A P2P Optimistic Fair Exchange (OFE) Scheme For Personal Health Records Using Blockchain Technology

In today’s digital world, it is common to exchange sensitive data between different parties. There are many examples of sensitive data or documents that require a digital exchange, such as banking information, insurance data, health records. In many cases, the exchange exists between unknown and untrusted parties. Therefore, it is essential to execute the data exchange over a fair non-repudiation protocol. In digital communication, non-repudiation is undeniable evidence of one’s responsibility regarding the validity of any data he shares/receives. Usually, this is achieved by the use of a cryptographic digital signature. In this case, the parties cannot deny the authenticity of their digital signature. The protocol satisfies the fairness property if and only if it does not give the sender any advantages over the receiver or vice versa, at any step during the exchange process. Combining fair exchange and non-repudiation for digital exchange is critical in many applications and can be acquired with or without the involvement of any trusted third party (TTP). However, without the involvement of TTP, fairness becomes probabilistic, and the involvement of TTP can cause significant dependency on the third party. Therefore, a peer-to-peer (P2P) (aka offline) fair non-repudiation protocol that does not require a trusted third-party is desirable in many applications. Blockchain is designed in such a way that the network can handle the trustless environment and deliver the correct result. Thus, if the exchanges are done leveraging Blockchain, it will ensure true fairness, and at the same time, none of the participants have to deal with the trust issue. In this thesis we propose a P2P fair non-repudiation data exchange scheme by leveraging Blockchain and distributed ledger technology. The scheme combines on-chain and off-chain communication patterns to enable the exchange of personal health records between patients and healthcare providers. We provide an informal reasoning of the proposed scheme. Moreover, we propose a design and implementation agnostic to existing Blockchain platforms to enable unbiased evaluation of the proposed scheme. Finally, we make a comparative analysis of the result derived from our approach with the existing one

On Structure-Preserving Cryptography and Lattices

The Groth-Sahai proof system is a highly efficient pairing-based proof system for a specific class of group-based languages. Cryptographic primitives that are compatible with these languages (such that we can express, e.g., that a ciphertext contains a valid signature for a given message) are called structure-preserving . The combination of structure-preserving primitives with Groth-Sahai proofs allows to prove complex statements that involve encryptions and signatures, and has proved useful in a variety of applications. However, so far, the concept of structure-preserving cryptography has been confined to the pairing setting. In this work, we propose the first framework for structure-preserving cryptography in the lattice setting. Concretely, we - define structure-preserving sets as an abstraction of (typically noisy) lattice-based languages, - formalize a notion of generalized structure-preserving encryption and signature schemes capturing a number of existing lattice-based encryption and signature schemes), - construct a compatible zero-knowledge argument system that allows to argue about lattice-based structure-preserving primitives, - offer a lattice-based construction of verifiably encrypted signatures in our framework. Along the way, we also discover a new and efficient strongly secure lattice-based signature scheme. This scheme combines Rückert\u27s lattice-based signature scheme with the lattice delegation strategy of Agrawal et al., which yields more compact and efficient signatures. We hope that our framework provides a first step towards a modular and versatile treatment of cryptographic primitives in the lattice setting

Borderline Justice

Borderline Justice describes the exclusionary policies, inhumane decisions and obstacles to justice for refugees and migrants in the British legal system. Frances Webber, a long-standing legal practitioner, reveals how the law has been (mis)applied to migrants, refugees and other ‘unpopular minorities’. This book records some of the key legal struggles of the past thirty years which have sought to preserve values of universality in human rights - and the importance of continuing to fight for those values, inside and outside the courtroom. The themes and analysis cross boundaries of law, politics, sociology, criminology, refugee studies and terrorism studies, appealing to the radical tradition in all these disciplines

Borderline Justice

Borderline Justice describes the exclusionary policies, inhumane decisions and obstacles to justice for refugees and migrants in the British legal system. Frances Webber, a long-standing legal practitioner, reveals how the law has been (mis)applied to migrants, refugees and other ‘unpopular minorities’. This book records some of the key legal struggles of the past thirty years which have sought to preserve values of universality in human rights - and the importance of continuing to fight for those values, inside and outside the courtroom. The themes and analysis cross boundaries of law, politics, sociology, criminology, refugee studies and terrorism studies, appealing to the radical tradition in all these disciplines

Middleware support for non-repudiable business-to-business interactions

The wide variety of services and resources available over the Internet presents new opportunities for organisations to collaborate to reach common goals. For example, business partners wish to access each other’s services and share information along the supply chain in order to compete more successfully in the delivery of goods or services to the ultimate customer. This can lead to the investment of significant resources by business partners in the resulting collaboration. In the context of such high value business-to-business (B2B) interactions it is desirable to regulate (monitor and control) the behaviour of business partners to ensure that they comply with agreements that govern their interactions. Achieving this regulation is challenging because, while wishing to collaborate, organisations remain autonomous and may not unguardedly trust each other. Two aspects must be addressed: (i) the need for high-level mechanisms to encode agreements (contracts) between the interacting parties such that they can be used for run-time monitoring and enforcement, and (ii) systematic support to monitor a given interaction for conformance with contract and to ensure accountability. This dissertation concerns the latter aspect — the definition, design and implementation of underlying middleware support for the regulation of B2B interactions. To this end, two non-repudiation services are identified — non-repudiable service invocation and non-repudiable information sharing. A flexible nonrepudiation protocol execution framework supports the delivery of the identified services. It is shown how the services can be used to regulate B2B interactions. The non-repudiation services provide for the accountability of the actions of participants; including the acknowledgement of actions, their run-time validation with respect to application-level constraints and logging for audit. The framework is realised in the context of interactions with and between components of a J2EE application server platform. However, the design is sufficiently flexible to apply to other common middleware platforms.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The compatibility of dispute resolution mechanisms with national culture in the construction industry : a case study of the Malaysian statutory adjudication regime

In 2012, Malaysia became one of the many countries worldwide to introduce statutory adjudication into its construction industry. As with other countries, the purpose of the legislation – contained in the Construction Industry Payment and Adjudication Act 2012 (CIPAA), was to ensure that construction payment disputes were resolved in an efficient and timely manner, thereby easing the problem of cash flow within the industry. Until that time - with the single exception of Singapore, with its unique history and commercial status within the region, no other Asian country had taken this step. Essentially statutory adjudication was being entirely confined to the construction industries of the Western, English-speaking world.The introduction of statutory adjudication - an adversarial form of dispute resolution, in Malaysia that is associated with very different traditions of cultural interaction, therefore raises a potential question of cultural incompatibility between the method of dispute resolution and the national culture of the society in which it is implemented. National culture refers to a set of beliefs, values, norms, and behaviour shared collectively by the population of a nation. Historically, it has played a significant role in shaping approaches to dispute resolution in national settings.The purpose of this research is therefore to assess the compatibility of an adversarial method of dispute resolution with national culture in the construction industry of the Malaysian society. It takes the recent introduction of adjudication in Malaysia as a single qualitative case study of this wider phenomenon. The research establishes a set of propositions based on the pattern of Malaysia’s national culture in four distinctive dimensions derived from Hofstede’s national culture model - namely individualism/collectivism, masculinity/femininity, power distance and uncertainty avoidance. The research utilises the four propositions by conceptually relating each of the dimensions to the key principles of dispute resolution process. The research draws data by 15 semi-structured interviews from various key stakeholders within the Malaysian construction industry. Through thematic analysis, data were coded and categorized to support the inquiry. Patterns emerging from the data were then compared against each of the propositions. Findings of the study suggest that adjudication is appropriate and fitting to the national culture of the Malaysian construction industry, thus invalidating initial assumptions about its incompatibility with Malaysian national culture.The research contributes to knowledge by presenting an in-depth case study of a single adversarial dispute resolution mechanism in a single Malaysia to understand how cultural values can influence the process of resolving construction industry disputes through the lens of national culture. Its findings also foster a better understanding of national culture amongst policy makers when preparing to implement internationally-inspired legislative changes in local settings