Association for Computing Machinery

Displaying 41-80 of 7121 results

  • White Papers // Apr 2014

    Using Restricted Transactional Memory to Build a Scalable In-Memory Database

    The recent availability of Intel Haswell processors marks the transition of hardware transactional memory from research toys to mainstream reality. DBX is an in-memory database that uses Intel's Restricted Transactional Memory (RTM) to achieve high performance and good scalability across multicore machines. The main limitation (and also key to practicality)...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Snapshots in a Flash with ioSnap

    Snapshots are a common and heavily relied upon feature in storage systems. The high performance of flash-based storage systems brings new, more stringent, requirements for this classic capability. The author's present ioSnap, a flash optimized snapshot system. Through careful design exploiting common snapshot usage patterns and flash oriented optimizations, including...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Aerie: Flexible File-System Interfaces to Storage-Class Memory

    Storage-class memory technologies such as phase-change memory and memristors present a radically different interface to storage than existing block devices. As a result, they provide a unique opportunity to re-examine storage architectures. The authors find that the existing kernel-based stack of components, well suited for disks, unnecessarily limits the design...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Snapify: Capturing Snapshots of Offload Applications on Xeon Phi Manycore Processors

    Intel Xeon Phi coprocessors provide excellent performance acceleration for highly parallel applications and have been deployed in several top-ranking supercomputers. One popular approach of programming the Xeon Phi is the offload model, where parallel code is executed on the Xeon Phi, while the host system executes the sequential code. However,...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Excalibur: An Autonomic Cloud Architecture for Executing Parallel Applications

    IaaS providers often allow the users to specify many requirements for their applications. However, users without advanced technical knowledge usually do not provide a good specification of the cloud environment, leading to low performance and/or high monetary cost. In this context, the users face the challenges of how to scale...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Ariadne: Managing Fine-Grained Provenance on Data Streams

    Managing fine-grained provenance is a critical requirement for Data Stream Management Systems (DSMS), not only to address complex applications that require diagnostic capabilities and assurance, but also for providing advanced functionality such as revision processing or query debugging. This paper introduces a novel approach that uses operator instrumentation, i.e., modifying...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    A Hybrid Task Mapping Algorithm for Heterogeneous MPSoCs

    The application workloads in modern MPSoC-based embedded systems are becoming increasingly dynamic. Different applications concurrently execute and contend for resources in such systems, which could cause serious changes in the intensity and nature of the workload demands over time. To cope with the dynamism of application workloads at run time...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    GDM: Device Memory Management for GPGPU Computing

    GPGPUs are evolving from dedicated accelerators towards mainstream commodity computing resources. During the transition, the lack of system management of device memory space on GPGPUs has become a major hurdle. In existing GPGPU systems, device memory space is still managed explicitly by individual applications, which not only increases the burden...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    An Online Auction Framework for Dynamic Resource Provisioning in Cloud Computing

    Auction mechanisms have recently attracted substantial attention as an efficient approach to pricing and resource allocation in cloud computing. This work, to the authors' knowledge, represents the first online combinatorial auction designed in the cloud computing paradigm, which is general and expressive enough to both optimize system efficiency across the...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Scalable Performance Analysis of ExaScale MPI Programs through Signature-Based Clustering Algorithms

    Extreme-scale computing poses a number of challenges to application performance. Developers need to study application behavior by collecting detailed information with the help of tracing toolsets to determine shortcomings. But not only applications are \"Scalability challenged\", current tracing toolsets also fall short of exascale requirements for low back-ground overhead since...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    Mining Latent Entity Structures from Massive Unstructured and Interconnected Data

    The \"Big data\" era is characterized by an explosion of information in the form of digital data collections, ranging from scientific knowledge, to social media, news, and everyone's daily life. Examples of such collections include scientific publications, enterprise logs, news articles, social media and general web pages. Valuable knowledge about...

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  • White Papers // Apr 2014

    Major Technical Advancements in Apache Hive

    Apache Hive is a widely used data warehouse system for Apache Hadoop, and has been adopted by many organizations for various big data analytics applications. Closely working with many users and organizations, the authors have identified several shortcomings of Hive in its file formats, query planning, and query execution, which...

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  • White Papers // Apr 2014

    CGPA: Coarse-Grained Pipelined Accelerators

    High-Level Synthesis (HLS) tools dramatically reduce the nonrecurring engineering cost of creating specialized hardware accelerators. Existing HLS tools are successful in synthesizing efficient accelerators for program kernels with regular memory accesses and simple control flows. For other programs, however, these tools yield poor performance because they invoke computation units for...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2014

    PSelInv - A Distributed Memory Parallel Algorithm for Selected Inversion : the Symmetric Case

    The authors describe an efficient parallel implementation of the selected inversion algorithm for distributed memory computer systems, which they call PSelInv. The PSelInv method computes selected elements of a general sparse matrix A that can be decomposed as A = LU, where L is lower triangular and U is upper...

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  • White Papers // Apr 2014

    Palette: Enabling Scalable Analytics for Big-Memory, Multicore Machines

    Hadoop and its variants have been widely used for processing large scale analytics tasks in a cluster environment. However, use of a commodity cluster for analytics tasks needs to be reconsidered based on two key observations: in recent years, large memory, multicore machines have become more affordable; and recent studies...

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  • White Papers // Mar 2014

    Maple: Scalable Multi-Dimensional Range Search over Encrypted Cloud Data with Tree-based Index

    Cloud computing promises users massive scale outsourced data storage services with much lower costs than traditional methods. However, privacy concerns compel sensitive data to be stored on the cloud server in an encrypted form. This papers a great challenge for effectively utilizing cloud data, such as executing common SQL queries....

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  • White Papers // Mar 2014

    A Probabilistic Model for Linking Named Entities in Web Text with Heterogeneous Information Networks

    Heterogeneous information networks that consist of multi-type, interconnected objects are becoming ubiquitous and increasingly popular, such as social media networks and bibliographic networks. The task to link named entity mentions detected from the unstructured Web text with their corresponding entities existing in a heterogeneous information network is of practical importance...

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  • White Papers // Mar 2014

    Model Selection for Semi-Supervised Clustering

    Although there is a large and growing literature that tackles the semi-supervised clustering problem (i.e., using some labeled objects or cluster-guiding constraints like \"Must-link\" or \"Cannot-link\"), the evaluation of semi-supervised clustering approaches has rarely been discussed. The application of cross-validation techniques, for example, is far from straightforward in the semi-supervised...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Understanding, Modelling, and Improving the Performance of Web Applications in Multicore Virtualised Environments

    As the computing industry enters the cloud era, multicore architectures and virtualization technologies are replacing traditional IT infrastructures. However, the complex relationship between applications and system resources in multi-core virtualized environments is not well understood. Work-loads such as web services and online financial applications have the requirement of high performance...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Stochastic Computation

    Stochastic computation, as presented in this paper, exploits the statistical nature of application-level performance metrics, and matches it to the statistical attributes of the underlying device and circuit fabrics. Nanoscale circuit fabrics are viewed as noisy communication channels/networks. Communications-inspired design techniques based on estimation and detection theory are proposed. Stochastic...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Host-Compiled Multi-Core System Simulation for Early Real-Time Performance Evaluation

    With increasing complexity and software content, modern embedded platforms employ a heterogeneous mix of multi-core processors along with hardware accelerators in order to provide high performance in limited power budgets. To evaluate real-time performance and other constraints, full-system simulations are essential. With traditional approaches being either slow or inaccurate, so-called...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Evaluating Storage Systems for Scientific Data in the Cloud

    Infrastructure-as-a-Service (IaaS) clouds are an appealing resource for scientific computing. However, the bare-bones presentation of raw Linux virtual machines leaves much to the application developer. For many cloud applications, effective data handling is critical to efficient application execution. This paper investigates the capabilities of a variety of POSIX-accessible distributed storage...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Q100: The Architecture and Design of a Database Processing Unit

    In this paper, the authors propose Database Processing Units, or DPUs, a class of domain-specific database processors that can efficiently handle database applications. As a proof of concept, they present the instruction set architecture, microarchitecture, and hardware implementation of one DPU, called Q100. The Q100 has a collection of heterogeneous...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    The Benefit of SMT in the Multi-Core Era: Flexibility Towards Degrees of Thread-Level Parallelism

    The number of active threads in a multi-core processor varies over time and is often much smaller than the number of supported hardware threads. This requires multi-core chip designs to balance core count and per-core performance. Low active thread counts benefit from a few big, high-performance cores, while high active...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Locality-Oblivious Cache Organization Leveraging Single-Cycle Multi-Hop NoCs

    Locality has always been a critical factor in on-chip data placement on Chip Multi-Processors (CMPs) as accessing further-away caches has in the past been more costly than accessing nearby ones. Substantial research on locality-aware designs have thus focused on keeping a copy of the data private. However, this complicates the...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Guardrail: A High Fidelity Approach to Protecting Hardware Devices from Buggy Drivers

    While device driver code is both critical to proper system operation and more susceptible to bugs than other system software, relatively little work has been done in the area of online driver correctness monitoring (perhaps due to the performance-sensitive nature of driver software). This paper demonstrate that decoupled correctness checking...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    I/O Paravirtualization at the Device File Boundary

    Paravirtualization is an important I/O virtualization technology since it uniquely provides all of the following benefits: the ability to share the device between multiple VMs, support for legacy devices without virtualization hardware, and high performance. However, existing paravirtualization solutions have one main limitation: they only support one I/O device class,...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    REF: Resource Elasticity Fairness with Sharing Incentives for Multiprocessors

    With the democratization of cloud and datacenter computing, users increasingly share large hardware platforms. In this setting, architects encounter two challenges: sharing fairly and sharing multiple resources. Drawing on economic game-theory, the authors rethink fairness in computer architecture. A fair allocation must provide Sharing Incentives (SI), Envy-Freeness (EF), and Pareto...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Heterogeneous-race-free Memory Models

    Commodity heterogeneous systems (e.g., integrated CPUs and GPUs), now support a unified, shared memory address space for all components. Because the latency of global communication in a heterogeneous system can be prohibitively high, heterogeneous systems (unlike homogeneous CPU systems) provide synchronization mechanisms that only guarantee ordering among a subset of...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Price Theory Based Power Management for Heterogeneous Multi-Cores

    Heterogeneous multi-cores that integrate cores with different power-performance characteristics are promising alternatives to homogeneous systems in energy- and thermally constrained environments. However, the heterogeneity imposes significant challenges to power-aware scheduling. The authors present a price theory-based dynamic power management framework for heterogeneous multi-cores that co-ordinates various energy savings opportunities, such...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Scale-Out NUMA

    Emerging datacenter applications operate on vast datasets that are kept in DRAM to minimize latency. The large number of servers needed to accommodate this massive memory footprint requires frequent server-to-server communication in applications such as key-value stores and graph-based applications that rely on large irregular data structures. The fine-grained nature...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Integrated 3D-Stacked Server Designs for Increasing Physical Density of Key-Value Stores

    Key-value stores, such as Memcached, have been used to scale web services since the beginning of the Web 2.0 era. Data center real estate is expensive, and several industry experts the authors have spoken to have suggested that a significant portion of their data center space is devoted to key-value...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Rhythm: Harnessing Data Parallel Hardware for Server Workloads

    Trends in increasing web traffic demand an increase in server throughput while preserving energy efficiency and total cost of ownership. Present work in optimizing data center efficiency primarily focuses on the data center as a whole, using off-the-shelf hardware for individual servers. Server capacity is typically increased by adding more...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Sapper: A Language for Hardware-Level Security Policy Enforcement

    Privacy and integrity are important security concerns. These concerns are addressed by controlling information flow, i.e., restricting how information can flow through a system. Most proposed systems that restrict information flow make the implicit assumption that the hardware used by the system is fully \"Correct\" and that the hardware's instruction...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    K2: A Mobile Operating System for Heterogeneous Coherence Domains

    Mobile System-on-Chips (SoC) that incorporate heterogeneous coherence domains promise high energy efficiency to a wide range of mobile applications, yet are difficult to program. To exploit the architecture, a desirable, yet missing capability is to replicate Operating System (OS) services over multiple coherence domains with minimum inter-domain communication. In designing...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    A Virtualized Separation Kernel for Mixed Criticality Systems

    Multi- and many-core processors are becoming increasingly popular in embedded systems. Many of these processors now feature hardware virtualization capabilities, such as the ARM Cortex A15, and x86 processors with Intel VT-x or AMD-V support. Hardware virtualization offers opportunities to partition physical resources, including processor cores, memory and I/O devices...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    Shrinking the Hypervisor One Subsystem at a Time

    Efficient and secure networking between virtual machines is crucial in a time where a large share of the services on the Internet and in private datacenters run in virtual machines. To achieve this efficiency, virtualization solutions, such as Qemu/KVM, move towards a monolithic system architecture in which all performance critical...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    iACT: A Software-Hardware Framework for Understanding the Scope of Approximate Computing

    Approximate computing has recently emerged as a paradigm for enabling energy efficient software and hardware implementations by exploiting the inherent resiliency in applications to impreciseness in their underlying computations. Much of the previous work in this area has demonstrated the potential for significant energy and performance improvements, but these works...

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  • White Papers // Mar 2014

    Application-Aware Memory System for Fair and Efficient Execution of Concurrent GPGPU Applications

    The available computing resources in modern GPUs are growing with each new generation. However, as many general purpose applications with limited thread-scalability are tuned to take advantage of GPUs, available compute resources might not be optimally utilized. To address this, modern GPUs will need to execute multiple kernels simultaneously. As...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2014

    A CPU-GPU Hybrid Implementation and Model-Driven Scheduling of the Fast Multipole Method

    This paper presents an optimized CPU-GPU hybrid implementation and a GPU performance model for the kernel-independent Fast Multipole Method (FMM). The authors implement an optimized kernel-independent FMM for GPUs, and combine it with their previous CPU implementation to create a hybrid CPU+GPU FMM kernel. When compared to another highly optimized...

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  • White Papers // Aug 2011

    Dasu - ISP Characterization from the Edge: A BitTorrent Implementation

    Evaluating and characterizing access ISPs is critical to consumers shopping for alternative services and governments surveying the availability of broadband services to their citizens. The authors present Dasu, a service for crowdsourcing ISP characterization to the edge of the network. Dasu is implemented as an extension to a popular BitTorrent...

    Provided By Association for Computing Machinery

  • White Papers // Sep 2010

    Crowdsourcing Service-Level Network Event Monitoring

    The user experience for networked applications is becoming a key benchmark for customers and network providers. Perceived user experience is largely determined by the frequency, duration and severity of network events that impact a service. While today's networks implement sophisticated infrastructure that issues alarms for most failures, there remains a...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    On Pending Interest Table in Named Data Networking

    Internet has witnessed its paramount function transition from host-to-host communication to content dissemination. Named Data Net-working (NDN) and Content-Centric Networking (CCN) emerge as a clean slate network architecture to embrace this shift. Pending Interest Table (PIT) in NDN/CCN keeps track of the Interest packets that are received but yet un-responded,...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2011

    Experiences Using Cloud Computing for a Scientific Workflow Application

    Clouds are rapidly becoming an important platform for scientific applications. In this paper, the authors describe their experiences running a scientific workflow application in the cloud. The application was developed to process astronomy data released by the Kepler project, a NASA mission to search for Earth-like planets orbiting other stars....

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    CloudFilter: Practical Control of Sensitive Data Propagation to the Cloud

    A major obstacle for the adoption of cloud services in enterprises is the potential loss of control over sensitive data. Companies often have to safeguard a subset of their data because it is crucial to their business or they are required to do so by law. In contrast, cloud service...

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  • White Papers // Feb 2012

    Algorithm-Based Fault Tolerance for Dense Matrix Factorizations

    Dense matrix factorizations, such as LU, Cholesky and QR, are widely used for scientific applications that require solving systems of linear equations, eigenvalues and linear least squares problems. Such computations are normally carried out on supercomputers, whose ever-growing scale induces a fast decline of the Mean Time To Failure (MTTF)....

    Provided By Association for Computing Machinery

  • White Papers // Aug 2012

    CluChunk: Clustering Large Scale User-Generated Content Incorporating Chunklet Information

    The exponential rise of online content in the form of blogs, microblogs, forums, and multimedia sharing sites has raised an urgent demand for efficient and high-quality text clustering algorithms for fast navigation and browsing of users based on better document organization. For several kinds of this user-generated content, it is...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2012

    User-Interest Based Community Extraction in Social Networks

    The rapid evolution of modern social networks motivates the design of networks based on users' interests. Using popular social media such as Facebook and Twitter, the authors show that this new perspective can generate more meaningful information about the networks. In this paper, they model user-interest based networks by deducing...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2012

    Crowdsourcing Recommendations From Social Sentiment

    In this paper, the authors investigate an innovative recommendation system by incorporating relevant social opinion and sentiment information. Their recommendation system, a powerful application of social sentiment analysis, differs from many existing models, which investigate the situation where the social network itself is structured to work with the product ranking...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    Sentiment Identification by Incorporating Syntax, Semantics and Context Information

    Understanding the sentiment of sentences allows users to summarize opinions which could help people make informed decisions. All of the state-of-the-art algorithms perform well on individual sentences without considering any context in-formation, but their accuracy is dramatically lower on the document level because they fail to consider context and the...

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  • White Papers // Mar 2010

    FANGS: High Speed Sequence Mapping for Next Generation Sequencers

    Next Generation Sequencing machines are generating millions of short DNA sequences (reads) everyday. There is a need for efficient algorithms to map these sequences to the reference genome to identify SNPs or rare transcripts and to fulfill the dream of personalized medicine. The authors present a Fast Algorithm for Next...

    Provided By Association for Computing Machinery

  • White Papers // Apr 2010

    The New Frontier of Communications Research: Smart Grid and Smart Metering

    This paper discusses some of the challenges and opportunities of communications research in the area of smart grids and smart metering. It is clear that the communications research community has been actively seeking the 'Next big thing' after interests in recent hot topics such as cognitive radio, cooperative communications, and...

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  • White Papers // Jun 2011

    Smart Data Structures: An Online Machine Learning Approach to Multicore Data Structures

    As multicores become prevalent, the complexity of programming is skyrocketing. One major difficulty is efficiently orchestrating collaboration among threads through shared data structures. Unfortunately, choosing and hand-tuning data structure algorithms to get good performance across a variety of machines and inputs is a herculean task to add to the fundamental...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2012

    Can You GET Me Now? Estimating the Time-to-First-Byte of HTTP Transactions With Passive Measurements

    Cellular network operators have a compelling interest to monitor HTTP transaction latency because it is an important component of the user experience. Existing techniques to monitor latency require active probing or use passive analysis to estimate Round-Trip Time (RTT). Unfortunately, it is impractical to use active probing to monitor entire...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2012

    Obtaining In-Context Measurements of Cellular Network Performance

    Network service providers, and other parties, require an accurate understanding of the performance cellular networks deliver to users. In particular, they often seek a measure of the network performance users experience solely when they are interacting with their device - a measure the authors call in-context. Acquiring such measures is...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2012

    A First Look at Cellular Machine-to-Machine Traffic - Large Scale Measurement and Characterization

    Cellular network based Machine-To-Machine (M2M) communication is fast becoming a market-changing force for a wide spectrum of businesses and applications such as telematics, smart metering, point-of-sale terminals, and home security and automation systems. In this paper, the authors aim to answer the following important question: Does traffic generated by M2M...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2012

    Performance Evaluation of DTN Implementations on a Large-Scale Network Emulation Testbed

    In this paper, the authors present a series of experiments that evaluate the performance of two DTN implementations, DTN2 and IBR-DTN, in urban mobility scenarios. The experiments were carried out on the wireless network emulation test-bed named QOMB, which was extended to support such DTN evaluations. Their quantitative assessment verified...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2012

    Making the Best of Two Worlds: A Framework for Hybrid Experiments

    In this paper, the authors present the design and implementation of a framework for hybrid experiments that integrates a real-world wireless testbed with a wireless network emulation testbed. The real-world component of the framework, that they call physical realm, can be used for those experiment aspects that are difficult to...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2011

    Fault Injection on a Large-Scale Network Testbed

    In the real Internet, various types of problems are encountered. Before integrating new technologies into the Internet, developers should understand the behavior of these technologies in the event of fault occurrence. Researchers conduct experiments on network testbeds to evaluate new technologies, but the main focus of the evaluations done so...

    Provided By Association for Computing Machinery

  • White Papers // May 2012

    Energy Harvesting Enabled Wireless Sensor Networks: Energy Model and Battery Dimensioning

    Wireless Sensor Networks (WSN) present a pending challenge for a complete deployability due to energy requirements. The Self-Powered WSN approach aims to extend the sensor node life by means of Energy Harvesting. However, the low power density that these energy sources provide compared to the required energy for the communication...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    Changing of the Guards: A Framework for Understanding and Improving Entry Guard Selection in Tor

    Tor is the most popular low-latency anonymity overlay network for the Internet, protecting the privacy of hundreds of thousands of people every day. To ensure a high level of security against certain attacks, Tor currently utilizes special nodes called entry guards as each client's long-term entry point into the anonymity...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    Enhancing Tor's Performance Using Real-Time Traffic Classification

    Tor is a low-latency anonymity-preserving network that enables its users to protect their privacy online. It consists of volunteer-operated routers from all around the world that serve hundreds of thousands of users every day. Due to congestion and a low relay-to-client ratio, Tor suffers from performance issues that can potentially...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2009

    SniffMob: Inferring Human Contact Patterns Using Wireless Devices

    The size of existing data sets regarding human mobility and person-to-person contact has been limited by the labor-intensive nature of the data collection techniques employed. In this paper, the authors propose a practical data collection system which is automatic and transparent to the user, requires only installing new software, and...

    Provided By Association for Computing Machinery

  • White Papers // Nov 2012

    Low-Power Wireless Bus

    The authors present the Low-Power Wireless Bus (LWB), a communication protocol that supports several traffic patterns and mobile nodes immersed in static infrastructures. LWB turns a multi-hop low-power wireless network into an infrastructure similar to a shared bus, where all nodes are potential receivers of all data. It achieves this...

    Provided By Association for Computing Machinery

  • White Papers // Jan 2013

    NBTI-Aware Design of NoC Buffers

    Network-on-Chips (NoC) play a central role in determining performance and reliability in current and future multi-core architectures. Continuous scaling of CMOS technology enable widespread adoption of multi-core architectures but, unfortunately, poses severe concerns regarding failures. Process Variation (PV) is worsening the scenario, decreasing device lifetime and performance predictability during chip...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    Enabling Ultra-Low Power Operation in High-End Wireless Sensor Networks Nodes

    This paper presents a prototype hardware/software architecture for minimizing energy consumption on high-end microcontrollers, while simplifying the development of applications providing a general-purpose-like programming environment. The key features enabling this twofold goal are operating system support to processes, optimized sensing and hibernation of the system state. To balance performance offered...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    Software Energy Optimization Through Fine-Grained Function-Level Voltage and Frequency Scaling

    This paper presents a methodology and a tool-chain to perform estimation and optimization of the energy consumption associated to software execution on tiny embedded systems. The estimation phase is based on an ISA-level characterization of the target processor, while the optimization phase is made combining the estimation process with design...

    Provided By Association for Computing Machinery

  • White Papers // Oct 2012

    Effective Service Capacity Analysis of Opportunistic Multi-Carrier OFDMA Systems

    Exact queuing-theoretic modeling of wireless systems is tough due to the complex service processes that arise from the interaction of the wireless channel with state-of-the-art signal processing algorithms. Nevertheless, with the rise of video applications like streaming and telephony in upcoming fourth generation cellular networks, such analysis is important for...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2011

    Runtime Efficient Event Scheduling in Multi-Threaded Network Simulation

    Developing an efficient parallel simulation framework for multiprocessor systems is hard. A primary concern is the considerable amount of parallelization overhead imposed on the event handling routines of the simulator. Besides complex event scheduling algorithms, the main sources of overhead are thread synchronization and locking of shared data. Thus, compared...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2012

    Choice as a Principle in Network Architecture

    There has been a great interest in defining a new network architecture that can meet the needs of a future Internet. One of the main challenges in this context is how to realize the many different technical solutions that have developed in recent years in a single coherent architecture. In...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2009

    DIRC: Increasing Indoor Wireless Capacity Using Directional Antennas

    The demand for wireless bandwidth in indoor environments such as homes and offices continues to increase rapidly. Although, wireless technologies such as MIMO can reach link throughputs of 100s of Mbps (802.11n) for a single link, the question of how the authors can deliver high throughput to a large number...

    Provided By Association for Computing Machinery

  • White Papers // Sep 2012

    Dynamic Energy-Aware Capacity Provisioning for Cloud Computing Environments

    Data centers have recently gained significant popularity as a cost-effective platform for hosting large-scale service applications. While large data centers enjoy economies of scale by amortizing initial capital investment over large number of machines, they also incur tremendous energy cost in terms of power distribution and cooling. An effective approach...

    Provided By Association for Computing Machinery

  • White Papers // Feb 2013

    Reusable Requirements in Automated Verification of Distributed Systems

    The growing popularity of infrastructure-as-a-service cloud computing, software-defined networking, and related technologies have enabled the rapid creation of complex, large-scale distributed systems. Many of these systems are used by applications with stricter requirements than those covered by SLAs, such as those used by the financial, healthcare, and industrial sectors. Mathematical...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2009

    A Unified Metric for Quality of Service Quantification

    Internet service providers usually express the quality of network services through a set of values determined according to several network performance parameters periodically collected or measured. However, for common end-users, these values do not give an overall idea of the quality of the network services as they stand for different...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2010

    Simulating Large-Scale Dynamic Random Graphs in OMNeT++

    Simulating large-scale dynamic systems becomes increasingly more important as real-world systems grow in scale. The authors present a set of components for the OMNeT++ discrete event simulator which enable efficient modeling of large-scale random graphs that capture real-world properties, e.g. scale-free networks and small-world topologies. The complexities of the network...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2009

    Scaling the Bandwidth Wall: Challenges in and Avenues for CMP Scaling

    As transistor density continues to grow at an exponential rate in accordance to Moore's law, the goal for many Chip Multi-Processor (CMP) systems is to scale the number of on-chip cores proportionally. Unfortunately, off-chip memory bandwidth capacity is projected to grow slowly com-pared to the desired growth in the number...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2009

    MemTracker: An Accelerator for Memory Debugging and Monitoring

    Memory bugs are a broad class of bugs that is becoming increasingly common with increasing software complexity, and many of these bugs are also security vulnerabilities. Existing software and hardware approaches for finding and identifying memory bugs have a number of drawbacks including considerable performance overheads, target only a specific...

    Provided By Association for Computing Machinery

  • White Papers // Jun 2012

    Low-Complexity Scheduling for Wireless Networks

    Designing efficient scheduling and power control algorithms for distributed wireless communication has been a challenging issue, especially in the physical interference model based on SINR constraints. In this paper, the authors discuss the first local distributed scheduling and power control algorithm in the SINR-model that achieves an O(g(L)) approximation factor...

    Provided By Association for Computing Machinery

  • White Papers // Aug 2011

    Video Streaming Using a Location-Based Bandwidth-Lookup Service for Bitrate Planning

    In this paper, the authors describe a video streaming system for receivers equipped with a GPS. A receiver's download rate is constantly monitored, and periodically reported back to a central database along with associated GPS positional data. Thus, based on the current location, a streaming device can use a GPS-based...

    Provided By Association for Computing Machinery

  • White Papers // Mar 2013

    Commute Path Bandwidth Traces from 3G Networks: Analysis and Applications

    In this dataset paper, the authors present and make available real-world measurements of the throughput that was achieved at the application layer when adaptive HTTP streaming was performed over 3G networks using mobile devices. For the streaming sessions, they used popular commute routes in and around Oslo (Norway) traveling with...

    Provided By Association for Computing Machinery