Lightweight symmetric cryptography

The Internet of Things is one of the principal trends in information technology nowadays. The main idea behind this concept is that devices communicate autonomously with each other over the Internet. Some of these devices have extremely limited resources, such as power and energy, available time for computations, amount of silicon to produce the chip, computational power, etc. Classical cryptographic primitives are often infeasible for such constrained devices. The goal of lightweight cryptography is to introduce cryptographic solutions with reduced resource consumption, but with a sufficient security level. Although this research area was of great interest to academia during the last years and a large number of proposals for lightweight cryptographic primitives have been introduced, almost none of them are used in real-word. Probably one of the reasons is that, for academia, lightweight usually meant to design cryptographic primitives such that they require minimal resources among all existing solutions. This exciting research problem became an important driver which allowed the academic community to better understand many cryptographic design concepts and to develop new attacks. However, this criterion does not seem to be the most important one for industry, where lightweight may be considered as "rightweight". In other words, a given cryptographic solution just has to fit the constraints of the specific use cases rather than to be the smallest. Unfortunately, academic researchers tended to neglect vital properties of the particular types of devices, into which they intended to apply their primitives. That is, often solutions were proposed where the usage of some resources was reduced to a minimum. However, this was achieved by introducing new costs which were not appropriately taken into account or in such a way that the reduction of costs also led to a decrease in the security level. Hence, there is a clear gap between academia and industry in understanding what lightweight cryptography is. In this work, we are trying to fill some of these gaps. We carefully investigate a broad number of existing lightweight cryptographic primitives proposed by academia including authentication protocols, stream ciphers, and block ciphers and evaluate their applicability for real-world scenarios. We then look at how individual components of design of the primitives influence their cost and summarize the steps to be taken into account when designing primitives for concrete cost optimization, more precisely - for low energy consumption. Next, we propose new implementation techniques for existing designs making them more efficient or smaller in hardware without the necessity to pay any additional costs. After that, we introduce a new stream cipher design philosophy which enables secure stream ciphers with smaller area size than ever before and, at the same time, considerably higher throughput compared to any other encryption schemes of similar hardware cost. To demonstrate the feasibility of our findings we propose two ciphers with the smallest area size so far, namely Sprout and Plantlet, and the most energy efficient encryption scheme called Trivium-2. Finally, this thesis solves a concrete industrial problem. Based on standardized cryptographic solutions, we design an end-to-end data-protection scheme for low power networks. This scheme was deployed on the water distribution network in the City of Antibes, France

Flush communication channels: Effective implementation and verification

Flush communication channels, or F-channels, generalize more conventional asynchronous communication paradigms. A distributed system which uses an F-channel allows a programmer to define the delivery order of each message in relation to other messages transmitted on the channel. Unreliable datagrams and FIFO (first-in-first-out) communication channels have strictly defined delivery semantics. No restrictions are allowed on message delivery order with unreliable datagrams--message delivery is completely unordered. FIFO channels, on the other hand, insist messages are delivered in the order of their transmission. Flush channels can provide either of these delivery order semantics; in addition, F-channels allow the user to define the delivery of a message to be after the delivery of all messages previously transmitted or before the delivery of all messages subsequently transmitted or both. A system which communicates with a flush channel has a message delivery order that is a partial order.;Dynamically specifying a partial message delivery order complicates many aspects of how we implement and reason about the communication channel. From the system\u27s perspective, we develop a feasible implementation protocol and prove its correctness. The protocol effectively handles the partially ordered message delivery. From the user\u27s perspective, we derive an axiomatic verification methodology for flush applications. The added flexibility of defining the delivery order dynamically slightly increases the complexity for the application programmer. Our verification work helps the user effectively deal with the partially ordered message delivery in flush communication

Corporate Social and Environmental Responsibility (CSER) Reporting Practices in a Developing Country: Evidence from Bangladesh

This study explores CSER reporting phenomenon in Bangladesh. Constructivist ontology and interpretivist epistemology research methodology was used. Findings from this engagement-based study reveal the underpinning assumptions of CSER regarding enablers and barriers, stakeholders’ expectations and suggested strategies. Findings and the social system-based theories resonate well with the literature providing theoretical and practical contributions to the body of knowledge. This study provides valuable insights for scholars, policy makers, managers and organisations

The Influence of Bank-Based and Capital Market-Based Impact Investments on SME Financing in Ghana: Governance, Strategy Change and Impacts

Impact investing, defined as direct investments into funds, small and medium-sized enterprises (SMEs) and viable non-profit social enterprises with intentionality to simultaneously realise social impact and financial returns is increasingly attracting the attention of academics and industry practitioners. A contentious claim is that impact investment, as transformational in its approach to entrepreneurial financing, is a panacea to SME financing constraints and solutions to intractable societal problems, is contestable considering the myriad of developmental challenges in Bottom-of-the-Pyramid (BoP) communities in the developing world. Based on an empirical investigation of the influences of finance first and impact first investments into bank-based and capital market-based funds on SMEs in Ghana, this thesis interrogates this claim. Specifically, the thesis argues that though impact investing represents an innovation in private sector approaches to development, the extent to which it can achieve the much-hyped societal transformation in BoP communities cannot be substantiated. This research contributes to the above debate by critically investigating the influences of impact investment funds on investee SMEs through an integrated theoretical framework. The framework draws on the literature from different disciplines including impact investing, social entrepreneurship, strategic management, financial intermediation, economics, SME management and concepts of governance, strategy change and impacts, which was then applied within the research setting of Ghana. Empirically, the thesis develops two case studies of bank-based and capital market-based funds into SMEs, respectively. Qualitative research was employed with data collection comprising in-depth interviews, rapid participant observation complemented by documentary evidence. Findings reveal that the distinctiveness of finance and impact first investors reflect their choices of bank and capital market-based intermediary used resulting in pluralistic, entrepreneurial financing options for categories of SMEs targeted for social impact and financial returns. These findings have implication for fund managers, SME owner-managers and policymakers due to private sector-driven developmental model by impact investors

FGK stars and T Tauri stars: Monograph series on nonthermal phenomena in stellar atmospheres

The purpose of this book, FGK Stars and T Tauri Stars, like all other volumes of this series, is to exhibit and describe the best space data and ground based data currently available, and also to describe and critically evaluate the status of current theoretical models and physical mechanisms that have been proposed to interpret these data. The method for obtaining this book was to collect manuscripts from competent volunteer authors, and then to collate and edit these contributions to form a well structured book, which will be distributed to an international community of research astronomers by NASA and by the French CNRS

Construction management abstracts : cumulative abstracts and indexes of journals in construction management, 1983-2000

The purpose of this document is to provide a single source of reference for every paper published in the journals directly related to research in Construction Management. It is indexed by author and keyword and contains the titles, authors, abstracts and keywords of every article from the following journals: • Building Research and Information (BRI) • Construction Management and Economics (CME) • Engineering, Construction and Architectural Management (ECAM) • Journal of Construction Procurement (JCP) • Journal of Construction Research (JCR) • Journal of Financial Management in Property and Construction (JFM) • RICS Research Papers (RICS) The index entries give short forms of the bibliographical citations, rather than page numbers, to enable annual updates to the abstracts. Each annual update will carry cumulative indexes, so that only one index needs to be consulted

Exploiting user signals and stochastic models to improve information retrieval systems and evaluation

The leitmotiv throughout this thesis is represented by IR evaluation. We discuss different issues related to effectiveness measures and novel solutions that we propose to address these challenges. We start by providing a formal definition of utility-oriented measurement of retrieval effectiveness, based on the representational theory of measurement. The proposed theoretical framework contributes to a better understanding of the problem complexities, separating those due to the inherent problems in comparing systems, from those due to the expected numerical properties of measures. We then propose AWARE, a probabilistic framework for dealing with the noise and inconsistencies introduced when relevance labels are gathered with multiple crowd assessors. By modeling relevance judgements and crowd assessors as sources of uncertainty, we directly combine the performance measures computed on the ground-truth generated by each crowd assessor, instead of adopting a classification technique to merge the labels at pool level. Finally, we investigate evaluation measures able to account for user signals. We propose a new user model based on Markov chains, that allows the user to scan the result list with many degrees of freedom. We exploit this Markovian model in order to inject user models into precision, defining a new family of evaluation measures, and we embed this model as objective function of an LtR algorithm to improve system performances

Advances in Computational Social Science and Social Simulation

Aquesta conferència és la celebració conjunta de la "10th Artificial Economics Conference AE", la "10th Conference of the European Social Simulation Association ESSA" i la "1st Simulating the Past to Understand Human History SPUHH".Conferència organitzada pel Laboratory for Socio­-Historical Dynamics Simulation (LSDS-­UAB) de la Universitat Autònoma de Barcelona.Readers will find results of recent research on computational social science and social simulation economics, management, sociology,and history written by leading experts in the field. SOCIAL SIMULATION (former ESSA) conferences constitute annual events which serve as an international platform for the exchange of ideas and discussion of cutting edge research in the field of social simulations, both from the theoretical as well as applied perspective, and the 2014 edition benefits from the cross-fertilization of three different research communities into one single event. The volume consists of 122 articles, corresponding to most of the contributions to the conferences, in three different formats: short abstracts (presentation of work-in-progress research), posters (presentation of models and results), and full papers (presentation of social simulation research including results and discussion). The compilation is completed with indexing lists to help finding articles by title, author and thematic content. We are convinced that this book will serve interested readers as a useful compendium which presents in a nutshell the most recent advances at the frontiers of computational social sciences and social simulation researc

Federal Register

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii