Zero-Knowledge Proof-of-Identity from trusted public certificates (e.g.,\nnational identity cards and/or ePassports; eSIM) is introduced here to\npermissionless blockchains in order to remove the inefficiencies of\nSybil-resistant mechanisms such as Proof-of-Work (i.e., high energy and\nenvironmental costs) and Proof-of-Stake (i.e., capital hoarding and lower\ntransaction volume). The proposed solution effectively limits the number of\nmining nodes a single individual would be able to run while keeping membership\nopen to everyone, circumventing the impossibility of full decentralization and\nthe blockchain scalability trilemma when instantiated on a blockchain with a\nconsensus protocol based on the cryptographic random selection of nodes.\nResistance to collusion is also considered.\n Solving one of the most pressing problems in blockchains, a zk-PoI\ncryptocurrency is proved to have the following advantageous properties:\n - an incentive-compatible protocol for the issuing of cryptocurrency rewards\nbased on a unique Nash equilibrium\n - strict domination of mining over all other PoW/PoS cryptocurrencies, thus\nthe zk-PoI cryptocurrency becoming the preferred choice by miners is proved to\nbe a Nash equilibrium and the Evolutionarily Stable Strategy\n - PoW/PoS cryptocurrencies are condemned to pay the Price of Crypto-Anarchy,\nredeemed by the optimal efficiency of zk-PoI as it implements the social\noptimum\n - the circulation of a zk-PoI cryptocurrency Pareto dominates other PoW/PoS\ncryptocurrencies\n - the network effects arising from the social networks inherent to national\nidentity cards and ePassports dominate PoW/PoS cryptocurrencies\n - the lower costs of its infrastructure imply the existence of a unique\nequilibrium where it dominates other forms of payment\n
As Electric Vehicles (EVs) are becoming widely available, their secure management is crucial to fully enable their potential. For instance, for convenient charging, they may require quick authentication with the charging stations while they are on the go. As charging is frequently needed, exposing one's charging frequency to the stations may risk the exposure of privacy for the EV driver. Therefore, a mechanism is needed to hide EV information. In this paper, we propose using zero-knowledge proofs to achieve this goal. While zero-knowledge proofs can provide anonymous authentication, they require computation for generation of witnesses. Therefore, we assess the overhead of generating a witness and proof computation at the resource constrained on-board units (OBUs) which are deployed on EVs that utilize wireless communications for scheduling. The results indicate that computation overhead is minimal and can be delployed on resource contrained devices.
User's digital identity information has privacy and security requirements. Privacy requirements include confidentiality of the identity information itself, anonymity of those who verify and consume a user's identity information and unlinkability of online transactions which involve a user's identity. Security requirements include correctness, ownership assurance and prevention of counterfeits of a user's identity information. Such privacy and security requirements, although conflicting, are critical for identity management systems enabling the exchange of users' identity information between different parties during the execution of online transactions. Addressing all such requirements, without a centralized party managing the identity exchange transactions, raises several challenges. This paper presents a decentralized protocol for privacy preserving exchange of users' identity information addressing such challenges. The proposed protocol leverages advances in blockchain and zero knowledge proof technologies, as the main building blocks. We provide prototype implementations of the main building blocks of the protocol and assess its performance and security.
The notion of risk plays a central role in economics, finance, health, psychology, law and elsewhere, and is prevalent in managing challenges and resources in day-to-day life. In recent work, Duncan Pritchard (2015, 2016) has argued against the orthodox probabilistic conception of risk on which the risk of a hypothetical scenario is determined by how probable it is, and in favour of a modal conception on which the risk of a hypothetical scenario is determined by how modally close it is. In this article, we use Pritchard's discussion as a springboard for a more wide-ranging discussion of the notion of risk. We introduce three different conceptions of risk: the standard probabilistic conception, Pritchard's modal conception, and a normalcy conception that is new (though it has some precursors in the psychological literature on risk perception). Ultimately, we argue that the modal conception is ill-suited to the roles that a notion of risk is required to play and explore the prospects for a form of pluralism about risk, embracing both the probabilistic and the normalcy conceptions. We take the view that a risk judgment always implicates a body of evidence, which we refer to as the background evidence. In cases where the background evidence is not made explicit, we take it to be supplied by the context of utterance and, in typical cases, to be the evidence possessed by the one making the judgment. That is, we are inclined towards a contextualist semantics for utterances such as 3 and 4, on which their truth conditions feature an evidence parameter, the value of which is fixed by the context. The semantics of such utterances is not, however, our primary concern here. As well as making categorical risk judgments such as the above, we often make comparisons. While we may judge that the risk of a plane crash is very low, we may also judge that there is a higher risk of a car crash on the way to the airport. As well as judging that there's a high risk of food poisoning at a particular restaurant, we might also judge that there is a lower risk of food poisoning at the restaurant next door. Moreover, while we often speak about the riskiness of feared events, such as plane crashes, food poisoning, etc., we can also assess the risk of states of affairs. For instance, before drilling into the wall of a 1970s West Australian house, one might assess the risk that the wall contains asbestos, or jurors in a criminal trial, when contemplating a guilty verdict, might consider the risk that the defendant is innocent, or a mountaineer may ponder the risk that the snow conditions are unfavourable for a climb. Here, we treat propositions as the primary bearers of risk, with the riskiness of an event or state of affairs corresponding to the riskiness of the proposition that the event occurs, or the state of affairs obtains. As well as making judgments about the risk of specific events and states of affairs, people also assess the risk of activities or decisions, saying things like ‘Drilling into this wall is risky’, ‘It would be risky to attempt a climb under these conditions’. These judgments are important to understanding the connections between risk and decision making but we put them to one side here. According to the probabilistic of risk, the risk of a proposition is determined by the of higher the the higher the risk. this the risk of is higher the risk of in is more probable is. The be as the background evidence. 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A phishing attack is one of the severe threats to the smartphone users. As per the recent lookout report, mobile phishing attack is increasing 85% year to year and going to become a significant threat to the smartphone users. This social engineering attack attempts to get the user’s password by disguising as trusted service provider. Most of the smartphone users are using the Internet services outside of the traditional firewall. Cloud-based documents are one of the primary targets of this phishing attack in mobile cloud computing. Also, most smartphone users are using the cloud storage in their device. To secure against this password attack in a mobile cloud environment, we propose a new authentication scheme to provide novel security to the mobile cloud services. This scheme will verify the user and service provider without transmitting the password using the Zero-knowledge proof based authentication protocol. Moreover, the proposed scheme will provide mutual authentication between the communication entities. The effectiveness of proposed scheme would be verified using protocol verification tool called Scyther.
Liang Wang, Gilad Asharov, Rafael Pass, Thomas Ristenpart · 5 authors
We explore how to build a blind certificate authority (CA). Unlike conventional CAs, which learn the exact identity of those registering a public key, a blind CA can simultaneously validate an identity and provide a certificate binding a public key to it, without ever learning the identity. Blind CAs would therefore allow bootstrapping truly anonymous systems in which no party ever learns who participates. In this work we focus on constructing blind CAs that can bind an email address to a public key. To do so, we first introduce secure channel injection (SCI) protocols. These allow one party (in our setting, the blind CA) to insert a private message into another party's encrypted communications. We construct an efficient SCI protocol for communications delivered over TLS, and use it to realize anonymous proofs of account ownership for SMTP servers. Combined with a zero-knowledge certificate signing protocol, we build the first blind CA that allows Alice to obtain a X.509 certificate binding her email address alice@domain.com to a public key of her choosing without ever revealing ``alice'' to the CA. We show experimentally that our system works with standard email server implementations as well as Gmail.
Online advertising is a popular business model where advertisers can deliver promotional marketing messages to their potential consumers via Ad brokers. However, as the proxy between advertisers and customers, a malicious Ad broker could arbitrarily fabricate the advertising rates to overcharge advertisers, which causes unnecessary financial loss. To deal with this issue, we propose a publicly verifiable and fair online advertising scheme. Specifically, a proof-of-downloading (PoD) protocol is first designed based on the zero-knowledge succinct non-interactive argument of knowledge (zk-SNARK), to help the customer generate a unique acknowledgment for downloading the Ad; the acknowledgment will then be published to both the advertiser and the Ad broker such that anyone can verify the acknowledgment to guarantee the fairness and transparency of online advertising. Moreover, as long as the customer's private key is not leaked, our scheme can resist the collusion attack, i.e., the Ad broker and the customer collude with each other to deceive the advertiser, which has not been addressed in previous works. Finally, we evaluate the performance of the proposed scheme to demonstrate its computational efficiency.
Raphael Matile, Bruno Rodrigues, Eder J. Scheid, Burkhard Stiller
Democracy in the digital age has attracted a lot of public attention in recent years. However, bringing the human right of secrecy in voting to electronic systems is difficult. Properties, such as the possibility of verifying universally that any vote counted was indeed carrying the decision made by a voter, are often conflicting and a trade-off must be found. This paper proposes a blockchain-based electronic voting system providing explicitly cast-as-intended verifiability. By using a non-interactive zero-knowledge proof of knowledge any voter can verify that his or her encrypted vote represents the decision voted for while maintaining at the same time the secrecy of the ballot. In addition, any required cryptographic material can be generated in linear time with respect to the number of voters, making the system suitable for large scale elections, thus scalable.
The development of quantum computers has urged the cryptographic community to prepare cryptographic primitives for the eventual arrival of the post‐quantum world. To this end, the authors study the witness indistinguishability (WI) and witness hiding (WH) of proof systems against quantum adversaries. They give formal definitions of quantum WI (QWI) and quantum WH (QWH), present proof systems satisfying these definitions, and specify a condition under which QWI implies QWH. Regarding the non‐interactive proof systems, they prove that, even if a common reference string is used to generate polynomially many non‐interactive proofs, the QWI is still preserved, while quantum zero‐knowledge has no such beneficial property. To show the strength of QWI, they present two applications of them. First, they prove that the construction proposed by Feige et al . that transforms any non‐interactive bounded zero‐knowledge proof system to a general one is also feasible against quantum adversaries. Second, they construct a quantum‐secure signature scheme in the CRS model, which is existentially unforgeable against quantum adversaries and remains secure even if a common random string is used to sign polynomially many messages.
The Internet of Things (IoT) is very attractive because of its promises. However, it brings many challenges, mainly issues about privacy preservation and lightweight cryptography. Many schemes have been designed so far but none of them simultaneously takes into account these aspects. In this paper, we propose an efficient attribute-based credential scheme for IoT devices. We use elliptic curve cryptography without pairing, blind signing, and zero-knowledge proof. Our scheme supports block signing, selective disclosure, and randomization. It provides data minimization and transaction unlinkability. Our construction is efficient since smaller key size can be used, and computing time can be reduced. As a result, it is a suitable solution for IoT devices characterized by three major constraints, namely low-energy power, small storage capacity, and low computing power.
Abrar O. Alkhamisi and Fathy Alboraei Abrar O. Alkhamisi and Fathy Alboraei
In recent years, the Internet of Things (IoT) plays a vital role in our daily activities .Owing to the increased number of vulnerabilities on the IoT devices, security becomes critical in the untrustworthy IoT environment. Access control is one of the top security concerns, however, implementing the traditional access control mechanisms in the resource-constrained nature of the IoT devices is a challenging task. With the emergence of blockchain technology, several recent research works have focused on the adoption of blockchain in IoT to resolve the security concerns. Despite, integrating the blockchain in the resource-constrained IoT context is difficult. To overcome these obstacles, the proposed work presents a privacy-aware IoT security architecture to ensure the access control based on Smart contract for resource-constrained and distributed IoT devices. The design of the proposed architecture incorporates three main components such as the contextual blockchain gateway, decentralized revocation manager, and non-interactive zero-knowledge proof based validation. By modeling the contextual blockchain gateway, the proposed architecture ensures the dynamic authentication and authorization based on the contextual information and access policies. Instead of integrating the blockchain technology into resource-constrained IoT devices, the smart contract-based distributed access control system with the contextual blockchain gateway provides the scalable solution. With the association of decentralized revocation manager in the smart contract, it prevents the resource access from the unauthorized users by dynamically generating and updating the revoked user list of all the nodes in the smart contract. Moreover, the proposed architecture employs the non-interactive zeroknowledge proof cryptographic protocol to ensure the transaction privacy within the smart contract. Consequently, it maintains the trade-off between the transparency and privacy while ensuring the security for the distributed IoT environment.
The atmosphere at the 5th Annual Immuno-Oncology 360° (IO360°) Conference, which took place on February 6–8 at the Crowne Plaza Times Square in New York City, was truly collaborative. Co-chaired by Axel Hoos, MD, PhD (GSK), James Gulley, MD, PhD (National Cancer Institute [NCI]), and Andrew Baum, MD (Citi), the conference featured almost 100 speakers and 10 plenary sessions, including 4 keynote talks and 7 panel discussions. More than 400 attendees representing the pharma, biotech, academic, regulatory, and private investment communities gathered to discuss the rapid advancement in scientific, clinical, and business developments in IO, with the goal of accelerating the development of new therapeutics for patients. Over 350 partnering meetings took place over the 3-day conference.“360 degrees means we really want to speak to all stakeholders,” stated Dr. Hoos. The meeting is structured for the scientists to bring their most promising next-generation mechanisms that will help address these challenges. However, it is also important to look at therapies that haven't worked, so we don't repeat the same challenges of the past, he noted. “But IO360° is not just the science, it's about the entire ecosystem in which the science exists, and that includes the patients and those that provide the funding to make the science happen.”Michel Sadelain, MD, PhD, of Memorial Sloan Kettering Cancer Center, opened the meeting with a keynote, Chimeric Antigen Receptor (CAR) - T Cell Therapy and the CD19 Paradigm. With two CD19 CAR-T cells (CAR Ts) approved in 2017, Dr. Sadelain identified three new directions being taken to optimize CAR T therapy and develop next-generation CAR Ts. The first is addressing exhaustion (loss of functionality) using genome engineering at a carefully select locus (TRAC) to create more potent CAR Ts and incorporating new designs that modify the activating portion of the CAR and balance rapid expansion and retained memory (1XX CAR). The second is gaining insight into the pathophysiology of cytokine release syndrome, including CAR T–macrophage interactions, to try and reduce toxicity. The third is employing new strategies for circumventing antigen escape, such as use of radiosensitization and combinatorial targeting.The Discovery and Preclinical Science plenary focused on strategies being investigated to modify the tumor microenvironment and address limitations of patient-sourced therapies. According to the plenary chair, Ronald Herbst, PhD, “we are all excited about the potential for immunotherapy for patients with cancer, but many patients don't respond to checkpoint inhibitors.” Part of the problem is explained by the fact that “immune contexture varies within and across tumor types, and so-called ‘hot’ versus ‘cold’ tumors,” he noted. In order to increase the efficacy of immunotherapy, a number of areas are actively being targeted, including antigen presentation, innate mechanisms of activation, the tumor microenvironment, and overcoming immunosuppression.A variety of cells, growth factors, and cytokines in the tumor microenvironment play a pivotal role in whether or not immunotherapy is effective. Various strategies are being employed that attempt to modify the tumor microenvironment to overcome immunosuppressive mechanisms, such as blocking adenosine with an anti-CD73 monoclonal antibody (oleclumab, Medimmune) or an A2A receptor antagonist (CPI-144, Corvus), or inhibiting the IDO (indoleamine 2,3-dioxygenase) pathway (indoximod, NewLink Genetics). Other strategies are being employed to enhance the efficacy of cytokines to augment the expansion and activation of T cells, such as engineering enhanced versions of growth factors such as interleukin-2 (IL-2; NKTR-214, Nektar, and MDNA109, Medicenna) and IL-10 (pegilodecakin, ARMO). For example, pegilodecakin, a long-acting pegylated form of IL-10, induces hallmarks of CD8+ T cell immunity in cancer patients. According to Aung Naing, MD, and Martin Oft, MD, pegilodecakin demonstrated clinical benefit in studies as a single agent and in combination with both chemotherapy and checkpoint inhibitors across several tumor types. The agent is currently being investigated in a Phase 3 trial in metastatic pancreatic cancer.Off-the-shelf hematopoietic cell products are being developed to address some of the limitations of patient-sourced cell therapies, such as heterogeneity, single-patient manufacturing, need for sufficient cells, extended production time, and cost. For example, engineered CAR natural killer cells, derived from induced pluripotent stem cells, are being developed that incorporate several individual components that together help to enhance persistence and antitumor efficacy (FT596, Fate Therapeutics). Multicombinatorial strategies such as this may be key in reigniting the endogenous immune system and improving efficacy in solid tumor space.Genentech's Priti Hegde, PhD, opened the Translational Science and Emerging Biomarkers plenary, part 1, with a keynote, Biomarker Signaling: Turning Cold Tumors Hot. Individual cancer types can be characterized along the tumor immunity continuum based on immune phenotype (i.e. inflamed or noninflamed) and tumor mutational burden (TMB). How can we generate an immune response signal in noninflamed tumors when most do not achieve the TMB threshold that selects for benefit? Dr. Hedge highlighted two approaches: adaptive immunity, which has the potential to drive memory response, and synthetic immunity, which has the potential to sustain efficacy and drive log kill. An example of an adaptive immunity approach is neoantigen-specific T-cell therapy, in which there are limited but encouraging data demonstrating its ability to promote adaptive immunity in noninflamed tumors. Synthetic immunity approaches include engineered T cells (e.g. NY-ESO SPEAR T cells [GSK/Adaptimmune], BMCA CAR Ts) and bi-specific biologics (e.g. antibodies, BITEs® [Amgen], ImmTAC® [Immunocore]), in which there is a proof of concept that these approaches are feasible in solid tumors and checkpoint inhibitor-refractory hematologic malignancies.One may also need to address the underlying biology to turn cold tumors hot. According to Dr. Hegde, the future of immunotherapy may be highly personalized, and one will need to look at a variety of markers in biopsy specimens using a variety of techniques. This will only be possible if we have: (1) a tissue-conserving, regulatory-grade decentralized platform to be able to run all of these assays in trials and (2) trial designs and statistical analysis plans that enable diagnostic signal-seeking validation and a path for registration.The remainder of the plenary reported on translational data and evolving biomarkers and applications to help support decision-making for IO drug development.Negative results from the Phase 3 study of the therapeutic prostate cancer vaccine PROSTVAC (Bavarian Nordic) show that a combinatorial approach may be needed with vaccines. Similarly, oncolytic viruses may need multiple transgenes and mechanisms to reverse complex immunosuppressive microenvironments. To address this issue, T-Stealth™ oncolytic viruses (BeneVir) can incorporate multiple genes, evade clearance by the innate and adaptive immune systems, and be combined with other drugs and IO agents.With the increasing need for biomarker support, the clinical trial laboratory reality in the IO space is complex. Patrice Hugo, PhD (Q2 Solutions), summarized important features to consider when selecting a lab partner for drug development. Key strategies to successfully introduce innovation in the clinical trial lab space include joint review of pros and cons of technologies, consideration of joint investments, performing Phase 1 specialized testing in niche labs/academic settings with transfer to a central lab, and discussion and planning for regulatory requirements.Advances in positron emission tomography (PET) imaging and radiomics provide a quantitative, noninvasive way to assess the dynamic changes of the immune system. For example, CD8 PET (Imaging Endpoints) may help distinguish between hot and cold tumors and address fundamental questions regarding the role of CD8 cells in the tumor microenvironment.Other unique biomarkers and applications under investigation include MultiOmyx™ (NeoGenomics), a proprietary multi “omic” technology that enables detection and visualization of up to 60 biomarkers on a single slide; immunosequencing (immunoSEQ, Adaptive Biotechnologies), a clinical diagnostic for monitoring clonal expansion and predicting/evaluating response to therapy that can also be used in combination with cellular immunology and computational biology (Multiplexed Identification of T cell Receptor Antigen [MIRA] assay, Adaptive Biotechnologies) to map T-cell receptors; and CANscript™ (Mitra), a personalized ex vivo histoculture approach that can be used to evaluate drug-induced modulation of the tumor microenvironment and predict clinical performance.The IO Novel Technologies and Innovative Solutions plenary showcased companies that have technologies and solutions that will help stakeholders in the IO field advance developments for cancer therapeutics. Presenters included Advaxis, Bioxcel Therapeutics, IAG, Provecs Medical, Rgenix, and Sensei Bio.Andrew Baum, MD (Citi), opened the Financial and Commercial Implications plenary with a keynote, Evaluation and Forecast of the IO Space. He started off by discussing key questions on health-care investors' minds. According to Dr. Baum, “what investors don't like very much about IO is that the technology cycles are short, so you can go from here to zero very quickly very easily.” He cited ipilimumab and the fact that it was quickly eclipsed by anti-PD (L)-1 agents. Another issue is the “paradox of choice,” as there are so many different modalities. “It's almost overwhelming,” he noted, “especially for someone that doesn't have a deep scientific background to interpret a Phase one trial.” Other questions involve primary and secondary resistance, cell therapy manufacturing constraints, minimizing/managing toxicity, and financial toxicity. However, despite these questions, “the good news is the amount of capital, the enthusiasm, and the scientific advancement all mean that we're going to make huge strides in IO, I have no doubt.”Dr. Baum stressed the importance of learning from historic disappointments and noted that we need better biomarkers, better trials, and patience so that the benefits can be extended to more patients. He ended his presentation with a slide showing Citi's top 10 novel IO targets for 2020, in which IL-2/IL-15 took the top spot.Khalil Barrage (Invus) agreed that the IO revolution has led to unprecedented investor enthusiasm for oncology, unlocking massive commercial opportunities. However, the discovery of checkpoints and their curative potential has led to hype in IO drug discovery, resulting in risky behavior. In addition, the flood of capital has lowered potential returns and there are a lot of IO agents in development with poorly validated rationale. As a result, Invus' approach to investing incorporates strategies such as diversification, selectivity, exploring synergistic opportunities, investing where innovation is happening, paying a premium for validated approaches when warranted, and assessing reimbursement.The plenary concluded with a panel discussion on monetizing science: the preparation of an IPO, straight licensing with the transition to a public company, and decision-making on prioritization within portfolios. Key takeaways included strategies for building out scientific and executive talent, the importance of having a scientific advisory board to test out the research, and being prepared to be a public company.The Trends and Collaborations plenary featured presentations by three major industry media companies in the IO field, which discussed new trends and their effect on the investment landscape.BioCentury analyzes IO trends at recent medical meetings using machine learning, began Simone Fishburn, PhD, VP, and Executive Editor. Despite the huge focus on PD (L)-1, academics and companies are aggressively looking for, and finding new targets, with LAG3 topping the list in company oncology pipelines in 2019. CAR T activity is moving into solid tumors, with new constructs and multiple tumor antigens targeted. Immunometabolism and tumor mutation burden are hot topics. Funding for IO start-ups is outstripping other areas, both inside and outside oncology, drawing traditional and corporate investors.According to John D. Carroll (Endpoints News), these trends are supported by global data published by the Cancer Research Institute, which show that there were 3394 IO agents representing 417 targets in the pipeline in 2018, representing a 67% increase over 2017.How are these trends affecting the investment landscape? According to Jeff Bockman, PhD (Cello Health BioConsulting), IO dominates oncology growth, but not sales. Moreover, although IO deals have shown evidence of slowing, whether due to maturation, saturation, or fatigue, and oncology and IO investments remain robust.The Business Development plenary, hosted by Solebury Trout, included panel discussions on partnering, fundraising, and rational investing. The first panel discussed IO partnering strategies from the viewpoint of pharma and academia. According to Dr. Hoos, who the partnering in this space have but there has much and is only that companies have started their unique which will a partnering the for is tumor and the and the companies on the panel and there to be both and with some moving from and on those that can IO and agents are being by most in the and are to play which was for and discussed in the IO space and a number of For example, the panel stressed the importance of at and and on key and as a private on their ecosystem their investors with in the past, key to their than at with the top at the with key the of and companies introduce than need to so that can panel focused on IO investment investors this an time, with a future for many modalities. However, the massive of data is it to to to from a The investors on the panel on a variety of such as the of and whether the data support a or whether an agent has a or has a niche in the IO important is a in their and their to plenary ended with a with of by Solebury Trout, the discussion focused on in the company, with a an For companies looking for highlighted the fact that as a and stressed the need to and where are are some very so both and in to a with a can try and to more like in As industry are companies can be quickly with limited capital, like companies have in the began with a keynote, to led by and MD, of of According to Dr. we are at an in it has from one to has the and of tumor types, agents and trials are and there is an to use to enable to of trials are the way new therapies are developed for cancer, make better and more personalized The of are testing drugs where most (i.e. the order of therapy to about response in the of building an to evaluate drugs and using imaging and biomarker and being by is a platform trial for of biopsy is used to assess and imaging and adaptive The and the are structured to enable and release of agents the The primary is response which is a highly of and and is in biomarker The from biomarker and is to drug to Dr. we want innovation to we have to The focus of new drug development be a a from of metastatic to is a huge is also a huge goal of is to of patients to with and of therapy based on Dr. ended with one of for drug from finding out which drug be to the with two The first Science and Emerging Biomarkers Part was led by PhD, of and to focus on biology and to help predict to Technologies discussed included to enhance antibody therapeutics mechanisms of to immune the for biomarker discovery a and a receptor in second for IO was led by of and was for clinical trial who to it to an IO clinical discussed included an clinical trial study a complex Phase 1 trial in IO and clinical trial for The ended in a panel discussion on the challenges with IO data and to advance to PhD, at the and (i.e. may not the clinical benefit of IO agents. As a result, trends include the use of immune response machine learning to the of imaging and new techniques. The IO plenary up the with a discussion of novel imaging are unique challenges with the use of response at IO clinical as a of complex According to some of these challenges can be by the and of response and including a of in the can be by the use of and and analysis and PhD are being used in with to more from to as as better between and such as the CD8 PET discussed is also an evolving Similarly, imaging using PET an to assess all of a tumors for with a single PET and assess use of a novel three opened with the of with cancer, cancer 10 as metastatic chemotherapy and therapies, and of an immunotherapy trial at the The the that cancer, and those cells in the an of the cells and the cancer has the of being the first to be of metastatic cancer a of to to from in the concluded with some to patients who be in the same the same to with cancer or out as much as you can about to a cancer to to not just one of therapy but several of out about clinical trials and whether you can in The is out there and you as try and on the was a panel discussion on to IO in a The are to but be and and the of a tumor to be want to if the tumor has by the adaptive immune is it by T cells if do have an immunosuppressive factors are in the tumor However, are an important the is the of the cell types are but also and able to look in the is but it doesn't provide all the can all these be with a new plenary for Cell According to Dr. Gulley, therapy has the to on the of cancer there is activity in hematologic but it's is needed to achieve the same effect in solid tumors, so this is where there is much The is to was in studies but the benefit to a of patients. The new technologies and targets discussed in this plenary to do just technology to a T cells their However, in the of approved CAR are According to MD of this as a of of and of He cited a where CD19 in a single cell led to by the CD19 which may have important for manufacturing and other cell therapies. For and the can be with a CAR T or it can be with a new of CAR that the SPEAR are an engineered T-cell of cells that are to a that a antigen in many technology an over CAR T therapy in that it to both and results have in a cancer for which there are no therapies the of noted products a number of over CAR Ts. CAR Ts Chimeric Antigen Receptor developed using the platform are being investigated in and multiple The is to multiple to create T cells with such as the ability to or overcome may an over other therapies in solid tumors in that multiple tumor antigens and there is a of or The technology used to develop the that has and of efficacy have in and the for the has from to to and the is a therapies have the potential to enhance CAR T activity in solid tumors. combination strategies consider both and can be used to enhance cell and and factors in the tumor microenvironment, or and plenary ended with a panel discussion on and clinical to IO therapeutics that will to more and therapies. of the strategies discussed were including a to and products and addressing antigen with or combination In order to we need to address like the when moving from in to the clinical as as cell and the used to create the may the cells, manufacturing and we need to cell therapies so that more patients will have conference concluded with the IO Development plenary, which discussed recent IO clinical The plenary began with an of data for the activity has demonstrated in more than cancer types. The agent has across more than including in is moving into the of therapy, and next-generation biomarkers are to help promising were also for a a and combination immunotherapy and the tumor receptor has to more benefit in Dr. Hoos. However, there is a lot of As a result, “we need to new to the benefit PD Cell therapy has really to the of engineered and we are to the benefit from to solid tumors and overcoming the such as T-cell that in the for patients is
With the rapid development of medical information services, the construction of intelligent hospitals is opening up a new mode of medical treatment in the health care industry. Medical data is gradually becoming more and more important, while it also faces some challenges, among which the most urgent problem to be solved is data security and privacy protection. In the construction of intelligent hospitals, the safety issues among the basic information of patients, the protection of medical information and inter-institutional information sharing have become the focus at this stage. Blockchain technology, with highly security, reliable architecture and algorithm design have operated stably in the financial industry for more than seven years. The related innovative technologies such as distributed ledgers, smart contracts, symmetric encryptions and consensus mechanisms are used widely in many fields. This paper will take the demonstration construction of Chongqing Intelligent Hospital as an example, which tries to combine the blockchain, homomorphic encryption and zero-knowledge proof technology to carry out the research on the security construction and data privacy protection of intelligent hospitals.
Open access
Privacy-Preserving Technologies in Data
Blockchain Technology Applications and Security
Artificial Intelligence in Healthcare and Education
Amar Rasheed, Ray R. Hashemi, Ayman Bagabas, Jeffrey A. Young · 6 authors
The Internet of Things (IoT) has revolutionized the way of how pervasive computing devices communicate and disseminate information over the global network. A plethora of user data is collected and logged daily into cloud-based servers. Such data can be analyzed by the IoT infrastructure to capture users' behaviors (e.g. users' location, tagging of smart home occupancy). This brings a new set of security challenges, specifically user anonymity. Existing access control and authentication technologies failed to support user anonymity. They relied on the surrendering of the device/user authentication parameters to the trusted server, which hence could be utilized by the IoT infrastructure to track users' behavioral patterns. This paper, presents two novel configurable privacy-preserving authentication schemes. User anonymity capabilities were incorporated into our proposed authentication schemes through the implementation of two crypto-based approaches (i) Zero Knowledge Proof (ZKP) and (ii) Verifiable Common Secret Encoding (VCSE). We consider a user-oriented approach when determining user anonymity. The proposed authentication schemes are dynamically capable of supporting various levels of user privacy based on the user preferences. To validate the two schemes, they were fully implemented and deployed on an IoT testbed. We have tested the performance of each proposed schemes in terms of power consumption and computation time. Based on our performance evaluation results, the proposed ZKP-based approach provides better performance compared to the VCSE-based approach.
Blockchain is the core technology underlying the first decentralized cryptocurrency, Bitcoin, introduced by Nakamoto in 2008. Since then, blockchain technology has many more advancements that are being developed and experimented. In particular, recent blockchain platforms such as Ethereum offer general and executable scripts, namely smart contracts, that can be employed to develop decentralized applications (DApps) in many domains beyond payment. However, the transparency of blockchain data raises concerns for many applications that require high privacy level. Therefore, many privacy enhancing technologies have been applied to DApp development, including zero knowledge proof (ZKP). This paper focuses on a particular kind of ZKP, called zero knowledge range proof (ZKRP), that has been applied in blockchain-based payments for banks. ZKRP allows a user to convince other people that a secret value actually lies within an interval without revealing any information about the secret. Here we introduce a new ZKRP which has the following remarkable features: (1) Non-interactive: No communication is required between a user and a verifier during the proof. (2) Range-flexibility: There is no limitation on the lower bound and the upper bound of the range except that they are natural numbers. (3) Efficiency: Our scheme is modified from that of Pang et al. (2010), yet achieves better security and is more efficient than their scheme. We believe our new ZKRP can be beneficial to the development of DApps and can extend the application scope to more scenarios.
Blockchain Technology Applications and Security
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
Authentication is the act of confirming the validity of someone’s personal data. In the traditional authentication system, username and password are sent to the server for verification. However, this scheme is not secure, because the password can be sniffed. In addition, the server will keep the user’s password for the authentication. This makes the system vulnerable when the database server is hacked. Zero knowledge authentication allows server to authenticate user without knowing the user’s password. In this research, this scheme was implemented with Guillou-Quisquater protocol. Two login mechanisms were used: file-based certificate with key and local storage. Testing phase was carried out based on the Open Web Application Security Project (OWASP) penetration testing scheme. Furthermore, penetration testing was also performed by an expert based on Acunetix report. Three potential vulnerabilities were found and risk estimation was calculated. According to OWASP risk rating, these vulnerabilities were at the medium level.
Reto E. Koenig, Lukas Laederach, Cédric von Allmen
This paper describes a new but state-of-the-art approach to provide authenticity in mqtt sessions using the means of zero-knowledge-proofs. This approach completely voids session hijacking for the mqtt protocol and provides authenticity without the need for any network-security nor channel-security nor broker-based predefined ACLs. The presented approach does not require the broker to keep any secrets for session handling, what so ever. Moreover, it allows the clientID, which represents the identification for a session, to be publicly known. The presented approach allows completely anonymous but authentic sessions, hence the broker does not need any a priori knowledge of the client-party. As it is especially targeted for applications within the world of IoT, the presented approach is tuned to require only the minimum in extra power in terms of energy and space. The approach does not introduce any new concept, but simply fusions a state-of-the-art cryptographic zero knowledge proof of identity with the existing MQTT-5 specification. Thus no protocol extension is required in order to provide the targeted security properties. The described approach is completely agnostic to the application layer at the client side and is only required during mqtt-session establishment.
Eli Ben‐Sasson, Lior Goldberg, Swastik Kopparty, Shubhangi Saraf
Motivated by the quest for scalable and succinct zero knowledge arguments, we revisit worst-case-to-average-case reductions for linear spaces, raised by [Rothblum, Vadhan, Wigderson, STOC 2013]. The previous state of the art by [Ben-Sasson, Kopparty, Saraf, CCC 2018] showed that if some member of an affine space U is δ-far in relative Hamming distance from a linear code V - this is the worst-case assumption - then most elements of U are almost-δ-far from V - this is the average case. However, this result was known to hold only below the "double Johnson" function of the relative distance δ_V of the code V, i.e., only when δ < 1-(1-δ_V)^(1/4). First, we increase the soundness-bound to the "one-and-a-half Johnson" function of δ_V and show that the average distance of U from V is nearly δ for any worst-case distance δ smaller than 1-(1-δ_V)^(1/3). This bound is tight, which is somewhat surprising because the one-and-a-half Johnson function is unfamiliar in the literature on error correcting codes. To improve soundness further for Reed Solomon codes we sample outside the box. We suggest a new protocol in which the verifier samples a single point z outside the box D on which codewords are evaluated, and asks the prover for the value at z of the interpolating polynomial of a random element of U. Intuitively, the answer provided by the prover "forces" it to choose one codeword from a list of "pretenders" that are close to U. We call this technique Domain Extending for Eliminating Pretenders (DEEP). The DEEP method improves the soundness of the worst-case-to-average-case reduction for RS codes up their list decoding radius. This radius is bounded from below by the Johnson bound, implying average distance is approximately δ for all δ < 1-(1-δ_V)^(1/2). Under a plausible conjecture about the list decoding radius of Reed-Solomon codes, average distance from V is approximately δ for all δ. The DEEP technique can be generalized to all linear codes, giving improved reductions for capacity-achieving list-decodable codes. Finally, we use the DEEP technique to devise two new protocols: - An Interactive Oracle Proof of Proximity (IOPP) for RS codes, called DEEP-FRI. The soundness of the protocol improves upon that of the FRI protocol of [Ben-Sasson et al., ICALP 2018] while retaining linear arithmetic proving complexity and logarithmic verifier arithmetic complexity. - An Interactive Oracle Proof (IOP) for the Algebraic Linking IOP (ALI) protocol used to construct zero knowledge scalable transparent arguments of knowledge (ZK-STARKs) in [Ben-Sasson et al., eprint 2018]. The new protocol, called DEEP-ALI, improves soundness of this crucial step from a small constant < 1/8 to a constant arbitrarily close to 1.
Blockchain offers an innovative approach to storing information, executing transactions, performing functions, and establishing trust in an open environment. Many consider blockchain as a technology breakthrough for cryptography and cybersecurity, with use cases ranging from globally deployed cryptocurrency systems like Bitcoin, to smart contracts, smart grids over the Internet of Things, and so forth. Although blockchain has received growing interests in both academia and industry in the recent years, the security and privacy of blockchains continue to be at the center of the debate when deploying blockchain in different applications. This article presents a comprehensive overview of the security and privacy of blockchain. To facilitate the discussion, we first introduce the notion of blockchains and its utility in the context of Bitcoin-like online transactions. Then, we describe the basic security properties that are supported as the essential requirements and building blocks for Bitcoin-like cryptocurrency systems, followed by presenting the additional security and privacy properties that are desired in many blockchain applications. Finally, we review the security and privacy techniques for achieving these security properties in blockchain-based systems, including representative consensus algorithms, hash chained storage, mixing protocols, anonymous signatures, non-interactive zero-knowledge proof, and so forth. We conjecture that this survey can help readers to gain an in-depth understanding of the security and privacy of blockchain with respect to concept, attributes, techniques, and systems.
Vehicular Ad Hoc Networks (VANETs) are a particular subclass of mobile ad hoc networks that raise a number of security challenges, notably from the way users authenticate the network. Authentication technologies based on existing security policies and access control rules in such networks assume full trust on Roadside Unit (RSU) and authentication servers. The disclosure of authentication parameters enables user's trace-ability over the network. VANETs' trusted entities (e.g. RSU) can utilize such information to track a user traveling behavior, violating user privacy and anonymity. In this paper, we proposed a novel, light-weight, Adaptive Group-based Zero Knowledge Proof-Authentication Protocol (AGZKP-AP) for VANETs. The proposed authentication protocol is capable of offering various levels of users' privacy settings based on the type of services available on such networks. Our scheme is based on the Zero-Knowledge-Proof (ZKP) crypto approach with the support of trade-off options. Users have the option to make critical decisions on the level of privacy and the amount of resources usage they prefer such as short system response time versus the number of private information disclosures. Furthermore, AGZKP-AP is incorporated with a distributed privilege control and revoking mechanism that render user's private information to law enforcement in case of a traffic violation.
Lake Bu, Rashmi Agrawal, Hai Cheng, Michel A. Kinsy
The development and implementation of post-quantum cryptosystems have become a pressing issue in the design of secure computing systems, as general quantum computers have become more feasible in the last two years. In this work, we introduce a set of hardware post-quantum cryptographic primitives (PCPs) consisting of four frequently used security components, i.e., public-key cryptosystem (PKC), key exchange (KEX), oblivious transfer (OT), and zero-knowledge proof (ZKP). In addition, we design a high speed polynomial multiplier to accelerate these primitives. These primitives will aid researchers and designers in constructing quantum-proof secure computing systems in the post-quantum era.