmentally oriented urban commons.
With the increasing complexity of the network environment, the traditional authentication technology has exposed its disadvantages such as low efficiency and power concentration. At the same time, the continuous development of information technology also puts forward higher requirements for authentication technology, for example, to realize authentication anonymization while ensuring authentication efficiency and dishonest users can be held accountable. In this paper, cross-domain authentication of heterogeneous networks is analyzed in detail, and a Blockchain-based Supervised Anonymous Cross-domain Authentication (BSA-CA) scheme is proposed. In this scheme, we retain the original infrastructure of the two trust domains. The trust network of users is established in the Blockchain system, and the trust model of heterogeneous cross-domain authentication is constructed by using zero-knowledge proof method. The BSA-CA scheme uses group signature to design anonymous supervisory properties. System analysis results show that the BSA-CA scheme has a good balance between security and authentication efficiency.
Radio frequency identification technology (RFID) is widely used due to its advantages of contactless identification. How to ensure the location privacy of tags and their users has become an urgent problem in the development of RFID technology. In order to resist active attacks such as tampering and counterfeiting caused by rewriting encryption and canceling encryption by malicious attackers. According to the existing location privacy protection schemes, this paper uses non-interactive zero-knowledge proof (NIZK) and universal re-encryption, then designs a publicly verifiable location privacy re-encryption scheme. In this scheme, all calculations are performed by the anonymizer. The anonymizer not only performs the ciphertext re-randomization operation, but also needs to provide a NIZK for this. The next anonymizer must verify the proof before re-randomization. The tag only needs to provide a certain reading and writing function to ensure that the ciphertext re-randomized each time will not be tampered with. We can see that this scheme can well protect the tag and user's location privacy through analysis.
In response to the rapid growth of credit-investigation data, data redundancy among credit-investigation agencies, privacy leakages of credit-investigation data subjects, and data security risks have been reported. This study proposes a privacy-protection scheme for a credit-investigation system based on blockchain technology, which realizes the secure sharing of credit-investigation data among multiple entities such as credit-investigation users, credit-investigation agencies, and cloud service providers. This scheme is based on blockchain technology to solve the problem of islanding of credit-investigation data and is based on zero-knowledge-proof technology, which works by submitting a proof to the smart contract to achieve anonymous identity authentication, ensuring that the identity privacy of credit-investigation users is not disclosed; this scheme is also based on searchable-symmetric-encryption technology to realize the retrieval of the ciphertext of the credit-investigation data. A security analysis showed that this scheme guarantees the confidentiality, the availability, the tamper-proofability, and the ciphertext searchability of credit-investigation data, as well as the fairness and anonymity of identity authentication in the credit-investigation data query. An efficiency analysis showed that, compared with similar identity-authentication schemes, the proof key of this scheme is smaller, and the verification time is shorter. Compared with similar ciphertext-retrieval schemes, the time for this scheme to generate indexes and trapdoors and return search results is significantly shorter.
Blockchain systems face two emergent problems, namely scalability and privacy, each of which has been addressed independently. However, how to achieve privacy and scalability simultaneously remains a challenging problem for blockchains. In this article, we propose a privacy-preserving and scalable permissioned blockchain system called HyperMaze employing the zero knowledge proof technique and a hierarchical system architecture. It gains scalability by adopting a hierarchy of multiple blockchains that processes transactions in parallel. We design anID-based dual-balance account modelwhere an identity-based account is associated with two types of balancesâa plaintext balance and a private (zero-knowledge) balance. Furthermore, we design a two-phase cross-chain transaction mechanism (2PXT) to achieve transaction privacy for both intra-chain and cross-chain transactions. We rigorously formulate a security model for HyperMaze under the universal composability framework, and then provide a simulation-based security proof. A prototype of HyperMaze is implemented and a series of experiments are conducted over up to 2,600 nodes to evaluate its performance. The experimental results show that a 4-level, (7,10)-threshold, 6-ary HyperMaze system can reach 19,440 TPS and the transaction confirmation latency is only 9.5 seconds. To our best knowledge, HyperMaze is the first high-throughput privacy-preserving blockchain whose throughput is over 19,000 TPS.
In the blockchain-based energy transaction scenario, the decentralization and transparency of the ledger will cause the usersâ transaction details to be disclosed to all participants. Attackers can use data mining algorithms to obtain and analyze usersâ private data, which will lead to the disclosure of transaction information. Simultaneously, it is also necessary for regulatory authorities to implement effective supervision of private data. Therefore, we propose a supervisable energy transaction data privacy protection scheme, which aims to trade off the supervision of energy transaction data by the supervisory authority and the privacy protection of transaction data. First, the concealment of the transaction amount is realized by Pedersen commitment and Bulletproof range proof. Next, the combination of ElGamal encryption and zero-knowledge proof technology ensures the authenticity of audit tickets, which allows regulators to achieve reliable supervision of the transaction privacy data without opening the commitment. Finally, the multibase decomposition method is used to improve the decryption efficiency of the supervisor. Experiments and security analysis show that the scheme can well satisfy transaction privacy and auditability.
Open access
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Suguru is a paper and pencil puzzle invented by Naoki Inaba. The goal of the game is to fill a grid with numbers between 1 and 5 while respecting three simple constraints. We first prove the NP-completeness of Suguru puzzle. For this we design gadgets to encode the PLANAR-CIRCUIT-SAT in a Suguru grid. We then design a physical Zero-Knowledge Proof (ZKP) protocol for Suguru. This ZKP protocol allows a prover to prove that he knows a solution of a Suguru grid to a verifier without leaking any information on the solution. To construct such a physical ZKP protocol, we only rely on a few physical cards and adapted encoding. For a Suguru grid with n cells, we only use 5n+5 cards. Moreover, we prove the three classical security properties of a ZKP: completeness, extractability, and zero-knowledge.
With the fast boom of Internet of Medical Things (IoMT) devices and an increasing focus on personal health, personal health data are extensively collected by IoMT and stored as personal health records (PHRs). PHRs are frequently shared for accurate diagnosis, prognosis prediction, health advice consulting, etc. Since PHRs are highly private, the data-sharing process leads to wide-ranging concerns on privacy leakage and security compromise. Existing research has shown that the centralized systems, as the mainstream mode, are under the great risks. Motivated by this, we propose a consortium blockchain-based PHR management and sharing scheme, which is both security aware and privacy preserving. We adopt the interplanetary file system (IPFS) to store the PHR ciphertext of IoMT. Then, zero-knowledge proof can provide evidence for verifying keyword index authentication on blockchain. Moreover, the scheme jointly leverages modified attribute-based cryptographic primitives and tailor-made smart contracts to achieve secure search, privacy preservation, and personalized access control in IoMT scenarios. Security analysis is conducted to show that the designed protocols attain the expected design goals. This is followed by extensive evaluation results derived from real-world data sets, which demonstrate the superiority of the proposed scheme over current leading ones.
In an electronic voting system, authentication is used to ensure that the voter is legitimate without knowing his/her identity, while the vote collectors verify the data is received from a legitimate user without knowing the identity of the voter. One of the authentication schemes that fulfilled this requirement is called a deniable authentication scheme, where the receiver can prove the source of the message while another party cannot identify the source of the message. In 2013, Li-Takagi et al. proposed a deniable authentication scheme. However, Li-Takagi's scheme has weaknesses if the receiver fully cooperates with the third party. In this case, the third party can identify the source of a given message. In the proposed method, zero-knowledge proof is introduced to preserve the anonymity of the deniable authentication scheme when the receiver fully cooperates with the third party. Based on the analysis, the proposed scheme fulfills the requirement of the deniable authentication scheme when the receiver fully cooperates with the third party. However, the proposed scheme has additional computation costs for securing the shared secret key. Two attack schemes that are carried out on both Li-Takagi and the proposed scheme are the MITM attack and the impersonation attack. The probability of breaking the proposed scheme using an MITM attack is lower than when using Li-Takagi's scheme, but the probability of breaking the proposed scheme using an impersonation attack is the same as Li-Takagi's scheme.
Rabimba Karanjai, Lei Xu, Zhimin Gao, Lin Chen · 6 authors
In this paper, we present the design and implementation of a privacy preserving event based UTXO (Unspent Transaction Output) transaction system. Unlike the existing approaches that often depend on smart contracts where digital assets are first locked in a vault, and then released according to event triggers, the event based transaction system encodes event outcome as part of the UTXO note and safeguards event privacy by shielding it with zero-knowledge proof based protocols such that associations between UTXO notes and events are hidden from the validators. Without relying on any triggering mechanism, the proposed transaction system separates event processing from the transaction processing where confidential event based UTXO notes (event based UTXOs or conditional UTXOs) can be transferred freely with full privacy in an asynchronous manner, only with their asset values conditional to the linked event outcomes. The main advantage of such design is that it enables free trade of event based digital assets and prevents the assets from being locked. We implemented the proposed transaction system by extending the Zerocoin data model and protocols. The system is implemented and evaluated using xJsnark.
Zero-knowledge proofs (ZKPs) have garnered much attention recently. They have witnessed applicability in anonymizing tokens (e.g., Tornado Cash) and increasing transaction throughput (e.g., ZK-Rollups) for blockchains backing cryptocurrencies. ZKPs are touted to offer great potential for future blockchain applications that operate in a priori trustless environments across administrative boundaries. This short note discusses the integration of the ZK-STARK-based proof system into the OpenLibra blockchain. We generically describe the interaction of the involved ZKP capabilities with OpenLibra and showcase an open-sourced proof-of-concept implementation.
The Dutch news cycle was mainly dominated by two topics this year: the ongoing COVID-19 pandemic and the formation of a new coalition government. The formation process followed the general elections of March and was accompanied by various scandals and leaked formation notes. After a record nine months, in January 2022, at last a coalition agreement was formedâbetween the exact four parties that had also formed the preceding coalition. In the meantime, many existing environmental challenges lingered on or were exacerbated, without much political action being taken to address them. There were some notable changes to the political discourse on some of these problems, however. The need to address climate change, for instance, was put high on the agenda of the formation talks after the intense rainfall and high water of July 2021 in the south of the Netherlands and neighbouring areas in Belgium and Germany. In a press conference in early August, prime minister Mark Rutte (at the time, demissionary, now prime minister again) stated that âthe Netherlands became seventh during the Olympic games. In the Olympic Games of the Climate, we can be number one tooâ (translated by author). It remains to be seen, of course, whether this ambitious spirit will be met with corresponding actions. Considering various political and socio-economic developments in 2021, there are reasons to be both optimistic as well as pessimistic, as will be discussed below. Home of the famous Urgenda ruling, the Netherlands will be known to many as a catalyst for climate litigation across the globe. At the national level, Urgenda has also paved the way for new legal challenges to follow suit. This year, the Dutch branch of the environmental non-governmental organization (NGO) Friends of the Earth (Milieudefensie) successfully sued Shell Plc for failing to reduce their emissions. The origins of the case lay in early April 2018, when Milieudefensie sent a notice letter to the chief executive officer of Shell to explain why it is of the position that the company, through its corporate activities and strategy, is breaching its duty of care by causing climate damage across the globe and undermining the ambitions of the Paris Agreement. A month later, Shell responded that it did not find Milieudefensieâs claims and demands justified. A lawsuit was then initiated by Milieudefensie, in which the environmental NGO was joined by six additional environmental NGOs and more than 17,000 co-plaintiffs from civil society. The case was heard by the District Court in The Hague in December 2020, with the ruling delivered on 26 May 2021 (ECLI:NL:RBDHA:2021, 5339). In its historic judgment, the District Court found that that Shell must reduce its global net carbon emissions by 45 percent by 2030 as compared to 2019 levels. In detailing its ruling, the court started from the basis that continued emissions will lead to dangerous and irreversible climate change, referring to the reports of the International Panel on Climate Change as well as national climate reports. The court subsequently found that Milieudefensie could bring a collective action pursuant to Book 3, section 305a of the Dutch Civil Code, which reads that a foundation or association with full legal capacity may institute legal proceedings for the protection of similar interests of other persons. Important to add here is that, although the court recognized that the âentire world population is served by curbing dangerous climate changeâ (para. 4.2.3), the diffuse manner and time in which climate risks manifest globally mean that the interests of current and future generations of the worldâs population cannot be bundled. The interests of current and future Dutch generations were considered sufficiently similar for a collective action to be taken by these environmental NGOs, however, meaning that Milieudefensie could take the case on behalf of Dutch residents. Milieudefensie had further requested Dutch law to be applicable on the actions of Shell on the basis of Article 7 of EC Regulation 864/2007 on the Law Applicable to Non-contractual Obligations. The court accepted this on the basis that the corporate policy of the Shell group âconstitutes an independent cause of the damage, which may contribute to environmental damage and imminent environmental damage with respect to Dutch residents and the inhabitants of the Wadden regionâ (para. 4.3.6.). In detailing its judgment, the court ruled that âthe CO2 emissions for which [Shell] can be held responsible by their nature pose a very serious threat, with a high risk of damage to Dutch residents and the inhabitants of the Wadden region and with serious human rights impactsâ (para. 4.4.54). Based on an unwritten standard of care pursuant to Book 6, section 162 of the Dutch Civil Code, the court ordered Shell to meet a reduction obligation of 45 percent by 2030, provisionally effective, meaning Shell must comply even though an appeal is still open. The case is groundbreaking in that it is the first time that a court of law found a private company to have a legal duty to reduce emissions. On top of that, the court ordered a concrete emission reduction target binding upon the company. Environmental groups across the world are now reflecting on what can be learned from this case, and how the case can be replicated in other jurisdictions and sectors. The Dutch court has helpfully published an English translation of this case that may be of assistance to such groups. It is important to emphasize here that the final word on this case has not been said. In fact, Shell has already confirmed it will appeal the judgment, with the companyâs chief executive officer noting that, although they agree that âurgent action is needed and we will accelerate our transition to net zero,â the company will appeal the ruling because âa court judgment, against a single company, is not effectiveâ (see 2021 media releases <http://www.shell.com>). Instead, the company advocates in its press release for clear, ambitious policies that can promote change across the entire energy system, and at a global level. Whether Shell thus far has played a constructive part in driving such changes to government policies can be debated, of course. Interestingly, this was not Milieudefensieâs only win against Shell in 2021. In fact, on 29 January, the Court of Appeal of The Hague ruled that Shellâs Nigerian subsidiary is liable for the consequences of two oil spills in Nigeria (ECLI:NLGDHA:2021, 132, 133, and 134). This case, brought by four Nigerian farmers and Milieudefensie, had been continuing for thirteen years and relates to oil leaks that took place between 2004â7. Shell disclaimed liability, stating that the oil spills had been caused by sabotage, as a result of which there would be no liability under Nigerian law. The Court of Appeal did not follow this reasoning. That a Dutch court could have jurisdiction and competence to judge compliance with Nigerian law had been decided in an earlier ruling in 2015, due to the fact that the parent company of the Nigerian subsidiary was based in the Netherlands (ECLI:NL:GHDHA:2015, 3586, 3587 and 3588). A final note regarding climate litigation relates to the impact of climate litigation in practice. In 2015, the District Court of The Hague ruled that the Dutch State would have to ensure that carbon dioxide emissions are reduced by 25 percent in 2020 as compared to 1990. Even though the government decided to (unsuccessfully) appeal this judgment all the way up to the Supreme Court level, the fact remains that the emission reduction requirement was binding from the start. In 2021, there were no signs that the state had lived up to the Courtâs judgment. As a consequence, Urgenda decided to initiate new proceedings to request the judge to impose a penalty payment on the state to secure compliance with the judgment. In early 2022, final emissions data were published by the Dutch Environmental Assessment Agency, which showed that in 2020, 25.5 percent less carbon dioxide had been emitted, compared to 1990. The most recent data shows that in 2021, however, emissions had gone up again, towards a 23.9 percent reduction compared to 1990. It is important to note here that the original reduction requirement relates to the absolute minimum needed from industrialized countries to remain below a temperature rise of two degrees Celsius (not 1.5 degrees Celsius). As it turns out, not even a court judgment has thus far incentivized the Dutch government to indeed meet this minimum reduction. Besides being problematic from a climate action perspective, such non-action also threatens the functioning of the rule of lawârechtsstaat, in the Dutch contextâin which governments are bound by the law and must respect the judgments of independent judges. In both respects, it seems crucial to remain vigilant of the countryâs commitment to climate action in the years to come, ensuring that the Urgenda judgment is in fact respected. In the previous report on the Netherlands in this Yearbook, Lorenzo Squintani explained in detail how the country entered a societal and political gridlock when the Dutch Council of State, in its judgment of 2019, found the Dutch Programmatic Approach to nitrogen oxides to be incompatible with EU nature conservation law. Squintani described in his report how the âsearch for a solution to the low quality of soil in Natura 2000 sites is greatly overshadowed by the search for a solution for economic interestsâ (at 382). This observation, in many ways, holds true today, and an unmistakable amount of scientific evidence shows that excessive nitrogen emissions remain a core threat to biodiversity and nature values in the country. Over the course of the past year, measures were initiated that may hopefully help change this course, however. First, on 1 July, the Act on nitrogen reduction and nature improvement (stikstofreductie en natuurverbetering) entered into force, amending existing nature legislation. The Act sets a time-based result obligation for ensuring that protected nature sites have a healthy nitrogen dispositionânamely, 40 percent of the coverage of such sites in 2025, 50 percent in 2030, and 74 percent in 2035. In addition, the Act requires the establishment of a governmental program with concrete measures and intermediary goals to realize these binding targets, accompanied by monitoring requirements. In the coalition agreement, presented on 15 December, a total amount of âŹ25 billion was made available to address the nitrogen crisis in the period until 2035, of which âŹ20 billion must have been spent by the year 2030. For spending these funds, the national government puts the responsibility at the provincial level. The aim here is to develop more of a locality-based approach, with the twelve provinces being required to develop detailed plans on how nitrogen emissions will be addressed per individual area within their province. The provinces must present their plans in 2023âwhich may then allow for further collaboration and coordination between themâafter which, the national government will evaluate these plans and provide the funding. Although the chosen approach may provide provinces with the necessary flexibility to adapt measures to their local circumstances, the success of this approach is very much dependent on the commitment of individual provincesâwhich has proven to be fiddly in the past. Besides the stipulated budget, the exact manner in which the nitrogen crisis will be addressed is thus still very much unclear. In the agricultural domainâthe main source of nitrogen emissions in the countryâthe focus still seems to be on financial instruments to incentivize a shift towards circular agriculture with drastically reduced nitrogen outputs. Farms with high emissions that cannot reduce their emissions and are located close to protected nature sites may be offered a government buyout orâalthough this is not confirmedâmay be forced to sell their farm. Such forced buyouts, however, are time-consuming and expensive, on top of being highly politically sensitive, particularly in light of the large-scale farmer protests of 2019â20. As such, this does not seem to be the preferred government option. Besides measures flowing from the Nitrogen Act, the Dutch draft National Strategic Plan for the Common Agricultural Policy 2023â7 is another instrument that may play an important role in addressing nitrogen emissions. Although the word ânitrogenâ occurs no less than sixty-three times on the in the total 107 pages of this plan, the actual measures that may be used are not made very concrete. Various generic types of interventions are mentioned that may contribute to reducing nitrogen emissions, including the use of eco-schemes, agri-environmental subsidies, enhancing cooperation, and promoting knowledge and information distributing (at 30). In addition, the plan seeks to commit funds towards the strengthening of cooperation between farmers and other area partners, so that problems can addressed at a landscape scale. This includes subsidies for the development of area plans that stipulate concrete measures per area, including the extensification of high emission farms located close to nitrogen-sensitive Natura 2000 sites. Overall, it remains to be seen to what extent instruments of the policy will be employed to help meet the objectives of the new Nitrogen Act. Despite these new measures, over the course of the year, several new cases were brought (and won) by environmental NGOs to enforce rules on nitrogen, highlighting continued faults in the governmentâs nitrogen approach and particularly the calculation methods of nitrogen permits (see, for example, ECLI:NL:RBOBR:2021, 6389). The only real way to change this course seems to be to for the (provincial) government to stop searching for paper solutions and start addressing the various existing environmental challenges in a holistic, non-isolated manner. This also appears as a central plank in the coalition agreement, in which it is stipulated that nitrogen measures should also help, for instance, to address biodiversity declines and improve water quality. It is not a stretch to say that the Netherlands can rightly anticipate new (legal) challenges about that second aspect, as it is increasingly becoming clear that the Netherlands are nowhere near on track to meet the binding targets of EC Directive 2000/60 Establishing a Framework for Community Action in the Field of Water Policy. A more holistic approach to law and policy making, in which environmental and other societal challenges are no longer dealt with in isolation, will be of key importance here. This year also presented several interesting rulings by the Dutch Council of State on the application of environmental democracy rights flowing from the Convention on Access to Information, Public Participation in Decision-making and Access to Justice in Environmental Matters (Aarhus Convention). The point of departure for us here is a ruling by the Court of Justice of the European Union (CJEU) on Stichting Varkens in Nood and Others, of 14 January 2021 (C-826/18). In brief, this case dealt with a request for a preliminary reference submitted by the Dutch District Court of Limburg, seeking clarification on Articles 6 and 9(2) of the Aarhus Convention. These provisions respectively provide that a decision to authorize environmental activities must be subject to a public participation procedure, and that there should be a right of access to justice to subsequently challenge such decisions. In the Netherlands, any person can participate in a decision-making procedure by making a submission on a draft decision. There is no obligation for public actors to adapt draft decisions based on submissions received. In Article 6:13 of the Dutch General Administrative Law Act, then, it is stipulated that only interested parties that have submitted observations on a draft decision during the preparatory procedure may subsequently challenge the adopted decision in court. Exceptions to this rule are possible when an applicant is able show that this requirement could not reasonably be metâfor instance, because a draft decision was not publicized. In general, however, the rule stands that, without having participated in the decision-making process by making a (written or oral) submission, there is no subsequent access to justice. In the preliminary ruling, the CJEU found that this requirement is not in line with the Aarhus Convention. Instead, interested parties should have the right to appeal a decision, even if they have not made submissions in the preparatory phase. In addition, the court ruled that people who are deemed interested parties for the purpose of making submissions should also, subsequently, be allowed to appeal a decision before a court of law. If the Netherlands thus allows any person to make submissions, it should also allow any person to subsequently challenge an adopted decision in court. On 15 April, the Dutch Council of State subsequently ruled that, indeed, interested parties can also appeal decisions if they have not made submissions. For environmental NGOs and other potential applicants, this may be quite the relief. As recent empirical work on the application of the Aarhus Convention shows, the submission requirement can be relatively burdensome in practice, especially for smaller environmental groups. On paper, this submission requirement serves to improve the decision-making process by ensuring that different considerations and perspectives could be considered before a final decision comes to being. In practice, it seems that submissions hardly led to decisions being adapted in the preparatory phase. As such, the main reason for making submissions was purely to be able to challenge a decision, if need be, later. After these judgments, it is now the legislatorâs turn to decide how to incorporate these rulings into domestic law, ensuring compliance with the Aarhus Convention. With a focus on the domains of climate, nature, and environmental democracy, this report has reasons to be optimistic as well as regarding the development of environmental law in the there are several to a close on for the future of environmental law in the country. In to climate in both Shell cases that were the country of of the parent company played an important role in the It can be that can climate litigation proceedings if they are based in countries with less climate or less Whether due to with Dutch climate cases or other at the of 2021, Shell decided to its to A environmental NGO has already that it will bring an action against the of Shell for failing to develop company in line with the Paris in breaching their under the law. In the it should clear whether climate litigation will branch also in this new or In to nitrogen, then, when the new coalition government was presented on January 2022, the a new that the is in the the minister of nature and The of this new minister is to nature and in a by As the new Act on nitrogen reduction and nature improvement is being and the of to addressing excessive nitrogen emissions are put to it can only be that the environmental challenges at play will be as environmental democracy, it is now thus the legislatorâs turn to ensure that Dutch law is in line with the new line of case law discussed it is also in the that, to up to the ambitions of the Aarhus not only changes also changes in the way that public actors environmental democracy in are As has also been in previous year much work remains to be in this
Most of the blockchain-based identity authentication systems are based on public blockchain, which are still essentially traditional centralized identity management and verification methods, making it difficult to meet the needs of trusted access and fine-grained access control in microgrids. Therefore, based on the FISCO BCOS consortium blockchain technology, a distributed identity authentication system supporting multi-center was designed. A DID-based identity management protocol to achieve autonomous control of user identity in a practical scenarios was designed. Distributed trusted access technology for end nodes in microgrids was studied, and privacy-protecting credentials based on zero-knowledge proof were designed. This scheme meets the requirements of trustworthy and verifiable user identity in different privacy security scenarios, and achieves autonomous control of entity identity, fine-grained access control and trusted data exchange. The usability and effectiveness of the proposed algorithm are demonstrated through system experiments and performance analysis.
Internet of Vehicles (IoV) has become an indispensable technology to bridge vehicles, persons and infrastructures, and is promising to make our cities smarter and more connected. It enables vehicles to exchange vehicular data (e.g., GPS, sensors, and brakes) with different entities nearby. However, sharing these vehicular data over the air raises concerns about identity privacy leakage. Besides, the centralized architecture adopted in existing IoV systems is fragile to single point of failure and malicious attacks. With the emergence of blockchain technology, it has the chance to solve these problems due to its features of tamper-proof, traceability and decentralization. In this paper, we propose a privacy-preserving vehicular data sharing framework based on blockchain. In particular, we design an anonymous and auditable data sharing scheme using Zero-Knowledge Proof (ZKP) technol-ogy so as to protect the identity privacy of vehicles while preserving the vehicular data auditability for Trusted Authorities (TAs). In response to high mobility of vehicles, we design an efficient multi-sharding protocol to decrease blockchain communication costs without compromising the blockchain security. We implement a prototype of our framework and conduct extensive experiments and simulations on it. Evaluation and analysis results indicate that our framework can not only strengthen system security and data privacy, but also increase the data authenticity verification efficiency by 5x comparing to existing privacy-preserving schemes.
Currently, the Internet of Things (IoT) is widely used by the emerging of internet-integrated wireless devices in daily life. In order to communicate and exchange data with each other, IoT devices must pass by a gateway that belongs to the same network. But, considering the mobility of such devices and their constraints, it becomes difficult to trust and to connect from a gateway to another. Therefore, this paper introduces a blockchain-based secure handover protocol. It ensures an anonymous mutual authentication solution between a mobile IoT device and a visited gateway by using Zero-Knowledge Proof (ZKP) protocol. To do, simulations have been performed thanks to a discrete events simulator. In addition to a good security level, compared with the most used protocol (DTLS), our simulation results lead to better performance in terms of temporal complexity, energy consumption, and communication cost.
Cryptography is traditionally considered as a main information security mechanism, providing several security services such as confidentiality, as well as data and entity authentication. This aspect is clearly relevant to the fundamental human right of privacy, in terms of securing data from eavesdropping and tampering, as well as from masquerading their origin. However, cryptography may also support several other (legal) requirements related to privacy. For example, in order to fulfil the data minimisation principleâi.e., to ensure that the personal data that are being processed are adequate and limited only to what is necessary in relation to the purposes for which they are processedâthe use of advanced cryptographic techniques such as secure computations, zero-knowledge proofs or homomorphic encryption may be prerequisite. In practice though, it seems that the organisations performing personal data processing are not fully aware of such solutions, thus adopting techniques that pose risks for the rights of individuals. This paper aims to provide a generic overview of the possible cryptographic applications that suffice to address privacy challenges. In the process, we shall also state our view on the public âdebateâ on finding ways so as to allow law enforcement agencies to bypass the encryption of communication.
Abstract We use a simplified version of the framework of resource monoids , introduced by Dal Lago and Hofmann, to interpret simply typed λ-calculus with constants zero and successor. We then use this model to prove a simple quantitative result about bounding the size of the normal form of λ-terms. While the bound itself is already known, this is to our knowledge the first semantic proof of this fact. Our use of resource monoids differs from the other instances found in the literature, in that it measures the size of λ-terms rather than time complexity.
Samiksha Kodgire Samiksha, Padma Adane, Ajay Jadhav, Aman R. Agrawal · 5 authors
Transactions over the internet have increased rapidly and so is the need to prove oneâs identity and have a secured system to keep records. To overcome identity theft and fraud cases, Self-Sovereign Identity (SSI) was introduced which gives the user complete control over their identity on the internet. Self-Sovereign Identity eliminates the centralized authority and brings Zero-knowledge proof concepts into account to help in easy transactions over the internet. It avoids revealing unnecessary information and correlation attacks. Self-Sovereign Identity, on top of blockchain public ledger features, provides an extra security layer to the system that can be used to monitor the entries in confidential places. This research paper describes a software module, that we have developed, to grant verifiable credentials to users. These credentials, on verification, can grant entry into any security system with which the module is integrated. The module utilizes the facilities provided by Hyperledger Indy and Hyperledger Aries for the creation of verifiable credentials and subsequent verification in a secure manner.
Quantum entangled states have shown distinguished features beyond any classical state. Many methods like quantum state tomography have been presented to verify entanglement. In this work, we aim to identify unknown entanglements with partial information of the state space by developing a nonlinear entanglement witness. The witness consists of a generalized Greenberger-Horne-Zeilinger-like paradox expressed by Pauli observables, and a nonlinear inequality expressed by density matrix elements. First, we verify unknown bipartite entanglements and study the robustness of entanglement witnesses against the white noise. Second, we generalize such a verification to unknown multipartite entangled states, including the Greenberger-Horne-Zeilinger-type states and the cluster states under local channel operations. Third, we give a quantum-information application related to the quantum zero-knowledge proof. Our results provide a useful method in verifying universal quantum computation resources with robustness against white noises. Our work is applicable to detect unknown entanglement without the state tomography.