Probabilistically Checkable Proofs (PCPs) allows a randomized verifier, with oracle access to a purported proof, to probabilistically verify an input statement of the form “x∈L” by querying only a few proof bits. Zero-Knowledge PCPs (ZK-PCPs) enhance standard PCPs to additionally guarantee that the view of any (possibly malicious) verifier querying a bounded number of proof bits can be efficiently simulated up to a small statistical distance. The first ZK-PCP construction of Kilian, Petrank and Tardos (STOC 1997), and following constructions employing similar techniques, necessitate that the honest verifier makes several rounds of queries to the proof. This undesirable property, which is inherent to their technique, translates into increased round complexity in cryptographic applications of ZK-PCPs. We survey two recent ZK-PCP constructions—due to Ishai, Yang and Weiss (TCC 2016-A), and Hazay, Venkitasubramaniam and Weiss (ITC 2021)—in which the honest verifier makes a single round of queries to the proof. Both constructions use entirely different techniques compared to previous ZK-PCP constructions, by showing connections to the seemingly-unrelated notion of leakage resilience. These constructions are incomparable to previous ZK-PCP constructions: while on the one hand the honest verifier only makes a single round of queries to the proof, these ZK-PCPs either obtain a smaller (polynomial) ratio between the query complexity of the honest and malicious verifiers or obtain a weaker ZK guarantee in which the ZK simulator is not necessarily efficient.
Traceability and trustiness are two critical issues in the logistics sector. Blockchain provides a potential way for logistics tracking systems due to its traits of tamper resistance. However, it is non-trivial to apply blockchain on logistics because of firstly, the binding relationship between virtue data and physical location cannot be guaranteed so that frauds may exist. Secondly, it is neither practical to upload complete data on the blockchain due to the limited storage resources nor convincing to trust the digest of the data. This paper proposes a traceable and trustable consortium blockchain for logistics T2L to provide an efficient solution to the mentioned problems. Specifically, the authenticated geocoding data from telecom operators’ base stations are adopted to ensure the location credibility of the data before being uploaded to the blockchain for the purpose of reliable traceability of the logistics. Moreover, we propose a scheme based on Zero Knowledge Proof of Retrievability (ZK BLS-PoR) to ensure the trustiness of the data digest and the proofs to the blockchain. Any user in the system can check the data completeness by verifying the proofs instead of downloading and examining the whole data based on the proposed ZK BLS- PoR scheme, which can provide solid theoretical verification. In all, the proposed T2L framework is a traceable and trustable logistics system with a high level of security.
We propose a new, unifying framework that yields an array of cryptographic primitives with certified deletion. These primitives enable a party in possession of a quantum ciphertext to generate a classical certificate that the encrypted plaintext has been information-theoretically deleted, and cannot be recovered even given unbounded computational resources. - For X \in {public-key, attribute-based, fully-homomorphic, witness, timed-release}, our compiler converts any (post-quantum) X encryption to X encryption with certified deletion. In addition, we compile statistically-binding commitments to statistically-binding commitments with certified everlasting hiding. As a corollary, we also obtain statistically-sound zero-knowledge proofs for QMA with certified everlasting zero-knowledge assuming statistically-binding commitments. - We also obtain a strong form of everlasting security for two-party and multi-party computation in the dishonest majority setting. While simultaneously achieving everlasting security against all parties in this setting is known to be impossible, we introduce everlasting security transfer (EST). This enables any one party (or a subset of parties) to dynamically and certifiably information-theoretically delete other participants' data after protocol execution. We construct general-purpose secure computation with EST assuming statistically-binding commitments, which can be based on one-way functions or pseudorandom quantum states. We obtain our results by developing a novel proof technique to argue that a bit b has been information-theoretically deleted from an adversary's view once they output a valid deletion certificate, despite having been previously information-theoretically determined by the ciphertext they held in their view. This technique may be of independent interest.
With the fast development of the industrial Internet, its interconnectivity poses new challenges for the cooperation of industrial entities. Cooperation among these entities is built on trust, and trust is based on high-quality industrial products at reasonable prices. A traceability system can play an essential role in objectively reflecting the production process and promoting this trust. However, traditional traceability systems often have data privacy issues. Because traceability data are collected or generated during the production process (namely, production-related data), they could be considered privacy data. Several researchers have introduced privacy protection schemes into the traceability system, such as authentication or encryption. Nevertheless, when a privacy protection scheme is established, the original data are disclosed to the legal user of the system, but the data may still be leaked intentionally or unintentionally. Except for data privacy issues, a traditional traceability system can be vulnerable to network attacks, data unavailability, and reliability issues. The authors conducted a study to overcome these shortcomings, and this paper reports the results. We built a traceability prototype system using a blockchain protocol and a zero-knowledge proof method. First, we built a blockchain to record key production process data, aiming to maintain data reliability and availability. Second, through an analysis of traceability purpose using production knowledge, the traceability purpose could be divided into multiple provable statements. By introducing privacy protection through a zero-knowledge proof, the traceability process was converted to proving relative statements. Finally, the statements were validated by a smart contract that provided openness and reliability during the traceability process. Analysis has shown that our approach could meet the requirements for high security and privacy. In addition, the paper also discusses the calculation cost of the traceability process to show our work’s viability. The traceability system described in this paper creates new possibilities for constructing a healthy and reliable trust relationship between production entities to provide further support in the development of the industrial Internet.
Music creation and its promotion are encouraged both in music education and through activities organized in the context of artistic creation as part of the education in question. Although copyright registration is the primary way authors protect their rights, this is not feasible in most cases, as the processes take a long time to complete and incur high costs. We utilize modern innovative technologies and their developments in copyright protection matters to increase security and trust in music education. In particular, an advanced model of ensuring the methods and innovation produced in music education processes is proposed, using blockchain technology and smart contracts. But given that, even in an advanced system like the proposed one, authentication evidence can be easily intercepted, this work proposes a single and robust identification scheme based on an innovative zero-knowledge proof (ZNP) system, which allows one side of communication to convince the other of its validity.
Open access
Blockchain Technology Applications and Security
Physical Unclonable Functions (PUFs) and Hardware Security
Privacy-preserving federated learning allows multiple users to jointly train a model with coordination of a central server. The server only learns the final aggregation result, thereby preventing leakage of the users’ (private) training data from the individual model updates. However, keeping the individual updates private allows malicious users to degrade the model accuracy without being detected, also known as Byzantine attacks. Best existing defenses against Byzantine workers rely on robust rank-based statistics, e.g., setting robust bounds via the median of updates, to find malicious updates. However, implementing privacy-preserving rank-based statistics, especially median-based, is nontrivial and unscalable in the secure domain, as it requires sorting of all individual updates. We establish the first private robustness check that uses high break point rank-based statistics on aggregated model updates. By exploiting randomized clustering, we significantly improve the scalability of our defense without compromising privacy. We leverage the derived statistical bounds in zero-knowledge proofs to detect and remove malicious updates without revealing the private user updates. Our novel framework, zPROBE, enables Byzantine resilient and secure federated learning. We show the effectiveness of zPROBE on several computer vision benchmarks. Empirical evaluations demonstrate that zPROBE provides a low overhead solution to defend against state-of-the-art Byzantine attacks while preserving privacy.
Jonathan Heiss, Elias Grünewald, Stefan Tai, Nikolas Haimerl · 5 authors
Federated learning may be subject to both global aggregation attacks and distributed poisoning attacks. Blockchain technology along with incentive and penalty mechanisms have been suggested to counter these. In this paper, we explore verifiable off-chain computations using zero-knowledge proofs as an alternative to incentive and penalty mechanisms in blockchain-based federated learning. In our solution, learning nodes, in addition to their computational duties, act as off-chain provers submitting proofs to attest computational correctness of param-eters that can be verified on the blockchain. We demonstrate and evaluate our solution through a health monitoring use case and proof-of-concept implementation leveraging the ZoKrates language and tools for smart contract-based on-chain model management. Our research introduces verifiability of correctness of learning processes, thus advancing blockchain-based federated learning.
Les preuves vérifiables de manière probabiliste (PCP, de l'anglais "probabilistically checkable proofs), les preuves interactives (IP, pour "interactive proofs") ou encore les preuves à divulgation nulle de connaissance ("zero-knowledge proofs") ont la particularité d'admettre une vérification probabilististe. Ces systèmes de preuves probabilistes interviennent dans les constructions de schémas de calcul vérifiable, des protocoles cryptographiques permettant de vérifier très rapidement qu'un long calcul a été correctement effectué. En 2016, un nouveau modèle de preuve a été introduit par Ben-Sasson, Chiesa et Spooner : celui des preuves interactives par oracle (IOP, pour "interactive oracle proofs"). Ce modèle généralise à la fois les PCPs et les IPs et a suscité beaucoup d'intérêt depuis son introduction. Le modèle IOP a mené à d'intéressants résultats théoriques sur les arguments non-interactifs succincts et transparents ainsi qu'à des déploiements industriels.Un problème récurrent dans les constructions de systèmes de preuves probabilistes est celui de tester efficacement la proximité à un code correcteur d'erreurs. Le but est de déterminer si un certain mot appartient à un code linéaire donné, ou bien s'il est éloigné de tout mot de ce code. Les tests de proximité à des codes polynomiaux peuvent être interprétés comme des tests de bas degré. Par exemple, un important sous-protocole utilisé dans de nombreuses constructions pratiques est un "IOP of Proximity" pour les codes de Reed-Solomon (Ben-Sasson et al., ICALP 2018).Dans cette thèse, nous proposons dans le modèle IOP des protocoles permettant de vérifier la proximité à des codes correcteur d'erreurs.En nous inspirant du test de proximité pour les codes de Reed-Solomon de Ben-Sasson et al., nous commençons par formuler un cadre abstrait et générique pour construire des "IOPs of Proximity" pour des codes linéaires et en analysons formellement les propriétés. Nous appliquons ensuite cette méthodologie à différentes familles de codes généralisant les codes de Reed-Solomon. Il s'agit d'une part de codes définis à partir d'évaluations de polynômes multivariés et, d'autre part, de codes de géométrie algrébrique définis sur des courbes. Nos protocoles permettent de tester la proximité à des codes présentant des propriétés attrayantes par rapport aux codes de Reed-Solomon (telles que des alphabets de petite taille), tout en ayant une efficacité similaire à la construction de Ben-Sasson et al.
Purpose BIM research to date has in general zeroed in on featuring the significance of BIM-enabled integration and collaboration (BIMIC) rather than giving exact proof of its occurrence. Accordingly, this research quantitatively explored the determinants of BIMIC in South Africa. Design/methodology/approach This research conceptualized a four-pillar model of BIM-enabled integration and collaboration. The speculations in the model were examined using SEM-MLE. Findings The aftereffects of the SEM-MLE demonstrated that network communication, knowledge sharing, and transfer, information sharing and exchange and trust-based relationships are critical determinants of BIMIC. The model's prescient power demonstrates an acceptable validity, and the boundary gauges showed that all the hypotheses were measurably huge. Research limitations/implications This research gives a hypothetical premise for further investigation of BIMIC by supporting the postulations on the occurrence of collaboration and integrations among the BIM-SCM. Practical implications The idea investigated involving SEM in this research gives a holistic view to the BIM managers in arranging BIM-based activities and overseeing BIM cycles and supply chain members. It likewise offers rules and structures for accomplishing and overseeing integration and collaboration among the BIM supply chain members. Originality/value Despite 20 years of exploration on the BIM concept and adoption, no idea has been given to clarify the determinants of integration and collaboration as a BIM cycle. The four-pillar model of BIMIC created and tested in this research clarified BIMIC and contributed a new model to the current literature on the BIM process.
Gonzalo Munilla Garrido, Johannes Sedlmeir, Matthias Babel
Analyses that fulfill differential privacy provide plausible deniability to individuals while allowing analysts to extract insights from data. However, beyond an often acceptable accuracy tradeoff, these statistical disclosure techniques generally inhibit the verifiability of the provided information, as one cannot check the correctness of the participants' truthful information, the differentially private mechanism, or the unbiased random number generation. While related work has already discussed this opportunity, an efficient implementation with a precise bound on errors and corresponding proofs of the differential privacy property is so far missing. In this paper, we follow an approach based on zero-knowledge proofs~(ZKPs), in specific succinct non-interactive arguments of knowledge, as a verifiable computation technique to prove the correctness of a differentially private query output. In particular, we ensure the guarantees of differential privacy hold despite the limitations of ZKPs that operate on finite fields and have limited branching capabilities. We demonstrate that our approach has practical performance and discuss how practitioners could employ our primitives to verifiably query individuals' age from their digitally signed ID card in a differentially private manner.
Giao Ky Duong, Nejla Nouaili, Hatem Zaag, Université Sorbonne Paris Nord, LAGA, CNRS(UMR7539), F-93430, Villetaneuse, France
In this paper, we revisit the proof of the existence of a solution to the semilinear heat equation in one space dimension with a flat blow-up profile, already proved by Bricmont and Kupainen together with Herrero and Velázquez. Though our approach relies on the well-celebrated method, based on the reduction of the problem to a finite-dimensional one, then the use of a topological 'shooting method' to solve the latter, the novelty of our approach lays in the use of a modulation technique to control the projection of the zero eigenmode arising in the problem. Up to our knowledge, this is the first time where modulation is used with this kind of profiles. We do hope that this simplifies the argument.
Open access
2 source records
Stability and Controllability of Differential Equations
While the amount of data produced and accumulated continues to advance at unprecedented rates, protection and concealment of data increase its prominence as a field of scientific study that requires more action. It is essential to protect privacy-sensitive data at every phase; at rest, at run, and while computations are executed on data. The zero-knowledge proof (ZKP) schemes are a cryptographic tool toward this aim. ZKP allows a party to securely ensure the data's authenticity and precision without revealing confidential or privacy-sensitive information during communication or computation. The power of zero-knowledge protocols is based on intractable problems. There is a requirement to design more secure and efficient zero-knowledge proofs. This demand raises the necessity of determining appropriate intractable problems to develop novel ZKP schemes. In this paper, we present a brief outline of ZKP schemes, the connection of these structures to group-theoretic intractable problems, and annotate a list of intractable problems in group theory that can be employed to devise new ZKP schemes.
Healthcare block chains provide an innovative way to store healthcare information, execute healthcare transactions, and build trust for sharing health data in a decentralized open health network environment. Although the healthcare block chain technology has attracted broad interests and attention in industry, government and academia, the security and privacy concerns remain the focus of debate when deploying block chains for information sharing in the healthcare sector from business operation to research collaboration. This paper focuses on the security and privacy requirements for medical data sharing using block chain, and provides a comprehensive overview of security and privacy risks and requirements, along with technical solutions techniques. First, we discuss the security and privacy requirements and attributes required for electronic medical data sharing by deploying the healthcare block chain. Second, we categorize existing efforts into three benchmark block chain use cases for electronic medical information sharing and discuss the technologies to execute these security and privacy properties in the three categories of use cases for healthcare block chain, such as anonymous signatures, attribute-based encryption, zero-knowledge proofs, and verification techniques for smart contract Finally, we discuss other potential block chain application scenarios in healthcare We conjecture that this survey will help healthcare professionals, decision makers, and healthcare service developers to gain technical and intuitive insights into the security and privacy of healthcare block chains in terms of concepts, risks, requirements, development and deployment technologies and systems. Key Words: Asymmetric-key algorithm and hash function, SHA-256 algorithm.
Springtime always sees plenty of activity in the IFST calendar. This year the AGM was at the end of March, where we take necessary and important decisions that support the governance of the Institute, but also where we have the opportunity of acknowledging the changes to our Board. We say thanks to those members who are outgoing and have done so much for IFST and also confirm the appointment and welcome those who are incoming. We have four new trustees joining the Board this year including President Elect Sterling Crew. Much of our engagement is now ‘remote/electronic’ procedures, which included, for the first time this year, the President-Elect ballot and, indeed, the AGM itself. It is good to see the numbers of members who can engage in such important processes increasing as a result – good democratic governance in action! It was also very gratifying to see the strength of the field putting themselves forward for President Elect and I hope this is a sign of the ambition many members have for IFST. Whilst online engagement has many benefits, by the time this volume of the Journal is in print, many of us will have met in Birmingham for the SC22 Conference Lunch and Lecture. Our Spring Conference (SC22) is a much-welcomed staple of our calendar. We took the difficult decision many months ago that holding SC22 itself in person was probably still not a viable proposition, but the opportunity to have a face to face ‘companion’ event seemed like a good option. We hope that accommodating the needs of everyone is something we can continue to do, whilst adapting to the changing environment. The theme of this issue is ‘Future Foods’. Whilst IFST has a major role to play in ensuring the safety and so much more, of today's food, the opportunities to ‘invent our future’ is what gets many of our members out of bed in the morning! I think it is safe to say, that there will be something for everyone in this edition. In talking to members, we know that this publication is one of most valued benefits of IFST membership. So, as we head into summer I wonder if we might indulge in a little fun! Where do you like to read your Journal? If you would like to share, why not join me in posting on the community pages: community.ifst.org/ IFST has elected Sterling Crew as its new President-Elect. Sterling's election was formally noted during IFST's Annual General Meeting on 31 March 2022. Of his appointment, Sterling said: ‘It is a great pleasure and privilege to be elected to be the next President of the Institute of Food Science and Technology, especially as the selection was by my professional peers. The IFST is a fantastic organisation with a marvellous membership at its very heart. I pledge to play my part in adding further value to membership and promoting the organisation's worthy charitable aims. This is an exciting time for IFST as we approach our 60th Diamond Jubilee and with chartership potentially on the horizon. Food science and technology has a major part to play in our country's future in these very challenging times. The food sector has responded by developing innovative solutions and creative products. The role our members play has never been more important.’ Sterling Crew Honorary Fellow and FIFST is an experienced food sector director who currently holds a portfolio of positions including Chair of the Food Authenticity Network. Find out more about Sterling here: ifst.org/president-elect22 Sterling will serve as President- Elect for one year before being automatically elected as President and Chair of the Board of Trustees in 2023 for a term of three years. Meet our Board of Trustees here: ifst.org/meet-board IFST has reviewed its Code of Professional Conduct and its accompanying Disciplinary Procedures that apply to all its members. The Code of Professional Conduct – which members are bound by – remains unchanged but IFST's Board approved minor changes to the Disciplinary Procedures to clarify the use of electronic communications, confidentiality requirements and ensure any member against whom a complaint was upheld had adequate time to lodge an appeal. The updated procedures which came into force on 7 April 2022 are available on our website: ifst.org/about-ifst/professional-conduct In March 2022, IFST was invited to attend and exhibit at IFE Manufacturing at ExCeL London. We were given a stand in the ‘Ask the expert’ zone. IFE Manufacturing is a gigantic exhibition, it's an international food and drink event, which brought together ingredients, packaging, processing and food technology companies to showcase their solutions to manufacturers from all over the UK. The event was an opportunity for the food and drink manufacturing industry to discover, learn and source the latest products from the best suppliers in the market. At IFST we're always looking at new ways to expand our membership and provide a benefit to the whole of the food sector, no matter how big or small the business. We went to IFE to meet new food businesses and to introduce IFST to a new audience who may have not heard of us before. IFE provided IFST with a great opportunity to reconnect with current members, meet potential new industry-based members and understand some of the challenges facing the food sector through the thought-provoking presentations and seminars provided throughout the show. The geographical coverage, category span and quality of the exhibitors was impressive and provided interesting (and tasty!) insights into where food products are heading next. Each day, three or four members of the IFST executive team represented IFST at our stand, including Deborah Kendale, Andrew Gardner, Delia Mertoiu, Sarah Drumm, Mariam Zaki, Daiane Cazuza, Patricia Florit and Robin Leaper. Despite being at the back of the expo, we received a good number of visitors who all had interesting questions for us and lots of enquiries about IFST membership and what it comprises. We were also approached by a lot of new product developers and new businesses looking for support for their endeavours. It was interesting to see the breadth of producers and the strong focus on sustainability, using waste products, innovation and current trends in the food sector. We were delighted to meet our current members at the expo, who came over to our stand each day. The geographical coverage, category span and quality of the exhibitors was impressive and provided interesting (and tasty!) insights into where food products are heading next. I was delighted to be invited by IFE Manufacturing to chair one of the NPD sessions titled From kitchen table to factory floor. This took place on the Innovation Platform on the opening day. It was the first of two back to back sessions examining the NPD process and how to get products from the idea and concept stage through to a fully manufactured product. This session focused on the early development process and highlighted some of the common roadblocks and key considerations that need to be addressed during the initial stages of a development project. Andrew Gardner and Patricia Florit at the IFST stand We drew a large audience (including more IFST members), with every seat in the auditorium taken. There were some great questions from the audience – and we kept going even when the set behind us collapsed mid-session! The panel gave some sound advice about how to get started and how to protect your ideas. We discussed how to make sure products are legal and safe, how to find partners for co-manufacturing and signposted the audience to other resources available to help at this early stage of development. It was a great pleasure to chair this session, and to work with such an experienced and knowledgeable panel of IFST Fellows. One of the many great benefits of being a member of IFST is having access to a wide network of food industry experts. Thank you to IFE Manufacturing for inviting me to take part and for a great show. It was great to finally meet people face to face after two years! There was certainly a buzz about the place. Three big trends were very evident throughout the show: vegan, environment and health. Without a doubt vegan products and meat alternatives are starting to move into mainstream, with new products using mainstream flavours and targeting everyday eating occasions. Many of the companies were keen to talk about their environmental credentials. I saw a cereal carton made from agricultural waste rather than wood pulp, that had the same look and feel as carton. There were also a number of businesses advertising that they use no plastic bags for their snack products. From a hero ingredient perspective, I noticed that seaweed is entering the savoury snack market, highlighting its health benefits. Also, there were a lot of dried fruit snacks as alternatives to more traditional snack products. The panel discussion on The National Food Strategy between the Food Foundation, Compass Group, Guy's and St Thomas’ Foundation and Mission Ventures was notable. Apart from reiterating the importance of and need to take action, the panellists shared the fact that Tesco and JS have agreed to report on how much of the food they sell is ‘healthier’ products. If you missed the panel discussion From kitchen table to factory floor, there is a recording available on the IFE website to watch on demand: web ifemanufacturing.co.uk/seminar-programme Join IFST ifst.org/membership Prof Robin May delivering the SC22 lecture On 25 April, at University College Birmingham, Professor Robin May, Chief Scientific Advisor to the Food Standards Agency, pictured above, gave his talk to a group of members, speakers and friends of IFST at our preconference lunch and lecture. He opened by stating that eating is one of the few universal human behaviours and that trust in food is critical and is underpinned by science. However, science is becoming more complicated and harder to explain, and becomes increasingly challenging especially around foods that are not yet on the market, but will be, in the future. For context, May indicated that food shopping is habitual and purchasing takes on average six to nine seconds. Reading a product label fully would take many minutes and therefore messaging on labels is often not the best way to communicate information. The challenge is to combine a high level of science and communication about risk with a digestible, easy to compute output. He commented that the FSA has a very strong science and evidence based position. Good science communication is critical and risk must be communicated effectively for people to understand this. He highlighted the FSA has a very high trust rating of 75% of people trusting the FSA and nine out of 10 consumers in the UK are confident in the safety of the food they eat. This is partly due to a strong emphasis on clear communication, such as the food hygiene rating system, which 87% of the population are aware of and over 50% state they have used within the last year. In terms of behaviours, people underestimate long term risks, such as those around smoking and obesity, and act accordingly. Using percentages to communicate risks is effective but even more effective is the use of real-world frequencies e.g. ‘one-in-20 people’. Translating these into graphics is attractive but the danger is that nuance and detail can be lost with the example of using just green and red traffic light symbols. We need to change the food system to cope with sustainability and health impacts, for the planet and a healthy population. Part of this is the need to advise people on new foods that are coming to market. Prof May stated that his passion is being ready to communicate these necessary changes to the public and the implications they will have on peoples’ diets and food choices. Examples of new foods were insects, lab grown meat, novel crops e.g. chia seeds and, finally, genetically modified (GM) and genetically edited (GE) crops that are being, or will be introduced, to tackle challenges in agriculture, such as drought tolerance and vitamin yield. We need to be able to communicate the benefits of these foods if they are to be accepted by the general public. May also mentioned changes to packaging types and systems. Both these developments are innovations which the public welcome. However, innovators are viewed with greater suspicion, as they are often perceived as being driven by commercial gain. In terms of opinions and behaviours – people state they are driven by ethical choices, such as animal welfare and sustainability, but are, in reality, driven by price, when it comes to choices and shopping habits. To be effective communicators, we need to work with human behaviour and develop a balance between ethical choices and real world drivers that determine food choice behaviours. Attendees at the lecture Day 1 on The Gap in Consumer Understanding began with Jon Alexander's presentation on The Power of Citizenship. He poignantly began with some food for thought that overuse of the word ‘consumer’ is fundamentally flawed. To reshape the way in which we collectively interact as humans, we must focus on the concept of ‘citizens’. Next, Tom Sheldon at the Science Media Centre delivered a selection of case studies. He advocates for businesses to support senior scientists in engaging with the press, believing this connection is the way forward to help the public separate fact from fiction. The day ended with a panel discussion exploring how we can build trust in consumers. Michelle Patel (FSA) remarked that as scientists we need a ‘shift in how we communicate’. The emerging themes were consistency, courage, honesty and humility. Day 2 on The Gap in Skills and Professional Development began with another panel discussion on new and future skills, with Jacinta George succinctly explaining, ‘the skills we'll need in 20 years need to be developed now’. The group discussed key future skills crucial to the food industry including AI, robotics and green skills, as well as soft skills like resilience, flexibility and compassion. Attendees saw Andras Sebok present a Digital Skills case study using an EIT Food competency framework on Campden BRI Hungary. He discussed ‘Industry 4.0’, which refers to a new phase in the industrial revolution focusing on interconnectivity, automation, machine learning and real-time data. Finally, speakers from CAFRE and Linden Foods presented the positive impacts that apprenticeship schemes have had in Northern Ireland. We heard a personal account from Lewis Connelly, a NPD Technologist at Linden Foods, who started a High Level Apprenticeship (HLA) with CAFRE. Day 3 began with an inspiring presentation on early stage NPD with Sarah Gaunt. The concept of ‘front-end innovation’ was introduced and the developmental stages in the early-product pipeline covering ideation, identification, application, selection and incubation were explored. Following this, Lucia Capogna spoke about cyber-security. Examples of food industry cyber-attacks in recent years were presented and Lucia closed with the final thought that ‘no system is 100% secure’, but with the right knowledge 90% of cyber-attacks can be prevented (see p46). Next, Tom Hollands presented the digital sandwich, a technology that digitises food production processes and creates a ‘golden thread’ from farm to fork, tracing ingredients back to the source. Tom used a fictional example of grey ham identified in a shop sandwich to track an ingredient's journey. Missed SC22? As a paid attendee, you have access to our Conference platform, Whova, for three months where you can watch all of the conference sessions and the lecture recording. Starting from mid-June, as a member of IFST, you can watch all the recordings in our IFST Webinar hub via ifst.org/webinars Across the world 90% of people are meat eaters and global consumption of meat is rising. Meat production is already contributing to potentially catastrophic climate change and if nothing changes, future demands will require impossible amounts of land and water. The ‘Meat the Future’ exhibition considered some of the key findings of the LEAP (Livestock, Environment and People) project, which studied the health, environmental, social and economic impacts of meat and dairy production and consumption. The was a between the University of the Food Institute, and The it was by the Our Our and between and The exhibition was at the general public and presented in a very and IFST members at the exhibition The – exploring the of the meat production and consumption and its The had of meat in between of and of meat on There were also from and visitors who had been to the Meat best as in a lunch and best in to be if other are available for my health, for the for the The a wide of From highlighting how meat consumption is in our to that the public are to its environmental, and ethical credentials. by this exhibit our group discussed the importance of meat in the as another key meat consumption the world The a – of were used to how meat consumption had in the and between and It was a very way of how meat consumption is to and was the in meat consumption in person day in to in and in to in that the in the with the consumption of meat, of personal Meat consumption in has the same at than in the due to requirements and a population. As for the it remains of the meat consumption at a person day in and in the land – agricultural and how they have over the years This exhibit was presented as a set of with and on of the land is currently to agriculture, to how develop from a traditional to the global industry it is how has science to the increasing for In the people of land from the of the the they kept the and on the the used to their There are in the each to in and or of the are as was to more food when but this came at a to as were and to High – the environmental of meat production now more than to for of are for into the and changing grown for animal require more and – for and other resources for human As food they which is more to the environment than contributing to climate The IFST group noted that there was no of the or of meat animal welfare or animal in the As scientists we were to understand more about current into for food – consumers with on the environmental of their food choices is a strong public for choice in what we but in reality, our is already by what businesses us to and how it is and LEAP on the labels of the being food products to their positive or on and As well as consumers more hope that food producers will by developing new products with environmental to find the most effective have been have much environmental impacts of all to and products as much as than most animal products. There is a strong public for choice in what we but in reality, our is already by what businesses us to and how it is and seeds of a new – some of the around meat consumption and including meat has been the for human the world for of of years. evidence some to eating dairy products years Our on animal products such as meat, or dairy for of vitamin that we require for We have also to much more from meat than from are there any health risks in a if we our or it out what are the best to get all the we health – what would an look Our planet has plenty of to all of the people If we make decisions in the coming year, it can even the population of in the for meat is already the environment to its In the we of meat person day This is more than the global how much meat can the planet The on and to this and came with an of person each day, between red meat and – to the we before and factory have with but all on meat than we in the UK. number of including the health report have eating more than our current of foods and than the of and red This report that if we all this, we our and our on the environment. Meat – how science and technology can help us a planet Our to meat and benefit from the it our diets can to us the we need adding to the climate Science and technology the meat industry we thought we is us see why and how we need to do In the a of are already vegan or can more of us learn to a to a more in the exhibition increasing consumption of and the – final We would need agricultural we would need to This land be used to crops for or to to more and use quality and would need more to be used to and other We would use to and in so would the land to quality and our and We more than the from the food system – about a in all from human We see to due to land to and The number of due to such as and some by this is due to the benefits of a healthy to a healthy the positive of diets as well as in the of and some and some FIFST is a Development and Innovation Food and Chair of the IFST Food Innovation and of IFST FIFST is a and in Development and an Innovation and Development to the food industry to the team at University of for IFST. web about the LEAP project, which is by the can be We are delighted to that IFST has its Honorary on for to the of food science and This was made by IFST the Annual General Meeting on 31 March 2022. This is made to or who have made personal to the and of the Institute and to the food science and technology FIFST in food sustainability, and from farm to is of the Food Find out more about here: On I first IFST in the early of my I had no idea that I would one day be joining IFST's of Honorary I often in and in my To be by people I as and to a is I the IFST for this and will this with Food science is more than a sustainability and food I that any can be using food as the and that food on food science in its one can food, so its future has to be through and communication at all by all of us in the This year the of the UK Our has many products that would be in by companies the great and of those to the future of the food market. the time this issue has been the will have their products to the on 7 and the will be at the event at Tesco where will be able to some and meet other industry and from the industry including and Food Institute of Food Science and and Campden For more and We have a new IFST to and to resources to support small and food and food need to healthy and food, and in an and to cope with the challenges of a population. food and the of food throughout the from farm to the The consumption of or foods is increasingly being as an emerging to and the of This evidence on human and the of processing on and of key these food and human have been to and these on therefore more
The stabilization of unmanned aerial vehicles and its orientation in a given direction is provided by the orientation system. One of the important stages in the development of UAV orientation systems is the development of object orientation algorithms. The problem of orientation of objects in the magnetic field is based on the estimation of the discrepancies between the model Bmod and the measured Bmeas components of the Earth's magnetic field. Accordingly, the paper discusses some algorithms related to the orientation of satellites and unmanned aerial vehicles. It is shown that limiting the model to the first 13 harmonics can lead to errors in the representation of the Earth's main magnetic field of about 15 nT. A mathematical proof of this fact is carried out based on the consideration of the equation of an ideal magnetic field meter. The work analytically proves that the Jacobian matrix of the magnetic field measurement vector in the earth's coordinate system has a determinant equal to zero, which means that, having knowledge of the magnetic field measurement vector H-1, it is impossible to uniquely determine the vector of the orientation angles of the meter {f, o, y }t-. Thus, the paper shows an algorithm for calculating the orientation angles depending on the values of the measured and model values of the Earth's magnetic field.
Agriculture is leaving a profound footprint on the Earth. With field surveys and modeling techniques, researchers are exploring how to make agricultural landscapes less threatening to biodiversity. In Bokito, Cameroon, a forest transitions to farmland. Photograph: Mokhamad Edliadi/CIFOR. In Andhra Pradesh, India, Iris Berger removes her shoes before wading into a rice paddy. As water sloshes around her knees, she keeps a wary eye out for the occasional cobra. But mostly, Berger's eyes and ears are fixed on other creatures: birds. Andhra Pradesh, a state in the country's southeast, is in the middle of a major agricultural shift to using locally sourced inputs rather than chemical pesticides and fertilizers. The hope is that the practice, known as zero budget natural farming (ZBNF), will be easier on the farmers' budgets and also on the region's natural resources and wildlife. Berger, a conservation scientist working on her PhD at the University of Cambridge, is surveying birds on farms and natural areas to learn whether ZBNF could prove one solution to a problem researchers and farmers are contending with the world over: how to increase food production without losing biodiversity. The Earth's biodiversity is in steep decline. Between 1970 and 2016, populations of bird, reptile, mammal, fish, and amphibian species fell an average of 68%, according to the World Wildlife Fund's Living Planet Report 2020. The biggest driver threatening endangered species is often habitat loss, says Christopher Crawford, a PhD candidate in the Science, Technology, and Environmental Policy Program in Princeton University's School of Public and International Affairs. “Usually, the biggest driver of habitat loss is land-use change. And usually, that is coming from agriculture.” But the need for food grows. Accounting for changes in climate, global food demand could increase between 30% and 62% from 2010 to 2050, according to a meta-analysis by Michiel van Dijk, of Wageningen Economic Research in the Netherlands, and colleagues in a July 2021 Nature Food issue. Faced with this challenge, Crawford, Berger, and others are using on-the-ground surveys and sophisticated models to strategize about where it is best to farm and where it is best to let nature be. The work points to ways forward” for example, focusing on which uncultivated regions are species poor but could yield good crops and which crops, with improved farming strategies, could produce enough on existing farms. But the work also raises questions, from how to engage policymakers to what the definition of biodiversity really is. Agriculture has left a profound imprint. Around 38% of the Earth's land surface is now covered by cropland or livestock grazing areas, according to the Food and Agriculture Organization of the United Nations (FAO). In Brazil, a smallholder farmer harvests oil palm. Photograph: Miguel Pinheiro/CIFOR. In a May 2021 study in Nature Communications, Karina Winkler, of Wageningen University and Research in the Netherlands, and colleagues estimated that the global agricultural land area increased by around 2 million square kilometers between 1960 and 2019 alone. A January 2022 study in Nature Food by the University of Maryland's Peter Potapov and others found that the annual rate of global cropland expansion has nearly doubled over the past two decades. As farms expand, wilderness retreats. Nearly 90% of global deforestation between 2000 and 2018 occurred because of the expansion of cropland and livestock grazing areas, according to the FAO. In a December 2020 report in Nature Sustainability, David Williams, of the University of Leeds, in the United Kingdom, and colleagues identified 1280 vertebrate species projected to lose a quarter or more of their habitat to agricultural expansion by the year 2050 if policy changes fail to make food production less costly to biodiversity. This biodiversity loss presents an issue, not only for the environment but for farming, because many crops depend on ecosystem services that require biodiversity. Agricultural intensification reduces the abundance and diversity of pollinators and the natural enemies of agricultural pests, explains ecologist Matteo Dainese, of Eurac Research's Institute for Alpine Environment, in Italy. In 2019, Dainese, then at the University of Würzburg in Germany, and colleagues published a study in Science Advances that compiled data on pollinator and pest control species, as well as evidence of pollination and pest control services, from 89 previously published studies covering 1475 agricultural fields across the globe. They found that, as agricultural area around a particular field increased, species richness” the numbers of species providing pollination and pest control services to the field” declined. Successful pollination and pest control depended not only on a species's overall abundance but also on this species's richness. In fact, greater agricultural expansion around a field indirectly resulted in lower yields because of the decrease in the number of species. “It is important to maintain biodiversity,” says Dainese. To protect biodiversity, it helps to know which land is likely to be cleared next” and for what cause. Maybe a new soybean field is an isolated development. Or maybe it is the start of a farming trend that could sweep into neighboring forests. “We wanted to look at the specific crops to identify those crops that pose the most threat in which regions,” says conservation economist Roman Carrasco, of the National University of Singapore. Carrasco and colleagues developed a model based on the von Thünen model, which predicts that land will be allocated to whatever use generates the highest net revenue. The team compiled published data related to potential earnings across the globe for 17 important crops, including wheat, soybean, and coffee. They entered that data into the model to predict which crops were likely to spread where by 2050. “We divide the world into cells,” explains Carrasco. “And then we say, in this cell, what is the potential for production for each crop? What are the [crop] prices? How far away from the cities [is the cell], and how much would it cost to bring [the harvest] to the city?” The team also included data on the distance to the nearest farm growing the same crop. “It's hard to have a completely new crop in a new place,” explains Carrasco, because there is not the know-how for growing it. The model predicted that 260 million hectares of land has high potential to be converted into cropland by 2050. Roughly 80% of this land is forested. In Borneo, natural habitat is being logged to make way for oil palm. Photographs: L. Roman Carrasco/National University of Singapore. By incorporating political stability and governing style into the model, the team also learned that conflict within countries appears to be a major factor limiting agriculture's advance into some of the planet's most biodiverse habitats. Coconut, for example, is poised to expand in the Democratic Republic of the Congo. Carrasco and colleagues posit that the main factor holding this and other crops back there is political conflict, which discourages foreign investment. The same is true for other countries facing political instability, such as Venezuela and Angola. Some growers in Andhra Pradesh, India, use conventional farming techniques to raise maize but with patches of natural habitat throughout. Photograph: Iris Berger/University of Cambridge. “What we think is that, when that political instability is resolved, these areas will be under big threat of conversion from crops,” says Carrasco. He hopes that, by identifying this risk now, conservation organizations can engage with governments in these regions to develop careful plans for where to expand agriculture and where to protect wildlife. The study also showed that, if growers could reach the greatest possible yields for their regions, the need for additional farmland by 2050 would drop by 27%. Closing this yield gap, Carrasco estimates, would prevent 20% of species extinctions for birds and 6% for mammals. Encouraging farming practices that raise the productivity of three crops in particular” rice, soybean, and wheat” would be especially impactful, says Carrasco. “The demand is massive for those three, and they are in areas that have a lot of biodiversity.” This potential to save natural landscapes by increasing production on existing farmland is at the heart of many debates about reconciling food demand and biodiversity. Since the early 2000s, conservation scientist Andrew Balmford, of the University of Cambridge, in the United Kingdom, has explored the effects of what he calls land sharing versus land sparing. Land sharing makes agricultural land more hospitable to wildlife through practices such as incorporating hedgerows and ponds and limiting the use of chemicals. But land sharing can produce lower yields, requiring more farmland, explains Balmford. “You make the farm friendlier for wildlife; that's great. But you're reducing your production, and that simply means the problem is going to leak somewhere else.” Alternatively, land sparing aims to increase yield even at a cost to biodiversity within agricultural areas, which can free up space for natural habitats elsewhere. Balmford's team first explored the impact of these two approaches using data on the population densities of bird and tree species sampled across Ghana and India. The sampling sites spanned high-producing monoculture to more low-yielding fields of diverse crops interspersed with forest. For each species in each country, the researchers studied the relationship between the abundance of individual species and crop yield. They then used those relationships to project whether each species would be better off if food demands were met through land sparing, land sharing, or some intermediate. The research, reported in Science in 2011, suggests that most bird and tree species are negatively affected by agriculture, and the majority of these species are sensitive to even low-yield farming. Land sparing, then, would allow for greater population sizes for most bird and tree species across the landscape as a whole. Balmford and colleagues continued this research in other regions with additional species, looking to see if the findings held. “We had people looking at grasses and sedges and daisies and dung beetles, and we were still getting the same broad pattern,” says Balmford, noting that the pattern held for the majority of species in each taxon and in every location. In a 2021 review in the Journal of Zoology, which includes work from his own group and others, Balmford reports that, of over 2500 species studied, over three-quarters survive better without agriculture, and of those, the large majority maintain greater population sizes under land sparing. Balmford says that his findings have been criticized by those who equate higher yields under land sparing with unsustainable farming inputs, including chemical fertilizers and pesticides. “We don't think it needs to be that at all,” says Balmford, noting that the yield could also increase through additional labor or farming knowledge and under certain traditional farming practices. Berger was struck by Balmford's findings and wondered whether” if land sparing really is better for biodiversity” there could be ways to ramp up the yield sustainably. “There's no use in increasing the yield, and then, in 10 years' time, the soil is degraded,” says Berger. She wondered whether the ZBNF movement gaining momentum in Andhra Pradesh could be part of the answer. ZBNF began taking hold in Andhra Pradesh as early as 2016, says agricultural scientist Zakir Hussain, who leads science and research for the Farmer Empowerment Organisation (RySS), the government-supported non profit responsible for helping farmers in Andhra Pradesh transition to ZBNF. In 2018, the government of Andhra Pradesh announced a push to transition all of the state's farms to ZBNF in a bid to improve the livelihoods of smallholder farmers and to restore the region's biodiversity and ecosystem services. Growers began eschewing synthetic pesticides and fertilizers in favor of more cost-effective and sustainable options, such as managing pests with botanical extracts or creating perches for insect-eating birds. Today, Hussain says that about 800,000 farmers in Andhra Pradesh practice ZBNF, which the government now refers to as community managed natural farming. Anecdotal evidence that ZBNF can match or even surpass conventional farm yields is mounting, and the practice is spreading quickly. ZBNF farmers become “ambassadors,” says Hussain. “They spread natural farming practices to other farmers.” Scientific research exploring ZBNF practices is just beginning to emerge. In a February 2022 issue of the journal Sustainability, Hussain and colleagues described a field experiment at study sites across Andhra Pradesh in which they found no difference in yield between plots managed with conventional and those managed with ZBNF practices for a variety of crops. Berger wants to know how ZBNF affects birds. She wonders whether the practice may make farms more habitable for birds while also increasing yields so that more wild habitats can be spared. She surveys the density and diversity of avian species on ZBNF and conventional farms, as well as in forests untouched by agriculture. She also records the proportions of natural habitat nested within the farmland. Ultimately, Berger, who counts Balmford as one of her dissertation advisors, will enter this data into a mathematical model that will optimize the agricultural landscape to meet food production goals while maximizing the density for each bird species. She will learn the ideal amount of spared habitat versus farmed land, the optimum proportion of ZBNF versus conventional farms, and the most effective proportion of natural habitat patches within farmland. The results, she says, could suggest a combination of different approaches in different areas. Maybe in some places, for example, ZBNF produces lower yields, so some proportion of conventional farms are required to spare the natural habitat that specific bird species require. But perhaps these conventional farms need to include some optimum number of habitat patches to maintain pollinators and other ecosystem services critical for their yield. “It's very complex and probably very case specific,” says Berger. Researchers are also using models to pinpoint where, in an ideal world, farming could expand at the least cost to biodiversity. But the work hinges on estimating one variable that is especially difficult to pin down: biodiversity itself. Biodiversity is the variety of life on Earth. This variety exists at different scales, such as whole ecosystems, species, or genes within species. Researchers recording biodiversity simply cannot count everything. So they make choices. Some may tally all vertebrate or plant species or give higher weight to endangered species or use only birds or another representative group. Many combine several of these measures into a single biodiversity index. When Crawford began reading land prioritization studies, he recognized that researchers often measure biodiversity in different ways. “All valid and defensible methods,” he says. But he wanted to understand how seemingly small differences between methods ultimately influence land-planning recommendations. Crawford began with a land-use model called agroEcoTradeoff, previously developed by colleagues at Princeton and elsewhere. He used this model to project where to convert land to farmland in Zambia to minimize biodiversity loss while meeting crop production needs in this country with a rapidly growing population and economy. Lilac-breasted roller (Coracias caudatus) at South Luangwa National Park, Zambia (l). Researchers are using models to determine where in Zambia the land could be farmed with minimal biodiversity loss. Photograph: Hans Hillewaert, CC BY-SA 4.0. Two male Phyllomedusa rohdei frogs in the Atlantic Forest in Bahia, Brazil. Some 85% of this forest has been cleared for agriculture, pasture, timber plantations, and cities. It remains home to 2200 species of fauna and 20,000 species of plants. Photograph: Renato Augusto Martins, CC BY-SA 4.0. Crawford ran the model with four previously published biodiversity indices and, each time, received different recommendations for where to expand agriculture. An index focused on vertebrate species richness with additional consideration given to species' range sizes, for example, suggested that agricultural expansion would be best placed in the southwestern portion of the country. Meanwhile, an index focused on how rare, intact, and well-protected different vegetation types are instead suggested that farmland should expand along the eastern portion of the country. Indeed, when comparing recommendations for where to expand agriculture between pairs of indices, the average overlap was only around 2%. The team then developed a series of their own indices so that they could systematically vary different components to understand what exactly causes biodiversity indices to return such divergent recommendations. They found that focusing on different groups of animals could change the recommendations dramatically. Bird diversity in for example, was least by agriculture in the would be better off if agriculture into the and affected the recommendations such as the of the data included and how much weight was given to range when species richness. the of whether to combine different biodiversity measures by taking the versus the could the recommendations in ways. for these of prioritization to be in about land-use and land-use researchers need to be very careful and about how they are biodiversity and about the that they are says As researchers for the best possible between farmland and biodiversity they also the of this ideal landscape into yields the space that farmland says Balmford. “It will to if look at global over for most in most But it The as Balmford explains in his 2021 Journal of is that a in yield could lower and so requiring more yields could also increase which that into more land Land sparing, then, best when increased yields are by policy measures at biodiversity, such as land-use and to the area covered by agriculture. such as this field in biodiversity, including the biodiversity of species to farming. Photograph: Some growers use such as this one on a to and increase biodiversity. Photograph: of Agriculture But these policy changes require to the of biodiversity and the of potential issue is that the research in this field is focused on biodiversity across the but the researchers are often based in and are for research to be by people who the these says this research to have an says Carrasco, should be from the So when are your research, should with the of the country and to understand the they to also need measures of biodiversity and between biodiversity and of the World in Cambridge, in the United Kingdom, and colleagues in a 2021 in Nature that countries need a biodiversity index the is a measure of and colleagues say, the would be a measure of a biodiversity The would be using a that of biodiversity, as well as that biodiversity to from to the of including and The is still in a says scientist and landscape ecologist of the National for and of Biodiversity in a on the is an for while researchers in South and develop their has been biodiversity data to government and organizations for over two now, says But as a single the of biodiversity in the country, it is really difficult to because have to use all of these of says The hope is that an will a for biodiversity over that a policy change will work also “We need evidence for the governments to and bring policy says Hussain. And the same for livelihoods depend on these had farmers that growing crops out of the year could increase production and also protect the So the says Hussain, farmers are the Balmford spreading how to meet needs at least cost to Journal of Crawford of in biodiversity indices used for land-use A global for crop Science Advances Carrasco of conversion risk from crop
Open access
Sustainable Development and Environmental Policy
Conservation, Biodiversity, and Resource Management
Igor A. Kalmykov, В Ш Мухаметшин, K T Tyncherov, M V Selivanova
Abstract Low-earth orbit (LEO) satellite communication systems must have anti-jam property, which is based on information, structural and energy secrecy as well as immunity to jamming. One of the directions associated with increasing information secrecy is based on the use of a satellite identification system. This system is designed to prevent the imposition of foreign content on the subscriber through the use of an authentication protocol built on proof with zero knowledge. To reduce the time of applicant identification, a number of works propose to use modular codes (MC), which allow parallelizing the computational process in the protocol. It is known that MCs can improve the fault tolerance of the identification system since they are able to eliminate the consequences of faults and failures during operation. However, they can also be used to improve the immunity of LEO satellite communication systems to jamming. Thus, the use of a unified algebraic system when constructing MCs capable of correcting errors caused not only by faults and failures during the operation of the identification system but also by interference in the communication channel will enable to abandon concatenated codes. Therefore, the development of a method for constructing a modular turbo code for an anti-jam satellite authentication system is an urgent task.
Mishri Saleh Al-Marshoud, Ali H. Al‐Bayatti, Mehmet Sabır Kiraz
Security and privacy in vehicular ad hoc networks (VANETs) are challenging in terms of Intelligent Transportation Systems (ITS) features. The distribution and decentralisation of vehicles could threaten location privacy and confidentiality in the absence of trusted third parties (TTP)s or if they are otherwise compromised. If the same digital signatures (or the same certificates) are used for different communications, then adversaries could easily apply linking attacks. Unfortunately, most of the existing schemes for VANETs in the literature do not satisfy the required levels of security, location privacy, and efficiency simultaneously. This paper presents a new and efficient end-to-end anonymous key exchange protocol based on Yang et al. 's self-blindable signatures. In our protocol, vehicles first privately blind their own private certificates for each communication outside the mix-zone and then compute an anonymous shared key based on zero-knowledge proof of knowledge (PoK). The efficiency comes from the fact that once the signatures are verified, the ephemeral values in PoK are also used to compute a shared key through an authenticated Diffie-Hellman key exchange protocol. Therefore, the protocol does not require any further external information to generate a shared key. Our protocol also does not require an interference with the Roadside Units or Certificate Authorities, and hence can be securely run outside the mixed-zones. We demonstrate the security of our protocol in an ideal/real simulation paradigm. Hence, our protocol achieves secure authentication, forward unlinkability, and accountability. Furthermore, the performance analysis shows that our protocol is more efficient in terms of computational and communication overheads compared to existing schemes.
This dissertation is composed of two main research projects. The first, which was conducted with my adviser Xiaoming Song as a continuation of her work with with her previous student Nathan Anderson-Stahl. In that chapter, we consider a class of general backward stochastic differential equations and backward doubly stochastic differential equations to provide a standard method to prove the existence and uniqueness of the Lp solutions and to obtain the Lp estimates for the solutions. The other project was conducted in collaboration with Josh McGinnis and corresponds to the second chapter in which we provide a physical zero knowledge proof for the popular app game Flow Free. We then show that the methodology can be extended to provide zero knowledge proofs for the related graph problems of the paired many-to-many disjoint covering path problem, the unpaired many-to-many disjoint covering path problem and Hamiltonian cycles.
How to achieve secure content distribution and accountability in information-centric networking (ICN) is a crucial problem. Subscribers need to verify whether the data came from a reliable source, rather than from a spoofing adversary. Public key cryptography was introduced to achieve a method of authentication that binds the data packet to its owner. In existing prototypes, PKIs, identity-based signatures (IBSs) and recommendation networks are the common schemes used to ensure the authenticity and availability of public keys. However, CA-based PKIs and KGC-based IBSs have been proven to be weak when it comes to resisting security attacks, with recommendation networks being too complex to deploy. In this respect, we designed a novel distributed authentication model as a secure scheme to support public key cryptography. Our model establishes a decentralized public key infrastructure by combining the smart contracts of blockchain and optimized zero-knowledge proof-verifiable presentations by utilizing the DID project, which realizes the management of public key certificates through blockchain and ensures the authenticity and availability of public keys in decentralized infrastructure. Our scheme fundamentally solves the issues of security and feasibility in existing schemes and provides a more scalable solution with respect to authenticating data sources. An experiment demonstrated that our proposal is 20% faster than the original zero knowledge proof scheme in registration.
Open access
Caching and Content Delivery
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
When trying to fit a deep neural network (DNN) to a $G$-invariant target function with $G$ a group, it only makes sense to constrain the DNN to be $G$-invariant as well. However, there can be many different ways to do this, thus raising the problem of ``$G$-invariant neural architecture design'': What is the optimal $G$-invariant architecture for a given problem? Before we can consider the optimization problem itself, we must understand the search space, the architectures in it, and how they relate to one another. In this paper, we take a first step towards this goal; we prove a theorem that gives a classification of all $G$-invariant single-hidden-layer or ``shallow'' neural network ($G$-SNN) architectures with ReLU activation for any finite orthogonal group $G$, and we prove a second theorem that characterizes the inclusion maps or ``network morphisms'' between the architectures that can be leveraged during neural architecture search (NAS). The proof is based on a correspondence of every $G$-SNN to a signed permutation representation of $G$ acting on the hidden neurons; the classification is equivalently given in terms of the first cohomology classes of $G$, thus admitting a topological interpretation. The $G$-SNN architectures corresponding to nontrivial cohomology classes have, to our knowledge, never been explicitly identified in the literature previously. Using a code implementation, we enumerate the $G$-SNN architectures for some example groups $G$ and visualize their structure. Finally, we prove that architectures corresponding to inequivalent cohomology classes coincide in function space only when their weight matrices are zero, and we discuss the implications of this for NAS.
The assignment problem is an essential problem in many application fields and frequently used to optimize resource usage. The problem is well understood and various efficient algorithms exist to solve the problem. However, it was unclear what practical performance could be achieved for privacy preserving implementations based on multiparty computation (MPC) by leveraging more efficient solution strategies than MPC based simplex solvers for linear programs. We solve this question by implementing and comparing different optimized MPC algorithms to solve the assignment problem for reasonable problem sizes. Our empirical approach revealed various insights to MPC based optimization and we measured a significant (50x) speedup compared to the known simplex based approach. Furthermore, we also study the overhead introduced by making the results publicly verifiable by means of non-interactive zero-knowledge proofs. By leveraging modern proof systems we also achieve significant speedup for proof and verification times compared to the previously proposed approaches as well as compact proof sizes.
Abstract Succinct non-interactive arguments (SNARGs) enable verifying NP statements with lower complexity than required for classical NP verification. Traditionally, the focus has been on minimizing the length of such arguments; nowadays, researchers have focused also on minimizing verification time, by drawing motivation from the problem of delegating computation. A common relaxation is a preprocessing SNARG, which allows the verifier to conduct an expensive offline phase that is independent of the statement to be proven later. Recent constructions of preprocessing SNARGs have achieved attractive features: they are publicly-verifiable, proofs consist of only O (1) encrypted (or encoded) field elements, and verification is via arithmetic circuits of size linear in the NP statement. Additionally, these constructions seem to have “escaped the hegemony” of probabilistically-checkable proofs (PCPs) as a basic building block of succinct arguments. We present a general methodology for the construction of preprocessing $$\text{ SNARG } $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mspace/><mml:mtext>SNARG</mml:mtext><mml:mspace/></mml:mrow></mml:math> s, as well as resulting new efficiency features. Our contribution is threefold: (1) We introduce and study a natural extension of the interactive proof model that considers algebraically-bounded provers; this new setting is analogous to the common study of algebraically-bounded “adversaries” in other fields, such as pseudorandomness and randomness extraction. More concretely, in this work we focus on linear (or affine) provers, and provide several constructions of (succinct two-message) linear interactive proofs (LIPs) for NP. Our constructions are based on general transformations applied to both linear PCPs (LPCPs) and traditional “unstructured” PCPs. (2) We give conceptually simple cryptographic transformations from LIPs to preprocessing SNARGs, whose security can be based on different forms of linear targeted malleability (implied by previous knowledge assumptions). Our transformations convert arbitrary (two-message) LIPs into designated-verifier SNARGs, and LIPs with degree-bounded verifiers into publicly-verifiable SNARGs. We also extend our methodology to obtain zero-knowledge LIPs and SNARGs. Our techniques yield SNARGs of knowledge and thus can benefit from known recursive composition and bootstrapping techniques. (3) Following this methodology, we exhibit several constructions achieving new efficiency features, such as “single-ciphertext preprocessing SNARGs.” We also offer a new perspective on existing constructions of preprocessing SNARGs, revealing a direct connection of these to LPCPs and LIPs.