On Benchmarking Embedded Linux Flash File Systems

Due to its attractive characteristics in terms of performance, weight and power consumption, NAND flash memory became the main non volatile memory (NVM) in embedded systems. Those NVMs also present some specific characteristics/constraints: good but asymmetric I/O performance, limited lifetime, write/erase granularity asymmetry, etc. Those peculiarities are either managed in hardware for flash disks (SSDs, SD cards, USB sticks, etc.) or in software for raw embedded flash chips. When managed in software, flash algorithms and structures are implemented in a specific flash file system (FFS). In this paper, we present a performance study of the most widely used FFSs in embedded Linux: JFFS2, UBIFS,and YAFFS. We show some very particular behaviors and large performance disparities for tested FFS operations such as mounting, copying, and searching file trees, compression, etc.Comment: Embed With Linux, Lorient : France (2012

CSR: Small: Collaborative Research: SANE: Semantic-Aware Namespace in Exascale File Systems

Explosive growth in volume and complexity of data exacerbates the key challenge facing the management of massive data in a way that fundamentally improves the ease and efficacy of their usage. Exascale storage systems in general rely on hierarchically structured namespace that leads to severe performance bottlenecks and makes it hard to support real-time queries on multi-dimensional attributes. Thus, existing storage systems, characterized by the hierarchical directory tree structure, are not scalable in light of the explosive growth in both the volume and the complexity of data. As a result, directory-tree based hierarchical namespace has become restrictive, difficult to use, and limited in scalability for today\u27s large-scale file systems. This project investigates a novel semantic-aware namespace scheme to provide dynamic and adaptive namespace management and support typical file-based operations in Exascale file systems. The project leverages semantic correlations among files and exploits the evolution of metadata attributes to support customized namespace management, with the end goal of efficiently facilitating file identification and end users data lookup. This project provides significant performance improvements for existing file systems in Exascale file systems. Since Exascale file systems constitute one of the backbones of the high-performance computing infrastructure, the semantic-aware techniques also benefits a great number of scientific and engineering data-intensive applications. This project strengthens the ongoing development of high performance computing infrastructures at both UNL and UMaine. The project enhances undergraduate and graduate education at both participating institutions and outreach to K-12 in UMaine via an ongoing NSF-funded ITEST program

A Case Study of Applied Co-Design in 3D Virtual Space for Facilitating Bicycle Use on Light Rail Systems

Cycling is highly recommended by experts concerned with environmental and public health. Cycling does not produce CO2 emissions, can be economical, and can improve physical fitness. However, the barriers to cycling remain significant to many. Combined with a light rail system the bicycle offers a compelling alternative to automobiles; yet, bicycles are denied access on certain rail systems because they can take too much space away from pedestrians who share the light rail interior. To help solve this problem, Co-Design in 3D virtual space is proposed as an effective means of creating an innovative design solution. The digital questionnaires and virtual 3D modeling research/design method used in this study gives the participant the ability to offer insights and express ideas through digital means and in 3D virtual space. This method, Co-Design in Virtual Space (CoDeViS), was developed by the author. CoDeViS methods are an outgrowth of physical co-design methods such as 2D collages and 3D Velcro modeling, developed by those featured in The International Journal of CoCreation in Design and the Arts. Physical 3D methods have been widely accepted in the new product development industry as effective ways to involve people outside a design team in the research and design process. CoDeViS methods offer promise to those seeking to make the principles of co-design available to larger groups of people in discrete locations around the world at lower cost. Historical developments, current technology, and the abilities of everyday people make CoDeViS possible.</p

A forensics overview and analysis of USB flash memory devices

Current forensic tools for examination of embedded systems like mobile phones and PDAs mostly perform data extraction on a logical level and do not consider the type of storage media during data analysis. This report suggests different low level approaches for the forensic examination of flash memories and describes three lowlevel data acquisition methods for making full memory copies of flash memory devices. Results of a file system study in which USB memory sticks from 45 different make and models were used are presented. For different mobile phones, this paper shows how full memory copies of their flash memories can be made and which steps are needed to translate the extracted data into a format that can be understood by common forensic media analysis tools. Artefacts, caused by flash specific operations like block erasing and wear levelling, are discussed and directions are given for enhanced data recovery and analysis of data originating from flash memory

Assured Android Execution Environments

Current cybersecurity best practices, techniques, tactics and procedures are insufficient to ensure the protection of Android systems. Software tools leveraging formal methods use mathematical means to assure both a design and implementation for a system and these methods can be used to provide security assurances. The goal of this research is to determine methods of assuring isolation when executing Android software in a contained environment. Specifically, this research demonstrates security properties relevant to Android software containers can be formally captured and validated, and that an implementation can be formally verified to satisfy a corresponding specification. A three-stage methodology called The Formal Verification Cycle is presented. This cycle focuses on the iteration over a set of security properties to validate each within a specification and their verification within a software implementation. A security property can be validated when its functional language prototype (e.g. a Haskell coded version of the property) is converted and processed by a formal method (e.g. a theorem proof assistant). This validation of the property enables the definition of the property in a software specification, which can be implemented separately in an imperative programming language (e.g. the Go programming language). Once the implementation is complete another formal method can be used (e.g. symbolic execution) to verify the imperative implementation satisfies the validated specification. Successful completion of this cycle shows a given implementation is equivalent to a functional language prototype, and this cycle assures a specification for the original desired security properties was properly implemented. This research shows an application of this cycle to develop Assured Android Execution Environments

Enterprise Vault and Discovery Accelerator: Email Archiving and Discovery Solution Implementation and the Legal Landscape

One of the most pressing Information Technology challenges organizations are facing today is managing the vast amount of data that exist at their company, especially with regard to email data. Over the last decade many legal regulations have been passed and amended to address these growing data concerns, especially with regard to email, as they contain critical business communications. These regulations require organizations to be able to quickly and accurately search and recover email data related to legal proceedings, which has led to an overwhelming adoption of email archiving and recovery solutions. Email archiving and recovery solutions allow organizations to manage their email data in an uncompromised format, to be able to meet complex and detailed legal search requests and to comply with all the varied legal regulations. Enterprise Vault and Discovery Accelerator is a leading product suite that provides email archiving, search and recovery functionality. This thesis uses the qualitative and design research methodologies to determine how Enterprise Vault and Discovery Accelerator are able to address the legal landscape that organizations are faced with today