Association for Computing Machinery

Displaying 161-200 of 6794 results

  • White Papers // Nov 2013

    Efficient and Customizable Data Partitioning Framework for Distributed Big RDF Data Processing in the Cloud

    Big data business can leverage and benefit from the clouds; the most optimized, shared, automated, and virtualized computing infrastructures. One of the important challenges in processing big data in the clouds is how to effectively partition the big data to ensure efficient distributed processing of the data. In this paper...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Using Simulation to Explore Distributed Key-Value Stores for Extreme-Scale System Services

    Owing to the significant high rate of component failures at extreme scales, system services will need to be failure-resistant, adaptive and self-healing. A majority of HPC services are still designed around a centralized paradigm and hence are susceptible to scaling issues. Peer-To-Peer (P2P) services have proved themselves at scale for...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Exploiting Application Dynamism and Cloud Elasticity for Continuous Dataflows

    Contemporary continuous data flow systems use elastic scaling on distributed cloud resources to handle variable data rates and to meet applications' needs while attempting to maximize resource utilization. However, virtualized clouds present an added challenge due to the variability in resource performance - over time and space - thereby impacting...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Exploring DRAM Organizations for Energy-Efficient and Resilient Exascale Memories

    The power target for exa-scale supercomputing is 20MW, with about 30% budgeted for the memory subsystem. Commodity DRAMs will not satisfy this requirement. Additionally, the large number of memory chips (>10M) required will result in crippling failure rates. Although specialized DRAM memories have been reorganized to reduce power through 3D-stacking...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Using Automated Performance Modeling to Find Scalability Bugs in Complex Codes

    Many parallel applications suffer from latent performance limitations that may prevent them from scaling to larger machine sizes. Often, such scalability bugs manifest themselves only when an attempt to scale the code is actually being made - a point where remediation can be difficult. However, creating analytical performance models that...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Investigating Applications Portability with the Uintah DAG-Based Runtime System on PetaScale Supercomputers

    Present trends in high performance computing present formidable challenges for applications code using multicore nodes possibly with accelerators and/or co-processors and reduced memory while still attaining scalability. Software frameworks that execute machine independent applications code using a runtime system that shields users from architectural complexities offer a possible solution. The...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Scalable Parallel OPTICS Data Clustering Using Graph Algorithmic Techniques

    Clustering is a data mining technique that groups data into meaningful subclasses, known as clusters, such that it minimizes the intra-differences and maximizes inter-differences of these subclasses. For the purpose of knowledge discovery, it identifies dense and sparse regions and therefore, discovers overall distribution patterns and correlations in the data....

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Coordinated Energy Management in Heterogeneous Processors

    In this paper the authors examine energy management in a heterogeneous processor consisting of an integrated CPU-GPU for High-Performance Computing (HPC) applications. Energy management for HPC applications is challenged by their uncompromising performance requirements and complicated by the need for coordinating energy management across distinct core types - a new...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Tera-Scale 1D FFT With Low-Communication Algorithm and Intel R Xeon Phi Coprocessors

    In this paper, the authors demonstrate the first tera-scale performance of Intel Xeon Phi coprocessors on 1D FFT computations. Applying a disciplined performance programming methodology of sound algorithm choice, valid performance model, and well-executed optimizations, they break the tera-flop mark on a mere 64 nodes of Xeon Phi and reach...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Performance Evaluation of Intel Transactional Synchronization Extensions for High-Performance Computing

    Due to limits in technology scaling, software developers have come to rely on thread-level parallelism to obtain sustainable performance improvement. However, except for the case where the computation is massively parallel (e.g., data-parallel applications), performance of threaded applications is often limited by how inter-thread synchronization is performed. For example, using...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Location-Aware Cache Management for Many-Core Processors with Deep Cache Hierarchy

    As cache hierarchies become deeper and the number of cores on a chip increases, managing caches becomes more important for performance and energy. However, current hardware cache management policies do not always adapt optimally to the applications behavior: e.g., caches may be polluted by data structures whose locality cannot be...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Practical Nonvolatile Multilevel-Cell Phase Change Memory

    Multi-Level Cell (MLC) Phase Change Memory (PCM) may provide both high capacity main memory and faster-than-Flash persistent storage. But slow growth in cell resistance with time, resistance drift, can cause transient errors in MLC-PCM. Drift errors increase with time, and prior work suggests refresh before the cell loses data. The...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Analysis of Computing and Energy Performance of Multicore, NUMA, and Manycore Platforms for an Irregular Application

    The exponential growth in processor performance seems to have reached a turning point. Now-a-days, energy efficiency is as important as performance and has become a critical aspect to the development of scalable systems. These strict energy constraints paved the way for the development of multi and manycore processors. Research on...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Cost-Aware Cloud Bursting for Enterprise Applications

    The high cost of provisioning resources to meet peak application demands has led to the widespread adoption of pay-as-you-go cloud computing services to handle workload fluctuations. Some enterprises with existing IT infrastructure employ a hybrid cloud model where the enterprise uses its own private resources for the majority of its...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Asynchronous Object Storage with QoS for Scientific and Commercial Big Data

    In this paper, the authors present their design for an asynchronous object storage system intended for use in scientific and commercial big data workloads. Use cases from the target workload do-mains are used to motivate the key abstractions used in the Application Programming Interface (API). The architecture of the Scalable...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    The Energy Case for Graph Processing on Hybrid CPU and GPU Systems

    This paper investigates the power, energy, and performance characteristics of large-scale graph processing on hybrid (i.e., CPU and GPU) single-node systems. Graph processing can be accelerated on hybrid systems by properly mapping the graph-layout to processing units, such that the algorithmic tasks exercise each of the units where they perform...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Modeling and Implementation of Energy Neutral Sensing Systems

    Energy Neutral Sensing Systems (ENSSys) achieve long-time operation by combining energy-harvesting hardware with software that regulates energy saving and spending. However, simply managing the energy resources is not the goal in itself. The authors present the modeling, implementation, and evaluation of a single wireless sensor network that executes energy-harvesting algorithms...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Supporting Complex Queries and Access Policies for Multi-user Encrypted Databases

    Cloud computing is an emerging paradigm offering companies (virtually) unlimited data storage and computation at attractive costs. It is a cost-effective model because it does not require deployment and maintenance of any dedicated IT infrastructure. Despite its benefits, it introduces new challenges for protecting the confidentiality of the data. Sensitive...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Elligator: Elliptic-Curve Points Indistinguishable from Uniform Random Strings

    Censorship-circumvention tools are in an arms race against censors. The censors study all traffic passing into and out of their controlled sphere, and try to disable censorship circumvention tools without completely shutting down the Internet. Tools aim to shape their traffic patterns to match unblocked programs, so that simple traffic...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    PHANTOM: Practical Oblivious Computation in a Secure Processor

    Confidentiality of data is a major concern for enterprises and individuals who wish to offload computation to the cloud. In particular, cloud operators have physical access to machines and can observe sensitive information (data and code) as it moves between a CPU and physical memory. In response to such attacks,...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    HIFS: History Independence for File Systems

    Ensuring complete irrecoverability of deleted data is difficult to achieve in modern systems. Simply overwriting data or deploying encryption with ephemeral keys is not sufficient. The mere (previous) existence of deleted records impacts the current system state implicitly at all layers. This can be used as an oracle to derive...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    A Parallel Spatial Data Analysis Infrastructure for the Cloud

    Spatial data analysis applications are emerging from a wide range of domains such as building information management, environmental assessments and medical imaging. Time-consuming computational geometry algorithms make these applications slow, even for medium-sized datasets. At the same time, there is a rapid expansion in available processing cores, through multi-core machines...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    The Price of Generality in Spatial Indexing

    Efficient indexing can significantly speed up the processing of large volumes of spatial data in many BigData applications. Many new emerging spatial applications (e.g., biomedical imaging, genome analysis, etc.) have varying indexing requirements, thus, a unified indexing infrastructure for implementing new indexing schemes without requiring knowledge of database internals is...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    FPDetective: Dusting the Web for Fingerprinters

    In the modern web, the browser has emerged as the vehicle of choice, which users are to trust, customize, and use, to access a wealth of information and online services. However, recent studies show that the browser can also be used to invisibly fingerprint the user: a practice that may...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Impact of Integrity Attacks on Real-Time Pricing in Smart Grids

    Modern information and communication technologies used by smart grids are subject to cyber security threats. This paper studies the impact of integrity attacks on Real-Time Pricing (RTP), a key feature of smart grids that uses such technologies to improve system efficiency. Recent studies have shown that RTP creates a closed...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    On the Security of TLS Renegotiation

    The Transport Layer Security (TLS) protocol is the most widely used security protocol on the Internet. It supports negotiation of a wide variety of cryptographic primitives through different cipher suites, various modes of client authentication, and additional features such as renegotiation. Despite its widespread use, only recently has the full...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    AppIntent: Analyzing Sensitive Data Transmission in Android for Privacy Leakage Detection

    Android phones often carry personal information, attracting malicious developers to embed code in Android applications to steal sensitive data. With known techniques in the literature, one may easily determine if sensitive data is being transmitted out of an Android phone. However, transmission of sensitive data in itself does not necessarily...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    POSTER - TRIPLEX: Verifying Data Minimisation in Communication Systems

    The main idea behind the TRIPLEX framework is to analyze relevant privacy aspects of privacy-enhancing protocols in a specified scenario that may involve several actors and protocol instances (of different protocols). Systems dealing with personal information are legally required to satisfy the principle of data minimization. Privacy-enhancing protocols use cryptographic...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Secure Data Deletion From Persistent Media

    Secure deletion is the task of deleting data irrecoverably from a physical medium. In this paper, the authors present a general approach to the design and analysis of secure deletion for persistent storage that relies on encryption and key wrapping. They define a key disclosure graph that models the adversarial...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Sparrow: Distributed, Low Latency Scheduling

    Large-scale data analytics frameworks are shifting towards shorter task durations and larger degrees of parallelism to provide low latency. Scheduling highly parallel jobs that complete in hundreds of milliseconds poses a major challenge for task schedulers, which will need to schedule millions of tasks per second on appropriate machines while...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    ROOT: Replaying Multithreaded Traces with Resource-Oriented Ordering

    The authors describe ROOT, a new method for incorporating the nondeterministic I/O behavior of multithreaded applications into trace replay. ROOT is the application of Resource-Oriented Ordering to Trace replay: actions involving a common resource are replayed in an order similar to that of the original trace. ROOT is based on...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Towards Efficient, Portable Application-Level Consistency

    Applications employ complex protocols to ensure consistency after system crashes. Such protocols are affected by the exact behavior of file systems. However, modern file systems vary widely in such behavior, reducing the correctness and performance of applications. In this paper, the authors study application-level crash consistency. Through the detailed study...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Optimistic Crash Consistency

    The authors introduce optimistic crash consistency, a new approach to crash consistency in journaling file systems. Using an array of novel techniques, they demonstrate how to build an optimistic commit protocol that correctly recovers from crashes and delivers high performance. They implement this optimistic approach within a Linux ext4 variant...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    From ARIES to MARS: Transaction Support for Next-Generation, Solid-State Drives

    Transaction-based systems often rely on Write-Ahead Logging (WAL) algorithms designed to maximize performance on disk-based storage. However, emerging fast, byte-addressable, Non-Volatile Memory (NVM) technologies (e.g., phase-change memories, spin-transfer torque MRAMs, and the memristor) present very different performance characteristics, so blithely applying existing algorithms can lead to disappointing performance. This paper...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Consistency-Based Service Level Agreements for Cloud Storage

    Choosing a cloud storage system and specific operations for reading and writing data requires developers to make decisions that trade off consistency for availability and performance. Applications may be locked into a choice that is not ideal for all clients and changing conditions. Pileus is a replicated key-value store that...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    A Locality-Aware Memory Hierarchy for Energy-Efficient GPU Architectures

    As GPU's compute capabilities grow, their memory hierarchy increasingly becomes a bottleneck. Current GPU memory hierarchies use coarse-grained memory accesses to exploit spatial locality, maximize peak bandwidth, simplify control, and reduce cache meta-data storage. These coarse-grained memory accesses, however, are a poor match for emerging GPU applications with irregular control...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Timecard: Controlling User-Perceived Delays in Server-Based Mobile Applications

    Providing consistent response times to users of mobile applications is challenging because there are several variable delays between the start of a user's request and the completion of the response. These delays include location lookup, sensor data acquisition, radio wake-up, network transmissions, and processing on both the client and server....

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    VirtuOS: An Operating System With Kernel Virtualization

    Most operating systems provide protection and isolation to user processes, but not to critical system components such as device drivers or other system code. Consequently, failures in these components often lead to system failures. VirtuOS is an operating system that exploits a new method of decomposition to protect against such...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Exposing and Mitigating Privacy Loss in Crowdsourced Survey Platforms

    Academic and market researchers are increasingly using online platforms for crowd-sourcing survey information from online users. Crowd-sourcing platforms such as Amazon mechanical turk and Google consumer surveys can profile users based on their inputs to online surveys. In this paper the authors first demonstrate how easily user privacy can be...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2013

    Distributed Privacy-Preserving Transparency Logging

    The authors present a transparency-enhancing tool in the form of a cryptographic scheme that enables data processors to inform users about the actual data processing that takes place on their personal data. Their proposed solution can handle arbitrary processes while offloading storage and interactions with users to dedicated log servers....

    Provided By Association for Computing Machinery

  • White Papers // Sep 2010

    Dynamically Managed Multithreaded Reconfigurable Architectures for Chip Multiprocessors

    Prior work has demonstrated that reconfigurable logic can significantly benefit certain applications. However, reconfigurable architectures have traditionally suffered from high area overhead and limited application coverage. This paper presents a dynamically managed multithreaded reconfigurable architecture consisting of multiple clusters of shared reconfigurable fabrics that greatly reduces the area overhead of...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2009

    Online Application Upgrade Using Edition-Based Redefinition

    Many database applications have a very High Availability (HA) requirement. Examples include electrical and telecommunication utility management systems. Those systems must be available all the time to manage the systems; for electrical utility system, it includes adjusting production, or energy trading. Another example is global customer support system for companies...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2009

    Efficient Systematic Testing for Dynamically Updatable Software

    Recent years have seen significant advances in Dynamic Software Updating (DSU) systems, which allow programs to be patched on the fly. However, a significant challenge remains: How can the authors ensure the act of applying a patch does not itself introduce errors? In this paper, they address this problem by...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2009

    Cooperative Update: A New Model for Dependable Live Update

    Many real-world systems require continuous operation. Downtime is ill-affordable and scheduling maintenance for regular software updates is a tremendous challenge for system administrators. For this reason, live update is a potential solution as it allows running software to be replaced by a newer version without stopping the system. The vast...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2009

    Migrating Protocols in Multi-Threaded Message-Passing Systems

    Dynamic software update is a technique by which a running program can be updated with new code and data without interrupting its execution. Often the authors will want to preserve properties of programs across update boundaries. Preserving simple typing across update boundaries for single-threaded programs is well studied. There are...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2009

    On Performance of Delegation in Java

    Delegation is an important design concept in object-oriented languages. In contrast to inheritance, which relates classes to each other, delegation operates on the level of objects and thus provides more flexibility. It is well known, that usage of delegation imposes performance penalties in the sense of delayed execution. But delegation...

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  • White Papers // Oct 2009

    Dynamic Software Updates for Real-Time Systems

    Seamlessly updating software in running systems has recently gained momentum. Dynamically updating the software of real-time embedded systems, however, still poses numerous challenges: such systems must meet hard deadlines, cope with limited resources, and adhere to high safety standards. This paper presents a solution for updating component-based cyclic embedded systems...

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  • White Papers // Apr 2010

    A Conceptual Model of Self-Monitoring Multi-Core Systems

    The paper discusses a conceptual model of building a self monitoring mechanism in a multi-core system such that the health of the entire system can be monitored securely and in an implicit manner. Accordingly, a many-core system is vertically partitioned (from hardware to application level) so that a small set...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2009

    Curatorial Work and Learning in Virtual Environments: A Virtual World Project to Support the NDIIPP Community

    The University of North Carolina at Chapel Hill and Virginia Tech (VPI&SU) are researching support of the digital preservation and curation community in Second Life (SL). The authors will explore how SL can be used, with a focus on education and dissemination. The assessment will ascertain how serious use of...

    Provided By Association for Computing Machinery

  • White Papers // Jan 2009

    Opportunities and Limits of Remote Timing Attacks

    Many algorithms can take a variable amount of time to complete depending on the data being processed. These timing differences can sometimes disclose confidential information. Indeed, researchers have been able to reconstruct an RSA private key purely by querying an SSL Web server and timing the results. The work analyzes...

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  • White Papers // Jul 2010

    XCo: Explicit Coordination to Prevent Network Fabric Congestion in Cloud Computing Cluster Platforms

    Large cluster-based cloud computing platforms increasingly use commodity Ethernet technologies, such as Gigabit Ethernet, 10GigE, and Fibre Channel over Ethernet (FCoE), for intra-cluster communication. Traffic congestion can become a performance concern in the Ethernet due to consolidation of data, storage, and control traffic over a common layer-2 fabric, as well...

    Provided By Association for Computing Machinery

  • White Papers // Sep 2010

    Would a "Cyber Warrior" Protect Us? Exploring Trade-Offs Between Attack and Defense of Information Systems

    As information security shifts from the realm of computer science to national security, the priority for safe and secure systems will be balanced against the appeal of using information insecurity as a strategic asset. In "Cyber war", those tasked with defending friendly computer networks are also expected to exploit enemy...

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  • White Papers // Sep 2009

    Designing Energy Efficient Automatic Repeat Request Protocol in Wireless Sensor Networks

    Energy constrained Wireless Sensor Networks (WSNs) challenge traditional protocols in many aspects. One such challenge is the requirement of energy efficiency in the Automatic Repeat Request (ARQ) protocols. Although traditional ARQ protocols are optimized for a better throughput, they fail to minimize the energy consumption. In some applications in sensor...

    Provided By Association for Computing Machinery

  • White Papers // Jul 2010

    Activity Recognition Using Cell Phone Accelerometers

    Mobile devices are becoming increasingly sophisticated and the latest generation of smart cell phones now incorporates many diverse and powerful sensors. These sensors include GPS sensors, vision sensors (i.e., Cameras), audio sensors (i.e., Microphones), light sensors, temperature sensors, direction sensors (i.e., Magnetic compasses), and acceleration sensors (i.e., Accelerometers). The availability...

    Provided By Association for Computing Machinery

  • White Papers // Dec 2010

    Spam Mitigation Using Spatio-Temporal Reputations From Blacklist History

    IP blacklists are a spam filtering tool employed by a large number of email providers. Centrally maintained and well regarded, blacklists can filter 80+% of spam without having to perform computationally expensive content-based filtering. However, spammers can vary which hosts send spam (Often in intelligent ways), and as a result,...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2010

    NeuroPhone: Brain-Mobile Phone Interface Using a Wireless EEG Headset

    Neural signals are everywhere just like mobile phones. The authors propose to use neural signals to control mobile phones for hands-free, silent and effortless human-mobile interaction. Until recently, devices for detecting neural signals have been costly, bulky and fragile. This paper presents the design, implementation and evaluation of the NeuroPhone...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2009

    SoundSense: Scalable Sound Sensing for People-Centric Applications on Mobile Phones

    Top end mobile phones include a number of specialized (e.g., Accelerometer, compass, GPS) and general purpose sensors (e.g., Microphone, camera) that enable new people-centric sensing applications. Perhaps the most ubiquitous and unexploited sensor on mobile phones is the microphone - a powerful sensor that is capable of making sophisticated inferences...

    Provided By Association for Computing Machinery

  • White Papers // Sep 2009

    A Geo-Location Based Opportunistic Data Dissemination Approach for MANETs

    In mobile scenarios, location dependent data can be provided by an infrastructure, or, in case an infrastructure is not available or feasible, by opportunistic networking among mobile devices populating the region of interest. Caused by node mobility, data availability within the region of interest relies on replication and forwarding techniques....

    Provided By Association for Computing Machinery

  • White Papers // Mar 2010

    Relational Cloud: The Case for a Database Service

    This paper makes the case for "Databases as a Service" (DaaS), with two target scenarios in mind: consolidation of data management functionality for large organizations and outsourcing data management to a cloud-based service provider for small/medium organizations. The authors analyze the many challenges to be faced, and discuss the design...

    Provided By Association for Computing Machinery

  • White Papers // Feb 2010

    An Operating System for Multicore and Clouds: Mechanisms and Implementation

    Cloud computers and multicore processors are two emerging classes of computational hardware that have the potential to provide unprecedented compute capacity to the average user. In order for the user to effectively harness all of this computational power, Operating Systems (OSes) for these new hardware platforms are needed. Existing multicore...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2011

    Blink: Managing Server Clusters on Intermittent Power

    Reducing the energy footprint of data centers continues to receive significant attention due to both its financial and environmental impact. There are numerous methods that limit the impact of both factors, such as expanding the use of renewable energy or participating in automated demand-response programs. To take advantage of these...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2010

    Private Memoirs of a Smart Meter

    Household smart meters that measure power consumption in real-time at fine granularities are the foundation of a future smart electricity grid. However, the widespread deployment of smart meters has serious privacy implications since they inadvertently leak detailed information about household activities. In this paper, the authors show that even without...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2011

    CloudNet: Dynamic Pooling of Cloud Resources by Live WAN Migration of Virtual Machines

    Virtual Machine technology and the ease with which VMs can be migrated within the LAN, has changed the scope of resource management from allocating resources on a single server to manipulating pools of resources within a data center. The authors expect WAN migration of virtual machines to likewise transform the...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2010

    Shipping to Streaming: Is This Shift Green?

    Streaming movies over the Internet has become increasingly popular in recent years as an alternative to mailing DVDs to a customer. In this paper the authors investigate the environmental- and energy-related impacts of these two methods of movie content delivery. They compare the total energy consumed and the carbon footprint...

    Provided By Association for Computing Machinery

  • White Papers // Feb 2010

    Empirical Evaluation of Latency-Sensitive Application Performance in the Cloud

    Cloud computing platforms enable users to rent computing and storage resources on-demand to run their networked applications and employ virtualization to multiplex virtual servers belonging to different customers on a shared set of servers. In this paper, the authors empirically evaluate the efficacy of cloud platforms for running latency-sensitive multimedia...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2009

    Online Piece-Wise Linear Approximation of Numerical Streams With Precision Guarantees

    Continuous "Always-on" monitoring is beneficial for a number of applications, but potentially imposes a high load in terms of communication, storage and power consumption when a large number of variables need to be monitored. The authors introduce two new filtering techniques, swing filters and slide filters, that represent within a...

    Provided By Association for Computing Machinery

  • White Papers // Feb 2011

    ZZ and the Art of Practical BFT Execution

    The high replication cost of Byzantine Fault-Tolerance (BFT) methods has been a major barrier to their widespread adoption in commercial distributed applications. The authors present ZZ, a new approach that reduces the replication cost of BFT services from 2f +1 to practically f +1. The key insight in ZZ is...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2009

    A Privacy Framework for Mobile Health and Home-Care Systems

    In this paper, the authors consider the challenge of preserving patient privacy in the context of mobile healthcare and home-care systems, that is, the use of mobile computing and communications technologies in the delivery of healthcare or the provision of at-home medical care and assisted living. This paper makes three...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2010

    Cryptographic Role-Based Security Mechanisms Based on Role-Key Hierarchy

    Even though Role-Based Access Control (RBAC) can tremendously help one minimize the complexity in administering users, it is still needed to realize the notion of roles at the resource level. In this paper, the authors propose a practical cryptographic RBAC model, called role-key hierarchy model, to support various security features...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2010

    FAME: A Firewall Anomaly Management Environment

    Firewalls are a widely deployed security mechanism to ensure the security of private networks in most businesses and institutions. The effectiveness of security protection provided by a firewall mainly depends on the quality of policy configured in the firewall. However, designing and managing firewall policies are often error-prone due to...

    Provided By Association for Computing Machinery

  • White Papers // Jan 2011

    ROARS: A Scalable Repository for Data Intensive Scientific Computing

    As scientific research becomes more data intensive, there is an increasing need for scalable, reliable, and high performance storage systems. Such data repositories must provide both data archival services and rich metadata, and cleanly integrate with large scale computing resources. ROARS is a hybrid approach to distributed storage that provides...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2010

    To Upgrade or Not to Upgrade

    Online software upgrades are often plagued by runtime behaviors that are poorly understood and difficult to ascertain. For example, the interactions among multiple versions of the software expose the system to race conditions that can introduce latent errors or data corruption. Moreover, industry trends suggest that online upgrades are currently...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2010

    Sonifying Performance Data to Facilitate Tuning of Complex Systems

    In the modern computing landscape, the challenge of tuning software systems is exacerbated by the necessity to accommodate multiple divergent execution environments and stakeholders. Achieving optimal performance requires a different configuration for every combination of hardware setups and business requirements. In addition, the state of the art in system tuning...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2010

    Unifying UPC and MPI Runtimes: Experience With MVAPICH

    Unified Parallel C (UPC) is an emerging parallel programming language that is based on a shared memory paradigm. MPI has been a widely ported and dominant parallel programming model for the past couple of decades. Real-life scientific applications require a lot of investment by domain scientists. Many scientists choose the...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2010

    Quantifying Performance Benefits of Overlap Using MPI-2 in a Seismic Modeling Application

    AWM-Olsen is a widely used ground motion simulation code based on a parallel finite difference solution of the 3-D velocity-stress wave equation. This application runs on tens of thousands of cores and consumes several million CPU hours on the TeraGrid Clusters every year. A significant portion of its run-time (37%...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2009

    Improving Binary Classification on Text Problems Using Differential Word Features

    The authors describe an efficient technique to weigh word-based features in binary classification tasks and show that it significantly improves classification accuracy on a range of problems. The most common text classification approach uses a document's ngrams (words and short phrases) as its features and assigns feature values equal to...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2009

    Traditional Assignment Considered Harmful

    Data movement in nearly all modern imperative languages is based on a single primitive: traditional assignment. (With traditional assignment, data are moved between variables by copying.) Unfortunately, traditional assignment poses many known software engineering drawbacks with respect to efficiency for value types, and with respect to modular reasoning for reference...

    Provided By Association for Computing Machinery

  • White Papers // May 2010

    Class Properties for Security Review in an Object-Capability Subset of Java

    In designing code for security review, it is helpful to make it easy to characterize the properties of objects in a program. A sufficiently rich type system can help with this goal: programmers can document the properties of objects through annotations on their types, and an appropriately constructed static code...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2009

    Bit Vector Algorithms Enabling High-Speed and Memory-Efficient Firewall Blacklisting

    In a world of increasing Internet connectivity coupled with increasing computer security risks, security conscious network applications implementing blacklisting technology are becoming very prevalent because it provides the ability to prevent information exchange from known malicious sources. Current technology implementing blacklisting does so at the application level. However, there are...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2010

    Weaver: Integrating Distributed Computing Abstractions Into Scientific Workflows Using Python

    Weaver is a high-level framework that enables researchers to integrate distributed computing abstractions into their scientific workflows. Rather than develop a new workflow language, the authors built Weaver on top of the Python programming language. As such, Weaver takes advantage of users' familiarity with Python, minimizes barriers to adoption, and...

    Provided By Association for Computing Machinery