University of Wisconsin

Displaying 81-120 of 126 results

  • White Papers // Dec 2009

    WrtVMM: A Virtual Machine Monitor for Embedded Devices

    The authors built a virtual machine monitor for the Linksys WRT54GL wireless router to run Embedded Xinu as a guest OS within OpenWrt. The system uses a kernel module and signal handlers to support the virtualization of the guest OS. Sufficient support is provided to allow Xinu to startup, handle...

    Provided By University of Wisconsin

  • White Papers // Dec 2009

    Toward Industrial-Strength Keyword Search Systems Over Relational Data

    KeyWord Search (KWS) over relational data, where the answers are multiple tuples connected via joins, has received significant attention in the past decade. Numerous solutions have been proposed and many prototypes have been developed. Building on this rapid progress and on growing user needs, recently several RDBMS and Web companies...

    Provided By University of Wisconsin

  • White Papers // Dec 2009

    Toward the Practical Use of Network Tomography for Internet Topology Discovery

    Accurate and timely identification of the router-level topology of the Internet is one of the major unresolved problems in Internet research. Topology recovery via tomographic inference is potentially an attractive complement to standard methods that use TTL-limited probes. In this paper, the authors describe new techniques that aim toward the...

    Provided By University of Wisconsin

  • White Papers // Dec 2009

    Enhancing Simulation Mode Operation of Ospfd

    In this paper, the authors describe their modifications to ospfd, a popular open-source implementation of OSPF routing protocol. The ospfd software can also be run in simulation mode, where processes, representing individual routers, communicate with each other over UDP sockets. Even though ospfd provides a fine-granularity implementation of OSPF protocol,...

    Provided By University of Wisconsin

  • White Papers // Dec 2009

    Protecting Commodity Operating System Kernels From Vulnerable Device Drivers

    Device drivers on commodity operating systems execute with kernel privilege and have unfettered access to kernel data structures. Several recent attacks demonstrate that such poor isolation exposes kernel data to exploits against vulnerable device drivers, for example through buffer overruns in packet processing code. Prior architectures to isolate kernel data...

    Provided By University of Wisconsin

  • White Papers // Nov 2009

    Cloud Computing: The Changing Face of Computer Science

    The way people use computers is changing. Instead of data and programs being contained on the device of users, they will be held on servers in a server farm, and users will access the content via the Internet for a fee. Computer usage will become a service, with the benefits...

    Provided By University of Wisconsin

  • White Papers // Oct 2009

    Impact of Disk Corruption on Open-Source DBMS

    Despite the best intentions of disk and RAID manufacturers, on-disk data can still become corrupted. This paper examines the effects of corruption on database management systems. Through injecting faults into the MySQL DBMS, the authors find that in certain cases, corruption can greatly harm the system, leading to untimely crashes,...

    Provided By University of Wisconsin

  • White Papers // Oct 2009

    Multi-Byte Regular Expression Matching With Speculation

    Intrusion prevention systems determine whether incoming traffic matches a database of signatures, where each signature in the database represents an attack or a vulnerability. IPSs need to keep up with ever-increasing line speeds, which leads to the use of custom hardware. A major bottleneck that IPSs face is that they...

    Provided By University of Wisconsin

  • White Papers // Oct 2009

    A Learning-Based Approach for IP Geolocation

    The ability to pinpoint the geographic location of IP hosts is compelling for applications such as on-line advertising and network at-tack diagnosis. While prior methods can accurately identify the location of hosts in some regions of the Internet, they produce erroneous results when the delay or topology measurement on which...

    Provided By University of Wisconsin

  • White Papers // Sep 2009

    Network Anomaly Confirmation, Diagnosis and Remediation

    Identifying and diagnosing network traffic anomalies, and rectifying their effects are standard, daily activities of network operators. While there is a large and growing literature on techniques for detecting network anomalies, there has been little or no treatment of what to do after a candidate anomaly has been identified. In...

    Provided By University of Wisconsin

  • White Papers // Sep 2009

    Towards a Model-Driven Approach for Reverse Engineering Design Patterns

    The size and complexity of software systems is rapidly increasing. Meanwhile, the ability to understand and maintain such systems is decreasing almost as fast. Model Driven Engineering (MDE) promotes the notion of modeling to cope with software complexity; in this paper the authors report on their research that utilizes ontological...

    Provided By University of Wisconsin

  • White Papers // Sep 2009

    ScalaQL: Language-Integrated Database Queries for Scala

    One of the most ubiquitous elements of modern computing is the relational database. Very few modern applications are created with-out some sort of database back-end. Unfortunately, relational database concepts are fundamentally very different from those used in general-purpose programming languages. This creates an impedance mismatch between the the application and...

    Provided By University of Wisconsin

  • White Papers // Aug 2009

    Reducing Concurrent Analysis Under a Context Bound to Sequential Analysis

    This paper addresses the analysis of concurrent programs with shared memory. Such an analysis is undecidable in the presence of multiple procedures. One approach used in recent work obtains decidability by providing only a partial guarantee of correctness: the approach bounds the number of context switches allowed in the concurrent...

    Provided By University of Wisconsin

  • White Papers // Aug 2009

    Static Verification of Data-Consistency Properties

    To leverage the increased processing power of modern multicore processors, programmers are left with the burden of writing concurrent programs. A popular language for writing concurrent programs is Java. In Java, a concurrent program consists of multiple threads that execute in parallel and communicate through shared memory. Because the number...

    Provided By University of Wisconsin

  • White Papers // Aug 2009

    Verifying Information Flow Control Over Unbounded Processes

    Decentralized Information Flow Control (DIFC) systems enable programmers to express a desired DIFC policy, and to have the policy enforced via a reference monitor that restricts interactions between system objects, such as processes and les. Past research on DIFC systems focused on the reference-monitor implementation, and assumed that the desired...

    Provided By University of Wisconsin

  • White Papers // Aug 2009

    Tolerating Hardware Device Failures in Software

    Hardware devices can fail, but many drivers assume they do not. When confronted with real devices that misbehave, these assumptions can lead to driver or system failures. While major operating system and device vendors recommend that drivers detect and recover from hardware failures, the authors find that there are many...

    Provided By University of Wisconsin

  • White Papers // Jul 2009

    Using Proximity Search to Estimate Authority Flow

    Authority flow and proximity search have been used extensively in measuring the association between entities in data graphs, ranging from the Web to relational and XML databases. These two ranking factors have been used and studied separately in the past. In addition to their semantic differences, a key advantage of...

    Provided By University of Wisconsin

  • White Papers // Jul 2009

    Light Field Video Stabilization

    The authors describe a method for producing a smooth, stabilized video from the shaky input of a hand-held light field video camera - specifically, a small camera array. Traditional stabilization techniques dampen shake with 2D warps, and thus have limited ability to stabilize a significantly shaky camera motion through a...

    Provided By University of Wisconsin

  • White Papers // Jul 2009

    An Efficient Algorithm for Co-Segmentation

    This paper is focused on the Co-segmentation problem - where the objective is to segment a similar object from a pair of images. The background in the two images may be arbitrary; therefore, simultaneous segmentation of both images must be performed with a requirement that the appearance of the two...

    Provided By University of Wisconsin

  • White Papers // Jun 2009

    On some sufficient conditions for distributed Quality-of-Service support in wireless networks

    Given a wireless network where some pairs of communication links interfere with each other, the authors study sufficient conditions for determining whether a given set of minimum bandwidth Quality of Service (QoS) requirements can be satisfied. They are especially interested in algorithms which have low communication overhead and low processing...

    Provided By University of Wisconsin

  • White Papers // Jun 2009

    Analyzing the Hold Time Schemes to Limit the Routing Table Calculations in OSPF Protocol

    OSPF is a popular interior gateway routing protocol. Commercial OSPF routers limit their processing load by using a hold time between successive routing table calculations as new Link State Advertisements (LSAs) arrive following a topology change. A large hold time value limits the frequency of routing table calculations but also...

    Provided By University of Wisconsin

  • White Papers // Jun 2009

    The Producer Cooperative As Monitored Credit? The Case Of West Liberty Foods

    The West Liberty Foods turkey cooperative formed in 1996 to purchase the assets and assume operations of Louis Rich Foods. Based on field interviews with grower members and company management, the authors describe changes in the economic relationship between growers and the company that resulted from the purchase. They argue...

    Provided By University of Wisconsin

  • White Papers // May 2009

    Manual Vs. Automated Vulnerability Assessment

    The dream of every software development team is to assess the security of their software using only a tool. In this paper, the authors attempt to evaluate and quantify the effectiveness of automated source code analysis tools by comparing such tools to the results of an in-depth manual evaluation of...

    Provided By University of Wisconsin

  • White Papers // May 2009

    Tolerating File-System Mistakes With EnvyFS

    The authors introduce EnvyFS, an N-version local file system designed to improve reliability in the face of file-system bugs. EnvyFS, implemented as a thin VFS-like layer near the top of the storage stack, replicates file-system metadata and data across existing and diverse commodity file systems (E.g., ext3, ReiserFS, JFS). It...

    Provided By University of Wisconsin

  • White Papers // May 2009

    Content-Preserving Warps for 3D Video Stabilization

    The authors describe a technique that transforms a video from a hand-held video camera so that it appears as if it were taken with a directed camera motion. The method adjusts the video to appear as if it were taken from nearby viewpoints, allowing 3D camera movements to be simulated....

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    Flash Aware RAID

    Flash based SSDs are increasing in popularity, performance, and capacity. The advancements made in capacity come at a cost of decreased reliability. Traditional error correcting codes capable of repairing single-bit errors are no longer completely effective as multiple-bit errors grow more common. Because of this, flash based storage should leverage...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    A Thread-Wise Strategy for Incremental Crawling of Web Forums

    The authors study in this paper the problem of incremental crawling of web forums, which is a very fundamental yet challenging step in many web applications. Traditional approaches mainly focus on scheduling the revisiting strategy of each individual page. However, simply assigning different weights for different individual pages are usually...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    FlashVM: Revisiting the Virtual Memory Hierarchy

    Flash memory is the largest change to storage in recent history. Most research to date has focused on integrating flash as persistent storage in file systems, with little emphasis on virtual memory paging. However, the VM architecture in most of the commodity operating systems is heavily customized for using disks...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    Decaf: Moving Device Drivers to a Modern Language

    Writing code to interact with external devices is inherently difficult, and the added demands of writing device drivers in C for kernel mode compounds the problem. This environment is complex and brittle, leading to increased development costs and, in many cases, unreliable code. Previous solutions to this problem ignore the...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    Keepin' It Real: Semi-Supervised Learning With Realistic Tuning

    The authors address two critical issues involved in applying Semi-Supervised Learning (SSL) to a real-world task: parameter tuning and choosing which (If any) SSL algorithm is best suited for the task at hand. To gain a better understanding of these issues, they carry out a medium-scale empirical study comparing Supervised...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    Proactive Attacker Localization in Wireless LAN

    This paper addresses the open problem of locating an attacker that intentionally hides or falsifies its position using advanced radio technologies. A novel attacker localization mechanism, called Access Point Coordinated Localization (APCL), is proposed for IEEE 802.11 networks. APCL actively forces the attacker to reveal its position information by combining...

    Provided By University of Wisconsin

  • White Papers // Mar 2009

    Some New Directions in Graph-Based Semi-Supervised Learning

    In this position paper, the authors first review the state-of-the-art in graph-based semi-supervised learning, and point out three limitations that are particularly relevant to multimedia analysis: Rich data is restricted to live on a single manifold; learning must happen in batch mode; and the target label is assumed smooth on...

    Provided By University of Wisconsin

  • White Papers // Mar 2009

    Symbolic Analysis Via Semantic Reinterpretation

    The paper presents a novel technique to create implementations of the basic primitives used in symbolic program analysis: forward symbolic evaluation, weakest liberal precondition, and symbolic composition. The authors used the technique to create a system in which, for the cost of writing just one specification - an interpreter for...

    Provided By University of Wisconsin

  • White Papers // Mar 2009

    Detecting and Measuring Similarity in Code Clones

    Most previous work on code-clone detection has focused on finding identical clones, or clones that are identical up to identifiers and literal values. However, it is often important to find similar clones, too. One challenge is that the definition of similarity depends on the context in which clones are being...

    Provided By University of Wisconsin

  • White Papers // Feb 2009

    Evaluating GPUs for Network Packet Signature Matching

    Modern network devices employ deep packet inspection to enable sophisticated services such as intrusion detection, traffic shaping, and load balancing. At the heart of such services is a signature matching engine that must match packet payloads to multiple signatures at line rates. However, the recent transition to complex regular-expression based...

    Provided By University of Wisconsin

  • White Papers // Feb 2009

    Unraveling the Complexity of Network Management

    Operator interviews and anecdotal evidence suggest that an operator's ability to manage a network decreases as the network becomes more complex. However, there is currently no way to systematically quantify how complex a network's design is nor how complexity may impact network management activities. This paper develops a suite of...

    Provided By University of Wisconsin

  • White Papers // Feb 2009

    On the Effectiveness of Pre-Acceptance Spam Filtering

    Modern SMTP servers apply a variety of mechanisms to stem the volume of spam delivered to users. These techniques can be broadly classified into two categories: pre-acceptance approaches, which apply prior to a message being accepted (e.g. blacklisting and whitelisting), and post-acceptance techniques which apply after a message has been...

    Provided By University of Wisconsin

  • White Papers // Jan 2009

    Estimating Hop Distance Between Arbitrary Host Pairs

    Establishing a clear and timely picture of Internet topology is complicated by many factors including the vast size and dynamic nature of the infrastructure. In this paper, the authors describe a methodology for estimating an important characteristic of Internet topology - the hop distance between arbitrary pairs of end hosts....

    Provided By University of Wisconsin

  • White Papers // Jan 2009

    Network Performance Anomaly Detection and Localization

    Detecting the occurrence and location of performance anomalies (e.g., High jitter or loss events) is critical to ensuring the effective operation of network infrastructures. In this paper the authors present a framework for detecting and localizing performance anomalies based on using an active probe-enabled measurement infrastructure deployed on the periphery...

    Provided By University of Wisconsin

  • White Papers // Jan 2009

    Mass Collaboration Systems on the World-Wide Web

    Mass collaboration systems enlist a multitude of humans to help solve a wide variety of problems. Over the past decade, numerous such systems have appeared on the World Wide Web. Prime examples include Wikipedia, Linux, Yahoo! Answers, Amazon's Mechanical Turk, and much effort is being directed at developing many more....

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Caching for Multi-Dimensional Data Mining Queries

    Multi-dimensional data analysis and online analytical processing are standard querying techniques applied on today's data warehouses. Data mining algorithms, on the other hand, are mostly run in stand-alone, batch mode on at les extracted from relational databases. In this paper the authors propose a general querying model combining the power...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Multiprocessor Scheduling Using Dynamic Performance Measurement and Analysis

    In this paper the authors address using dynamic performance metrics when making scheduling decisions. The focus is on the problem of cache affinity in multiprocessor CPU schedulers. The Linux 2.4 kernel uses a simplistic method to determine cache affinity, one that does not take into account the working set size...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Program Generalization for Software Reuse: From C to C++

    The authors consider the problem of software generalization: Given a program component C, create a parameterized program component C' such that C' is usable in a wider variety of syntactic contexts than C. Furthermore, C' should be a semantically meaningful generalization of C; namely, there must exist an instantiation of...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Modeling Congestion in Backbone Routers

    Traffic engineering models based on end-to-end loss probabilities and delays do not scale well to fast backbone links. In this paper, the authors investigate the nature of congestion events in highly aggregated flows. An examination of congestion events shows distinct phases of queue buildup, packet dropping followed later by TCP...

    Provided By University of Wisconsin

  • White Papers // Aug 2010

    Accelerated Block-Coordinate Relaxation for Regularized Optimization

    The authors discuss minimization of a smooth function to which is added a regularization function that induces structure in the solution. A block-coordinate relaxation approach with proximal linearized subproblems yields convergence to stationary points, while identification of the optimal manifold (Under a nondegeneracy condition) allows acceleration techniques to be applied...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Inferring Regulatory Networks From Time Series Expression Data and Relational Data Via Inductive Logic Programming

    In this paper, the authors are interested in learning rules that will reveal the causal genes for the expression variation from various relational data sources in addition to gene expression data. Following the previous work where they showed that time series gene expression data could potentially uncover causal effects, they...

    Provided By University of Wisconsin

  • White Papers // Dec 2010

    Identifying Activity

    Identification of active constraints in constrained optimization is of interest from both practical and theoretical viewpoints, as it holds the promise of reducing an inequality-constrained problem to an equality-constrained problem, in a neighborhood of a solution. The authors study this issue in the more general setting of composite nonsmooth minimization,...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    A Thread-Wise Strategy for Incremental Crawling of Web Forums

    The authors study in this paper the problem of incremental crawling of web forums, which is a very fundamental yet challenging step in many web applications. Traditional approaches mainly focus on scheduling the revisiting strategy of each individual page. However, simply assigning different weights for different individual pages are usually...

    Provided By University of Wisconsin

  • White Papers // Dec 2010

    Tuffy: Scaling Up Statistical Inference in Markov Logic Networks

    Markov Logic Networks (MLNs) have emerged as a powerful framework that combines statistical and logical reasoning; they have been applied to many data intensive problems including information extraction, entity resolution, and text mining. Current implementations of MLNs do not scale to real-world data sets, which is preventing their wide-spread adoption....

    Provided By University of Wisconsin

  • White Papers // Sep 2009

    Network Anomaly Confirmation, Diagnosis and Remediation

    Identifying and diagnosing network traffic anomalies, and rectifying their effects are standard, daily activities of network operators. While there is a large and growing literature on techniques for detecting network anomalies, there has been little or no treatment of what to do after a candidate anomaly has been identified. In...

    Provided By University of Wisconsin

  • White Papers // Mar 2009

    Symbolic Analysis Via Semantic Reinterpretation

    The paper presents a novel technique to create implementations of the basic primitives used in symbolic program analysis: forward symbolic evaluation, weakest liberal precondition, and symbolic composition. The authors used the technique to create a system in which, for the cost of writing just one specification - an interpreter for...

    Provided By University of Wisconsin

  • White Papers // Aug 2009

    Reducing Concurrent Analysis Under a Context Bound to Sequential Analysis

    This paper addresses the analysis of concurrent programs with shared memory. Such an analysis is undecidable in the presence of multiple procedures. One approach used in recent work obtains decidability by providing only a partial guarantee of correctness: the approach bounds the number of context switches allowed in the concurrent...

    Provided By University of Wisconsin

  • White Papers // Jul 2009

    Light Field Video Stabilization

    The authors describe a method for producing a smooth, stabilized video from the shaky input of a hand-held light field video camera - specifically, a small camera array. Traditional stabilization techniques dampen shake with 2D warps, and thus have limited ability to stabilize a significantly shaky camera motion through a...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    The Design, Implementation, and Evaluation of mpiBLAST

    mpiBLAST is an open-source parallelization of BLAST that achieves superlinear speed-up by segmenting a BLAST database and then having each node in a computational cluster search a unique portion of the database. Database segmentation permits each node to search a smaller portion of the database, eliminating disk I/O and vastly...

    Provided By University of Wisconsin

  • White Papers // Jan 2009

    Estimating Hop Distance Between Arbitrary Host Pairs

    Establishing a clear and timely picture of Internet topology is complicated by many factors including the vast size and dynamic nature of the infrastructure. In this paper, the authors describe a methodology for estimating an important characteristic of Internet topology - the hop distance between arbitrary pairs of end hosts....

    Provided By University of Wisconsin

  • White Papers // Jul 2009

    An Efficient Algorithm for Co-Segmentation

    This paper is focused on the Co-segmentation problem - where the objective is to segment a similar object from a pair of images. The background in the two images may be arbitrary; therefore, simultaneous segmentation of both images must be performed with a requirement that the appearance of the two...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Locking Protocols for Materialized Aggregate Join Views

    The maintenance of materialized aggregate join views is a well-studied problem. However, to date the published literature has largely ignored the issue of concurrency control. Clearly immediate materialized view maintenance with transactional consistency, if enforced by generic concurrency control mechanisms, can result in low levels of concurrency and high rates...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Formalizing Sensitivity in Static Analysis for Intrusion Detection

    A key function of a host-based intrusion detection system is to monitor program execution. Models constructed using static analysis have the highly desirable feature that they do not produce false alarms; however, they may still miss attacks. Prior work has shown a trade-off between efficiency and precision. In particular, the...

    Provided By University of Wisconsin

  • White Papers // Jan 2011

    Trace Cache: A Low Latency Approach to High Bandwidth Instruction Fetching

    As the issue width of superscalar processors is increased, instruction fetch bandwidth requirements will also increase. It will become necessary to fetch multiple basic blocks per cycle. Conventional instruction caches hinder this effort because long instruction sequences are not always in contiguous cache locations. The authors propose supplementing the conventional...

    Provided By University of Wisconsin

  • White Papers // Oct 2008

    Mostly-Functional Behavior in Java Programs

    This paper presents a lightweight type-and-effect system for Java programs that features two major innovations over extant object-oriented effects systems: initialization effects, which are writes to an object's state while it is being constructed, and quiescing fields, which are fields that are never written after an object is constructed. The...

    Provided By University of Wisconsin

  • White Papers // Jan 2009

    Accurate and Efficient Mode Acceleration Data Recovery for Superelement Models

    Procedures are described for accurate and efficient mode acceleration data recovery of transient responses for superelement models. The procedures are more accurate than MSC/NASTRAN's standard mode acceleration data recovery method for large super-element models. The procedures are very efficient for large models with few load vectors and large numbers of...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    Proactive Attacker Localization in Wireless LAN

    This paper addresses the open problem of locating an attacker that intentionally hides or falsifies its position using advanced radio technologies. A novel attacker localization mechanism, called Access Point Coordinated Localization (APCL), is proposed for IEEE 802.11 networks. APCL actively forces the attacker to reveal its position information by combining...

    Provided By University of Wisconsin

  • White Papers // Feb 2009

    Unraveling the Complexity of Network Management

    Operator interviews and anecdotal evidence suggest that an operator's ability to manage a network decreases as the network becomes more complex. However, there is currently no way to systematically quantify how complex a network's design is nor how complexity may impact network management activities. This paper develops a suite of...

    Provided By University of Wisconsin

  • White Papers // Apr 2010

    Extensible and Scalable Network Monitoring Using OpenSAFE

    Administrators of today's networks are highly interested in monitoring traffic for purposes of collecting statistics, detecting intrusions, and providing forensic evidence. Unfortunately, network size and complexity can make this a daunting task. Aside from the problems in analyzing network traffic for this information - an extremely difficult task itself -...

    Provided By University of Wisconsin

  • White Papers // Nov 2009

    Cloud Computing: The Changing Face of Computer Science

    The way people use computers is changing. Instead of data and programs being contained on the device of users, they will be held on servers in a server farm, and users will access the content via the Internet for a fee. Computer usage will become a service, with the benefits...

    Provided By University of Wisconsin

  • White Papers // Jan 2010

    Scientific Workflow Management by Database Management

    In several working environments, production involves repeated executions of certain procedures. A workflow describes the individual tasks performed in these procedures and their interrelationships. Current Workflow Management Systems (WFMSs) use a Database Management System (DBMS) to store task descriptions, and implement all workflow functionality in modules that run on top...

    Provided By University of Wisconsin

  • White Papers // Jan 2010

    Laying the Foundation for the Investigation of the Quality of Service for Resource Management in Grid Computing

    By pooling the resources of virtually any functional machine, grids have quickly become a powerful, low-cost, attractive solution in a number of application domains. As a result of the surge in interest in grid computing, a variety of implementations have emerged. The availability of grid systems in commercial industry is...

    Provided By University of Wisconsin

  • White Papers // Jan 2010

    Nest - A Grid Enabled Storage Appliance

    This paper describes NeST, a flexible software-only storage appliance designed to meet the storage needs of the Grid. NeST has three key features that make it well suited for deployment in a Grid environment. First, NeST provides a generic data transfer architecture that supports multiple data transfer protocols including GridFTP...

    Provided By University of Wisconsin

  • White Papers // Jan 2010

    Phase III: Data Recovery and Mitigation

    Data recovery may be undertaken as a form of mitigation at an archeological site determined eligible for listing on the National Register of Historic Places and that will be impacted by a proposed federal undertaking. Data recovery is undertaken when neither preservation in place nor avoidance through project redesign is...

    Provided By University of Wisconsin

  • White Papers // Jan 2010

    A DBMS Engine Simulator to Assist in Classroom Understanding of Oracle Query Execution

    Oracle's DBMS query execution process consists of a complicated series of steps which can be difficult for many students and professionals to understand. It is also difficult to find resources which provide a compiled description of this process and all of the components involved. The authors have researched Oracle's DBMS...

    Provided By University of Wisconsin

  • White Papers // Oct 2009

    Impact of Disk Corruption on Open-Source DBMS

    Despite the best intentions of disk and RAID manufacturers, on-disk data can still become corrupted. This paper examines the effects of corruption on database management systems. Through injecting faults into the MySQL DBMS, the authors find that in certain cases, corruption can greatly harm the system, leading to untimely crashes,...

    Provided By University of Wisconsin

  • White Papers // Mar 2010

    Peeking Into the Cloud: Toward User-Driven Cloud Management

    The emergence and growing popularity of cloud computing signals an evolution in the way IT infrastructure and services are delivered and consumed. Cloud services have a number of essential characteristics, such as self-service on-demand consumption, location independence, and rapid elasticity. There are also evolving cloud delivery models, including Infrastructure-as-a-Service (IaaS),...

    Provided By University of Wisconsin

  • White Papers // Dec 2009

    Multi-View 3D Geometry Reconstruction: Exploiting Massive Parallelism

    3D geometric reconstruction from digital images captured from consumer cameras is an inexpensive, but computationally demanding application. In this experimental study, the authors have explored parallelism in the best known public domain software (Bundler and PMVS2) and found that massive parallelism exists at various levels that can be exploited on...

    Provided By University of Wisconsin

  • White Papers // Nov 2008

    Live Migration of Direct-Access Devices

    Virtual machine migration greatly aids management by allowing flexible provisioning of resources and decommissioning of hardware for maintenance. However, efforts to improve network performance by granting virtual machines direct access to hardware currently prevent migration. This occurs because the VMM cannot migrate the state of the device, and the source...

    Provided By University of Wisconsin

  • White Papers // Dec 2008

    Scalable Distributed Process Group Control and Inspection via the File System

    The size of distributed systems is rapidly expanding to meet the computational demands of the world. The largest current distributed systems for corporate intranets, High-Performance Computing (HPC) systems, and cloud computers contain tens of thousands of hosts. HPC systems on the horizon are expected to have counts in the millions....

    Provided By University of Wisconsin

  • White Papers // Jun 2010

    The Case for Fine-Grained Traffic Engineering in Data Centers

    In recent years, several techniques have been suggested for routing and traffic engineering in data centers. However, not much is known about how these techniques perform relative to each other under realistic data center traffic patterns. The preliminary study reveals that existing techniques can only achieve 80% to 85% of...

    Provided By University of Wisconsin

  • White Papers // Apr 2009

    Keepin' It Real: Semi-Supervised Learning With Realistic Tuning

    The authors address two critical issues involved in applying Semi-Supervised Learning (SSL) to a real-world task: parameter tuning and choosing which (If any) SSL algorithm is best suited for the task at hand. To gain a better understanding of these issues, they carry out a medium-scale empirical study comparing Supervised...

    Provided By University of Wisconsin

  • White Papers // Mar 2010

    Model Evolution: An Incremental Approach to Non-Rigid Structure From Motion

    In this paper, the authors present a new framework for Non-Rigid Structure From Motion (NRSFM) that simultaneously addresses three significant challenges: severe occlusion, perspective camera projection, and large non-linear deformation. They introduce a concept called a model graph, which greatly reduces the computational cost of discovering groups of input images...

    Provided By University of Wisconsin

  • White Papers // Jun 2010

    Dynamic Processors Demand Dynamic Operating Systems

    The rise of multicore processors has lead to techniques that dynamically vary the set and characteristics of cores or threads available to the operating system. For example, Core Fusion merges multiple cores for faster processing. While the mechanics of the change, such as merging two cores into a more powerful...

    Provided By University of Wisconsin

  • White Papers // Dec 2009

    WrtVMM: A Virtual Machine Monitor for Embedded Devices

    The authors built a virtual machine monitor for the Linksys WRT54GL wireless router to run Embedded Xinu as a guest OS within OpenWrt. The system uses a kernel module and signal handlers to support the virtualization of the guest OS. Sufficient support is provided to allow Xinu to startup, handle...

    Provided By University of Wisconsin