AN ARCHITECTURAL APPROACH FOR REDUCINGPOWER AND INCREASING SECURITY OF RFID TAGS

Radio Frequency Identification (RFID) technology is currently employed for a variety of applications such as RFID-based wireless payment, healthcare, homeland security, asset management,etc. Due to newer privacy requirements and increasingly secure applications, typical RFID tags are required to expand security features such as data encryption and safe transactions. However, RFID tags have extremely strict low-power consumption requirements. Thus, reduced power consumption and secure data transactions are two main problems for the next generation RFID tags.This dissertation presents an architectural approach to address these two main problems.This dissertation provides a multi-domain solution to improve the power consumption andsecurity, while also reducing design time and verification time of the system. In particular, Idescribe (1)a smart buffering technique to allow a tag to remain in a standby mode until addressed,(2)a multi-layer, low-power technique that transcends the passive-transaction, physical, and data layers to provide secure transactions, (3) an FPGA-based traffic profiler system to generate traces of RFID communications for both tag verification and power analysis without the need of actual hardware, and (4) a design automation technique to create physical layer encoding and decoding blocks in hardware suitable for RFID tags.This dissertation presents four contributions: (1) As a result, based on a Markov Process energymodel, the smart buffering technique is shown to reduce power consumption by 85% over a traditionalactive tag; (2) The multi-layer, low-power security technique provides protection againstmalicious reader attacks to disable the tag, to steal the information stored in or communicatedto the device. The power consumption overhead for implementing these layers of security is increased approximately 13% over the basic tag controller; (3) In addition, the FPGA-based traffic profiler system has been able to generate traces for ISO 18000 part 6C (EPC Gen2) protocol; and (4) The designs of endocing/decoding blocks are generated automatically by the Physical LayerSynthesis tool for five protocols used in or related to RFID. Consequently, any power consumption of five designs is less than 5 £gW. Furthermore, compared with five designs implemented by hand, the difference of the power consumption between two of them is less than 7% at most

A proof-of-proximity framework for device pairing in ubiquitous computing environments

Ad hoc interactions between devices over wireless networks in ubiquitous computing environments present a security problem: the generation of shared secrets to initialize secure communication over a medium that is inherently vulnerable to various attacks. However, these ad hoc scenarios also offer the potential for physical security of spaces and the use of protocols in which users must visibly demonstrate their presence and/or involvement to generate an association. As a consequence, recently secure device pairing has had significant attention from a wide community of academic as well as industrial researchers and a plethora of schemes and protocols have been proposed, which use various forms of out-of-band exchange to form an association between two unassociated devices. These protocols and schemes have different strengths and weaknesses – often in hardware requirements, strength against various attacks or usability in particular scenarios. From ordinary user‟s point of view, the problem then becomes which to choose or which is the best possible scheme in a particular scenario. We advocate that in a world of modern heterogeneous devices and requirements, there is a need for mechanisms that allow automated selection of the best protocols without requiring the user to have an in-depth knowledge of the minutiae of the underlying technologies. Towards this, the main argument forming the basis of this dissertation is that the integration of a discovery mechanism and several pairing schemes into a single system is more efficient from a usability point of view as well as security point of view in terms of dynamic choice of pairing schemes. In pursuit of this, we have proposed a generic system for secure device pairing by demonstration of physical proximity. Our main contribution is the design and prototype implementation of Proof-of-Proximity framework along with a novel Co- Location protocol. Other contributions include a detailed analysis of existing device pairing schemes, a simple device discovery mechanism, a protocol selection mechanism that is used to find out the best possible scheme to demonstrate the physical proximity of the devices according to the scenario, and a usability study of eight pairing schemes and the proposed system

Perception and performance: an evaluation of multimodal feedback for the assessment of curve shape differences

The EU-funded SATIN project sought to provide a multimodal interface to aid product designers in judging the quality of curved shapes. This thesis outlines a research programme designed to assist in the exploration of fundamental issues related to this project, and provide a means to evaluate the success of such interfaces more generally. Therefore, three studies were undertaken with the aim of exploring the value of haptic and sound feedback in the perception of curve shape differences, and through the knowledge gained provide an evaluative framework for the assessment of such interfaces. The first study found that visual, haptic, and visual-haptic perception was insufficient to judge discontinuities in curvature without some further augmentation. This led to a second study which explored the use of sound for conveying curve shape information. It was found that sine waves or harmonic sounds were most suited to for this task. The third study combined visual-haptic and auditory information. It was found that sound improved the perception of curve shape differences, although this was dependent upon the type of sonification method used. Further to this, data from studies one and three were used to identify gradient as the active mechanism of curve shape differentiation and provided a model for the prediction of these differences. Similarly performance data (response time, accuracy, and confidence) were analysed to produce a model for the prediction of user performance at varying degrees of task difficulty. The research undertaken across these studies was used to develop a framework to evaluate multimodal interfaces for curve shape exploration. In particular a ‘discount’ psychophysical method was proposed, along with predictive tools for the creation of perceptual and performance metrics, plus guidelines to aid development. This research has added to fundamental knowledge and provided a useful framework through which future multimodal interfaces may be evaluated

Handbook of Optical and Laser Scanning

From its initial publication titled Laser Beam Scanning in 1985 to Handbook of Optical and Laser Scanning, now in its second edition, this reference has kept professionals and students at the forefront of optical scanning technology. Carefully and meticulously updated in each iteration, the book continues to be the most comprehensive scanning resource on the market. It examines the breadth and depth of subtopics in the field from a variety of perspectives. The Second Edition covers: Technologies such as piezoelectric devices Applications of laser scanning such as Ladar (laser radar) Underwater scanning and laser scanning in CTP As laser costs come down, and power and availability increase, the potential applications for laser scanning continue to increase. Bringing together the knowledge and experience of 26 authors from England, Japan and the United States, the book provides an excellent resource for understanding the principles of laser scanning. It illustrates the significance of scanning in society today and would help the user get started in developing system concepts using scanning. It can be used as an introduction to the field and as a reference for persons involved in any aspect of optical and laser beam scanning

Handbook of Optical and Laser Scanning

From its initial publication titled Laser Beam Scanning in 1985 to Handbook of Optical and Laser Scanning, now in its second edition, this reference has kept professionals and students at the forefront of optical scanning technology. Carefully and meticulously updated in each iteration, the book continues to be the most comprehensive scanning resource on the market. It examines the breadth and depth of subtopics in the field from a variety of perspectives. The Second Edition covers: Technologies such as piezoelectric devices Applications of laser scanning such as Ladar (laser radar) Underwater scanning and laser scanning in CTP As laser costs come down, and power and availability increase, the potential applications for laser scanning continue to increase. Bringing together the knowledge and experience of 26 authors from England, Japan and the United States, the book provides an excellent resource for understanding the principles of laser scanning. It illustrates the significance of scanning in society today and would help the user get started in developing system concepts using scanning. It can be used as an introduction to the field and as a reference for persons involved in any aspect of optical and laser beam scanning

Scalability of RAID systems

RAID systems (Redundant Arrays of Inexpensive Disks) have dominated backend storage systems for more than two decades and have grown continuously in size and complexity. Currently they face unprecedented challenges from data intensive applications such as image processing, transaction processing and data warehousing. As the size of RAID systems increases, designers are faced with both performance and reliability challenges. These challenges include limited back-end network bandwidth, physical interconnect failures, correlated disk failures and long disk reconstruction time. This thesis studies the scalability of RAID systems in terms of both performance and reliability through simulation, using a discrete event driven simulator for RAID systems (SIMRAID) developed as part of this project. SIMRAID incorporates two benchmark workload generators, based on the SPC-1 and Iometer benchmark specifications. Each component of SIMRAID is highly parameterised, enabling it to explore a large design space. To improve the simulation speed, SIMRAID develops a set of abstraction techniques to extract the behaviour of the interconnection protocol without losing accuracy. Finally, to meet the technology trend toward heterogeneous storage architectures, SIMRAID develops a framework that allows easy modelling of different types of device and interconnection technique. Simulation experiments were first carried out on performance aspects of scalability. They were designed to answer two questions: (1) given a number of disks, which factors affect back-end network bandwidth requirements; (2) given an interconnection network, how many disks can be connected to the system. The results show that the bandwidth requirement per disk is primarily determined by workload features and stripe unit size (a smaller stripe unit size has better scalability than a larger one), with cache size and RAID algorithm having very little effect on this value. The maximum number of disks is limited, as would be expected, by the back-end network bandwidth. Studies of reliability have led to three proposals to improve the reliability and scalability of RAID systems. Firstly, a novel data layout called PCDSDF is proposed. PCDSDF combines the advantages of orthogonal data layouts and parity declustering data layouts, so that it can not only survivemultiple disk failures caused by physical interconnect failures or correlated disk failures, but also has a good degraded and rebuild performance. The generating process of PCDSDF is deterministic and time-efficient. The number of stripes per rotation (namely the number of stripes to achieve rebuild workload balance) is small. Analysis shows that the PCDSDF data layout can significantly improve the system reliability. Simulations performed on SIMRAID confirm the good performance of PCDSDF, which is comparable to other parity declustering data layouts, such as RELPR. Secondly, a system architecture and rebuilding mechanism have been designed, aimed at fast disk reconstruction. This architecture is based on parity declustering data layouts and a disk-oriented reconstruction algorithm. It uses stripe groups instead of stripes as the basic distribution unit so that it can make use of the sequential nature of the rebuilding workload. The design space of system factors such as parity declustering ratio, chunk size, private buffer size of surviving disks and free buffer size are explored to provide guidelines for storage system design. Thirdly, an efficient distributed hot spare allocation and assignment algorithm for general parity declustering data layouts has been developed. This algorithm avoids conflict problems in the process of assigning distributed spare space for the units on the failed disk. Simulation results show that it effectively solves the write bottleneck problem and, at the same time, there is only a small increase in the average response time to user requests

Considerations for the interdisciplinary development of environmental system models

Effective decision making and policy development requires holistic consideration of the modelling context. This thesis explores how consideration of multiple disciplinary perspectives and concerns lead to an integrative model development process for the purpose of socio-environmental systems (SES) management. The research is presented through two frames: (1) Integrated Environmental Model (IEM) development through a System-of-Systems (SoS) approach, and (2) the socio-technical considerations within an interdisciplinary modelling process. The presented research incorporates the perspectives of the modelling, systems engineering, and software development paradigms. IEMs are developed for the purpose of integrating knowledge across the various disciplines involved, whereas traditional approaches focus on single systems within the SES, such as hydrology, economics, social dynamics, or climatic drivers. Use of IEMs allows for the consideration of the flow-on effects due to system changes and interaction, and how these may affect long-term SES behaviour. Pathways that are robust - i.e., lead to beneficial or desirable outcomes - under a range of plausible but uncertain conditions can then be identified and assessed. An interconnected network of system models thus makes up an SoS model allowing consideration of higher-order effects. In practice, however, the decisions and approaches taken in developing constituent models may influence integrated system behaviour once coupled. The socio-technical modelling concerns within the SoS/SES modelling context, including the methods to assess and manage model validity, complexity, and uncertainty, with respect to model purpose and intended outcomes are explored through a series of publications. This thesis contributes to the growing body of knowledge through: 1. An expansive overview of the currently available software for model uncertainty and sensitivity analysis, and the techniques they encompass 2. An integrated environmental model for the Lower Campaspe catchment in North-Central Victoria, Australia. The model explores long-term implications of water management decisions and potential policy changes (primarily through an agricultural lens), including conjunctive use of surface and groundwater under a range of uncertain futures. 3. Demonstration of a property-based sensitivity analysis approach to model diagnostics that combines software testing and sensitivity analysis to validate model behaviour. The approach is useful as a first-pass screening tool. Failure to reproduce expected model behaviour indicates issues with the model to be corrected and avoids the necessity of more computationally demanding diagnostics. 4. A pragmatic step-by-step framework for the sensitivity analysis of spatially distributed environmental models 5. Exploration and discussion of the modelling practices, issues and challenges that arise when dealing with the various influences and effects of scale within the interdisciplinary SoS context through a socio-technical lens. The discussion leads to a call for a grander vision for SoS-IEM modelling (and commensurate funding) to better enable interdisciplinary, and integrative, socio-environmental research to occur. 6. A shared reflexive account of two case studies that draws out the considerations and decisions regarding scale to arrive at five shared lessons learnt to foster an effective interdisciplinary modelling process. The key conclusion is the need for researchers involved in SoS modelling of SESs to actively consider and address cross-disciplinary concerns through improved interdisciplinary communication, documentation practices, and explicit consideration of the interplay between defined scales and resulting influence on uncertainty. Integrative consideration of these would then lower or avoid barriers that hamper the development and application of integrated environmental system models