Washington University in St. Louis

Displaying 1-40 of 96 results

  • White Papers // Oct 2011

    Near Optimal Rate Selection for Wireless Control Systems

    With the advent of industrial standards such as WirelessHART, recently there has been success in real-world deployment of wireless control systems in process industries. Due to limited bandwidth in Wireless Sensor-Actuator Networks (WSANs), it is important to optimize the control performance subject to the network resource constraints of WSANs. In...

    Provided By Washington University in St. Louis

  • White Papers // Sep 2011

    Improved End-to-End Delay Analysis in WirelessHART Networks

    WirelessHART is a new standard specifically designed for real-time and reliable communication between sensor and actuator devices for industrial process monitoring and control applications. End-to-end communication delay analysis for WirelessHART networks is required for acceptance test of real-time data flows from sensors to actuators and for workload adjustment in response...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2011

    Distributed Channel Allocation Algorithms for Wireless Sensor Networks

    Interference between concurrent transmissions can cause severe performance degradation in Wireless Sensor Networks (WSNs). While multiple channels available in WSN technology such as IEEE 802.15.4 can be exploited to mitigate interference, channel allocation can have a significant impact on the performance of multi-channel communication. This paper proposes a set of...

    Provided By Washington University in St. Louis

  • White Papers // May 2011

    Multi-Core Real-Time Scheduling for Generalized Parallel Task Models

    Multi-core processors offer a significant performance increase over single core processors. Therefore, they have the potential to enable real-time applications that must complete large amounts of computation within stringent timing constraints that cannot be met on traditional single-core processors. However, most results in traditional multiprocessor real-time scheduling are limited to...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2011

    Spam or Ham? Characterizing and Detecting Fraudulent "Not Spam" Reports in Web Mail Systems

    Web mail providers rely on users to "Vote" to quickly and collaboratively identify spam messages. Unfortunately, spammers have begun to use large collections of compromised accounts not only to send spam, but also to vote "Not spam" on many spam emails in an attempt to thwart collaborative filtering. The authors...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2011

    Priority Assignment for Real-Time Flows in WirelessHART Networks

    WirelessHART is a new wireless sensor-actuator network standard specifically developed for process industries. A key challenge faced by WirelessHART networks is to meet the stringent real-time communication requirements imposed by process monitoring and control applications. Fixed-priority scheduling, a popular scheduling policy in real-time networks, has recently been shown to be...

    Provided By Washington University in St. Louis

  • White Papers // Mar 2011

    What's Intellectual Property Good For?

    Intellectual property may turn out to be among a handful of themes that will accompany us for most of the XXI century, shaping our economic future and maybe not just that. In spite of having been around - with ups and downs - since the times of James Watt, the...

    Provided By Washington University in St. Louis

  • White Papers // Feb 2011

    Multi-Tier Diversified Service Architecture for Internet 3.0: The Next Generation Internet

    The next generation Internet needs to support multiple diverse application contexts. In this paper, the authors present Internet 3.0, a diversified, multi-tier architecture for the next generation Internet. Unlike the current Internet, Internet 3.0 defines a new set of primitives that allows diverse applications to compose and optimize their specific...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Feedback Thermal Control of Real-Time Systems on Multicore Processors

    Real-time systems face significant challenges in thermal management with their adoption of modern multicore processors. While earlier research on feedback thermal control has shown promise in dealing with the uncertainties in the thermal characteristics, multicore processors introduce new challenges that cannot be handled by previous solutions designed for single-core processors....

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    ARCH: Practical Channel Hopping for Reliable Home-Area Sensor Networks

    Home Area Networks (HANs) promise to enable sophisticated home automation applications such as smart energy usage and assisted living. However, recent empirical study of HAN reliability in real-world residential environments revealed significant challenges to achieving reliable performance in the face of significant and variable interference from a multitude of coexisting...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Priority Assignment for Real-Time Flows in WirelessHART Sensor-Actuator Networks

    Recent years have witnessed the adoption of wireless sensor-actuator networks as a communication infrastructure for process control applications. An important enabling technology for industrial process control is WirelessHART, an open wireless sensor-actuator network standard specifically developed for process industries. A key challenge faced by WirelessHART networks is to meet the...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    End-to-End Delay Analysis for Fixed Priority Scheduling in WirelessHART Networks

    The WirelessHART standard has been specifically designed for real-time communication between sensor and actuator devices for industrial process monitoring and control. End-to end communication delay analysis for WirelessHART networks is required for acceptance test of real-time data flows from sensors to actuators and for workload adjustment in response to network...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Architectures for the Future Networks and the Next Generation Internet: A Survey

    The Internet has evolved from being an academic pursuit to a huge commercial commodity. The IP thin waist associated with the simplicity of the present design, has been a remarkable architectural choice, motivated by the need to converge multiple link layer technologies and end-to-end transport mechanisms. However, the assumptions under...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Fast Incremental CRC Updates for IP Over ATM Networks

    In response to the increasing network speeds, many operations in IP routers and similar devices are being made more efficient. With the advances in other areas of packet processing, the verification and regeneration of Cyclic Redundancy Check (CRC) codes of the data link layer is likely to become a bottleneck...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Design of a High Performance Dynamically Extensible Router

    This paper describes the design, implementation and performance of an open, high performance, dynamically extensible router under development at Washington University in St. Louis. This router supports the dynamic installation of software and hardware plugins in the data path of application data flows. It provides an experimental platform for research...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Greedy Geographic Routing Is Good Enough in Sensing Covered Networks

    This paper presents a theoretical analysis of greedy geographic routing protocols on a common class of wireless sensor networks that must provide sensing coverage over a geographic area. Contrary to well known results on random networks, the authors prove that the Greedy Geographic Forwarding and the new greedy protocol always...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Hierarchical Control of Multiple Resources in Distributed Real-Time and Embedded Systems

    There is an increasing demand to introduce adaptive capabilities in Distributed Real-time and Embedded (DRE) systems that execute in open environments where system operational conditions, input workload, and resource availability cannot be characterized accurately a priori. To meet these needs, this paper presents the Hierarchical Distributed Resource-management Architecture (HiDRA), which...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    FCS/nORB: A Feedback Control Real-Time Scheduling Service in Object Request Broker Middleware

    Object Request Broker (ORB) middleware has shown promise in meeting the functional and real-time performance requirements of Distributed Real-time and Embedded (DRE) systems. However, existing real-time ORB middleware standards such as RT-CORBA do not adequately address the challenges of providing robust performance guarantees portably across different platforms, and managing unpredictable...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Implementation of Network Application Layer Parser for Multiple TCP/IP Flows in Reconfigurable Devices

    This paper presents an implementation of a high-performance network application layer parser in FPGAs. At the core of the architecture resides a pattern matcher and a parser. The pattern matcher scans for patterns in high-speed streaming TCP data streams. The parser core augments each pattern found with semantic information determined...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Formal Specification and Design of Mobile Systems

    Termination detection, a classical problem in distributed computing, is revisited in the new setting provided by the emerging mobile computing technology. A simple solution tailored for use in ad hoc networks is employed as a vehicle for demonstrating the applicability of formal requirements and design strategies to the new field...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Credit Risk And IFRS: The Case Of Credit Default Swaps

    Theory predicts that the accounting information transparency affects credit spreads. Given that one of the putative benefits of International Financial Reporting Standards (IFRS) is transparency of accounting information; this paper evaluates the impact of IFRS on the pricing of credit spreads in the over-the-counter Credit Default Swap market. Where it...

    Provided By Washington University in St. Louis

  • White Papers // Nov 2010

    Strong Bubbles And Common Expected Bubbles In A Finite Horizon Model

    An expected bubble is said to exist if it is mutual knowledge that the price of the asset is higher than the expected dividend. Similarly we call it a strong bubble if everyone knows that the price is higher than the maximum possible dividend. Substituting common knowledge for mutual knowledge,...

    Provided By Washington University in St. Louis

  • White Papers // Nov 2010

    Infrastructure Arrangement for Application Virtualization Services

    This paper first briefly introduces the current development of application virtualization and the Internet usage trend. Implementing application virtualization technologies on mobile computing devices will bring both benefits and challenges. This paper proposes a distributed server arrangement with the corresponding hand-off protocol to provide smooth and responsive user experiences for...

    Provided By Washington University in St. Louis

  • White Papers // Oct 2010

    Optimal Design-Space Exploration of Streaming Applications

    Many embedded and scientific applications are frequently pipelined asynchronously and deployed on architecturally diverse systems to meet performance requirements and resource constraints. The authors call such pipelined applications streaming applications. Typically, there are several design parameters in the algorithms and architectures used that, when customized, impact the tradeoff between different...

    Provided By Washington University in St. Louis

  • White Papers // Oct 2010

    The Design and Implementation of MCFlow: A Real-Time Multi-Core Aware Middleware for Dependent Task Graphs

    Modern computer architectures have evolved from uniprocessor platforms to multi-processor and multi-core platforms, but traditional real-time distributed middleware such as RT-CORBA has not kept pace with that evolution. To address those issues, this paper describes the design and implementation of MCFlow, a new real-time distributed middleware for dependent task graphs...

    Provided By Washington University in St. Louis

  • White Papers // Sep 2010

    Real-Time Scheduling for WirelessHART Networks

    WirelessHART is an open wireless sensor-actuator network standard for industrial process monitoring and control that requires real-time data communication between sensor and actuator devices. Salient features of a WirelessHART network include a centralized network management architecture, multi-channel TDMA transmission, redundant routes, and avoidance of spatial reuse of channels for enhanced...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2010

    Multi-Channel Reliability and Spectrum Usage in Real Homes: Empirical Studies for Home-Area Sensor Networks

    Home Area Networks (HANs) consisting of wireless sensors have emerged as the enabling technology for important applications such as smart energy and assisted living. A key challenge faced by HANs is maintaining reliable operation in real-world residential environments. This paper presents two indepth empirical studies on the wireless channels in...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2010

    Better Languages for More Effective Designing

    Developer productivity is strongly influenced by the language(s) used during the design process. The abstraction level of the language as well as the opportunities for casual errors due to non-intuitive language features can both have a dramatic impact on developers. In this paper, the authors explore language design in three...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2010

    Distributed Algorithms for the Placement of Network Services

    Network services play an important role in the Internet today. They serve as data caches for websites, servers for multiplayer games and relay nodes for Voice over IP (VoIP) conversations. While much research has focused on the design of such services, little attention has been focused on their actual placement....

    Provided By Washington University in St. Louis

  • White Papers // Jun 2010

    Against All Probabilities: A Modeling Paradigm for Streaming Applications That Goes Against Common Notions

    Hardware and software design requires the right portion of skills and mental faculties. The design of a good system is an exercise in rational thinking, engineering, and art. The design process is further complicated when the authors aspire to build systems that exploit parallelism or are targeted to be deployed...

    Provided By Washington University in St. Louis

  • White Papers // Jun 2010

    Design of an Extensible Network Testbed

    Networking testbeds have become an increasingly important part of the networking research cycle. One of the primary reasons for this is that testbeds offer researchers access to network conditions and environments which are very difficult to reproduce in a local laboratory. This work presents the design of the Open Network...

    Provided By Washington University in St. Louis

  • White Papers // May 2010

    An Identifier/Locator Split Architecture for Exploring Path Diversity Through Site Multi-Homing - A Hybrid Host-Network Cooperative Approach

    In this paper, the authors take a fresh look at stub-site multi-homing within the paradigms of an identifier/locator split architecture. More specifically, they investigate the possibility of enabling multi-homed stub network sites to improve the performance of their end-to-end TCP flows by leveraging the path diversity of the underlying network....

    Provided By Washington University in St. Louis

  • White Papers // May 2010

    Sorting as a Streaming Application Executing on Chip Multiprocessors

    Expressing concurrency in applications has always been a difficult and error-prone endeavor, yet effective utilization of multi-core processors requires that the concurrency in applications be understood. One approach to the expression of concurrency is streaming, which has shown real promise as a safe and effective method for many application classes....

    Provided By Washington University in St. Louis

  • White Papers // May 2010

    Modeling and Resource Allocation for HD Videos Over WiMAX Broadband Wireless Networks

    Mobile video is considered a major upcoming application and revenue generator for broadband wireless networks like WiMAX and LTE. Therefore, it is important to design a proper resource allocation scheme for mobile video, since video traffic is both throughput consuming and delay sensitive. In order to compare resource allocation schemes...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2010

    Robust Sensor Networks in Homes Via Reactive Channel Hopping

    Home Area Networks (HANs) consisting of wireless sensors have emerged as the enabling technology for important applications such as smart energy and assisted living. A key challenge faced in deploying robust Wireless Sensor Networks (WSNs) for home automation applications is the need to provide long-term, reliable operation in the face...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2010

    Capacity Evaluation for IEEE 802.16e Mobile WiMAX

    This paper presents a simple analytical method for capacity evaluation of IEEE 802.16e Mobile WiMAXTM networks. Various overheads that impact the capacity are explained and methods to reduce these overheads are also presented. The advantage of a simple model is that the effect of each decision and sensitivity to various...

    Provided By Washington University in St. Louis

  • White Papers // Mar 2010

    Quality Ladders, Competition And Endogenous Growth

    The authors examine a theory of competitive innovation in which new ideas are introduced only when diminishing returns to the use of existing ideas sets in. After an idea is introduced, the knowledge capital associated with that idea expands, and its value falls. Once the value falls far enough, it...

    Provided By Washington University in St. Louis

  • White Papers // Mar 2010

    The Economic Effects Of SOX Section 404 Compliance: A Corporate Insider Perspective

    Based on survey responses from 3,138 corporate insiders, the authors analyze the costs and benefits of compliance with Section 404 of the Sarbanes-Oxley Act of 2002. The vast majority of respondents recognize at least some Section 404 compliance benefits, consistent with it being an effective governance mechanism. The evidence, however,...

    Provided By Washington University in St. Louis

  • White Papers // Feb 2010

    eOCSA: An Algorithm for Burst Mapping With Strict QoS Requirements in IEEE 802.16e Mobile WiMAX Networks

    Mobile WiMAX systems based on the IEEE 802.16e standard require all downlink allocations to be mapped to a rectangular region in the two dimensional subcarrier-time map. Many published resource allocation schemes ignore this requirement. It is possible that the allocations when mapped to rectangular regions may exceed the capacity of...

    Provided By Washington University in St. Louis

  • White Papers // Feb 2010

    Robust Control-Theoretic Thermal Balancing for Server Clusters

    Thermal management is critical for clusters because of the increasing power consumption of modern processors, compact server architectures and growing server density in data centers. Thermal balancing mitigates hot spots in a cluster through dynamic load distribution among servers. This paper presents two Control-theoretical Thermal Balancing (CTB) algorithms that dynamically...

    Provided By Washington University in St. Louis

  • White Papers // May 2009

    Cloud Computing Challenges and Related Security Issues

    The field of cloud computing is still in its infancy as far as implementation and usage, partly because it is heavily promoted by technology advancement and is so high resource dependent that researches in academic institutions have not had many opportunities to analyze and experiment with it. However, cloud computing...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2009

    Access Control Service Oriented Architecture Security

    Service-Oriented-Architecture (SOA) is one of the most popular concepts to implement computing systems. However it faces many challenges to security and many standards and frameworks come out to support it. It focuses especially on the access control system using SOA and represent what are the SAML and XACML and how...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2010

    Scalable High Speed IP Routing Lookups

    The Internet is becoming ubiquitous?everyone wants to be a part of it. Since the advent of the World Wide Web, the number of users, hosts, domains, and networks connected to the Internet seem to be exploding. The increasing traffic demand requires three key factors to keep pace if the Internet...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2010

    Routing in Overlay Multicast Networks

    Multicast services can be provided either as a basic network service or as an application-layer service. Higher level multicast implementations often provide more sophisticated features, and can provide multicast services, where no network layer support is available. Overlay multicast networks offer an intermediate option, potentially combining the flexibility and advanced...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2009

    Enhanced Forward Explicit Congestion Notification (E-FECN) Scheme for Datacenter Ethernet Networks

    Ethernet is replacing the traditional storage networking technologies like Fiber Channel and Infiniband in Datacenters. The key feature of these traditional technologies that make them suitable for datacenter is their low-loss low-delay operation. Consequently IEEE 802.1 standards committee is developing new specification for congestion management for Ethernet in datacenter networks....

    Provided By Washington University in St. Louis

  • White Papers // Jan 2010

    Optimizing Memory Bandwidth of a Multi-Channel Packet Buffer

    Backbone routers typically require large buffers to hold packets during congestion. A thumb rule is to provide a buffer at every link, equal to the product of the round trip time and the link capacity. This translates into Gigabytes of buffers operating at line rate at every link. Such a...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2010

    Analysis of Backward Congestion Notification (BCN) for Ethernet in Datacenter Applications

    IEEE 802.1 standards committee is working on a new specification for congestion notification in Ethernet networks. The goal of this work is to enable application of Ethernet in backend datacenter applications. Such applications typically use Fiber Channel and Infiniband due to their loss-free characteristics. A Backward Congestion Notification (BCN) scheme...

    Provided By Washington University in St. Louis

  • White Papers // Mar 2010

    The Economic Effects Of SOX Section 404 Compliance: A Corporate Insider Perspective

    Based on survey responses from 3,138 corporate insiders, the authors analyze the costs and benefits of compliance with Section 404 of the Sarbanes-Oxley Act of 2002. The vast majority of respondents recognize at least some Section 404 compliance benefits, consistent with it being an effective governance mechanism. The evidence, however,...

    Provided By Washington University in St. Louis

  • White Papers // Nov 2010

    Infrastructure Arrangement for Application Virtualization Services

    This paper first briefly introduces the current development of application virtualization and the Internet usage trend. Implementing application virtualization technologies on mobile computing devices will bring both benefits and challenges. This paper proposes a distributed server arrangement with the corresponding hand-off protocol to provide smooth and responsive user experiences for...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2010

    Capacity Evaluation for IEEE 802.16e Mobile WiMAX

    This paper presents a simple analytical method for capacity evaluation of IEEE 802.16e Mobile WiMAXTM networks. Various overheads that impact the capacity are explained and methods to reduce these overheads are also presented. The advantage of a simple model is that the effect of each decision and sensitivity to various...

    Provided By Washington University in St. Louis

  • White Papers // Dec 2008

    Retaining Talent: Assessing Job Satisfaction Facets Most Significantly Related To Software Developer Turnover Intentions

    Retaining information technology employees has been a problem in many organizations for decades. When key software developers quit, they depart with critical knowledge of business processes and systems that are essential for maintaining a competitive advantage. The primary aim of this paper was to assess facets of job satisfaction that...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    End-to-End Delay Analysis for Fixed Priority Scheduling in WirelessHART Networks

    The WirelessHART standard has been specifically designed for real-time communication between sensor and actuator devices for industrial process monitoring and control. End-to end communication delay analysis for WirelessHART networks is required for acceptance test of real-time data flows from sensors to actuators and for workload adjustment in response to network...

    Provided By Washington University in St. Louis

  • White Papers // Jun 2010

    Design of an Extensible Network Testbed

    Networking testbeds have become an increasingly important part of the networking research cycle. One of the primary reasons for this is that testbeds offer researchers access to network conditions and environments which are very difficult to reproduce in a local laboratory. This work presents the design of the Open Network...

    Provided By Washington University in St. Louis

  • White Papers // Oct 2009

    The Virtual Network Scheduling Problem for Heterogeneous Network Emulation Testbeds

    Network testbeds such as Emulab and the Open Network Laboratory use virtualization to enable users to define end user virtual networks within a shared substrate. This involves mapping users' virtual network nodes onto distinct substrate components and mapping virtual network links onto substrate paths. The mappings guarantee that different user's...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Fast Incremental CRC Updates for IP Over ATM Networks

    In response to the increasing network speeds, many operations in IP routers and similar devices are being made more efficient. With the advances in other areas of packet processing, the verification and regeneration of Cyclic Redundancy Check (CRC) codes of the data link layer is likely to become a bottleneck...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Design of a High Performance Dynamically Extensible Router

    This paper describes the design, implementation and performance of an open, high performance, dynamically extensible router under development at Washington University in St. Louis. This router supports the dynamic installation of software and hardware plugins in the data path of application data flows. It provides an experimental platform for research...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Supporting Collaborative Behavior in MANETs Using Workflows

    Groupware activities provide a powerful representation for many collaborative tasks. Today, the technologies that support typical groupware applications often assume a stable wired network infrastructure. The potential for collaboration in scenarios that lack this fixed infrastructure remains largely untapped. Such scenarios include activities on construction sites, wilderness exploration, disaster recovery,...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Virtualizing Network Processors

    This paper considers the problem of virtualizing the resources of a Network Processor (NP) in order to allow multiple third-parties to execute their own virtual router software on a single physical router at the same time. The broad interest is in designing such a router capable of supporting virtual networking....

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    MobiWork: Mobile Workflow for MANETs

    The workflow model is well suited for scenarios where many entities work collaboratively towards a common goal, and is used widely today to model complex business processes. However, the fundamental workflow model is very powerful and can be applied to a wider variety of application domains. This paper represents an...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Reusable Models for Timing and Liveness Analysis of Middleware for Distributed Real-Time and Embedded Systems

    Distributed Real-time and Embedded (DRE) systems have stringent constraints on timeliness and other properties whose assurance is crucial to correct system behavior. Formal tools and techniques play a key role in verifying and validating system properties. However, many DRE systems are built using middleware frameworks that have grown increasingly complex...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Sliver: A BPEL Workflow Process Execution Engine for Mobile Devices

    The Business Process Execution Language (BPEL) has become the dominant means for expressing traditional business processes as workflows. The widespread deployment of mobile devices like PDAs and mobile phones has created a vast computational and communication resource for these workflows to exploit. However, BPEL so far has been deployed only...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Adaptive Embedded Roadmaps for Sensor Networks

    In this paper, the authors propose a new approach to wireless sensor network assisted navigation while avoiding moving dangers. The approach relies on an embedded roadmap in the sensor network that always contains safe paths. The roadmap is adaptive, i.e., it adapts its topology to changing dangers. Mobile robots in...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    CiAN: A Language and Middleware for Collaboration in Ad Hoc Networks

    Designing software that supports collaboration among multiple users in mobile ad hoc networks is challenging due to the dynamic network topology and inherent unpredictability of the environment. However, as the authors increasingly migrate to using mobile computing platforms, there is a pertinent need for software that can support a wide...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Preserving Performance of Byzantine Fault Tolerant Replica Groups in the Presence of Malicious Clients

    The Castro and Liskov Byzantine Fault Tolerance protocol for replicated state machines (CLBFT) provides a practical means of tolerating arbitrary replica failures in replicated passive data servers. For better performance, CLBFT uses Message Authentication Codes (MAC) instead of public key cryptography to authenticate messages and preserves replica consistency even in...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Mixed-Integer Linear Programming Solution to Multi-Robot Task Allocation Problem

    Multi-robot systems require efficient and accurate planning in order to perform mission-critical tasks. This paper introduces a mixed-integer linear programming solution to coordinate multiple heterogenenous robots for detecting and controlling multiple regions of interest in an unknown environment. The objective function contains four basic requirements of a multi-robot system serving...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Dynamic Resource Management in a Static Network Operating System

    The authors present novel approaches to managing three key resources in an event-driven sensornet OS: memory, energy, and peripherals. They describe the factors that necessitate using these new approaches rather than existing ones. A combination of static allocation and compile-time virtualization isolates resources from one another, while dynamic management provides...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Towards a Unified Radio Power Management Architecture for Wireless Sensor Networks

    In many wireless sensor networks, energy is an extremely limited resource. While many different power management strategies have been proposed to help reduce the amount of energy wasted, application developers still face two fundamental challenges when developing systems with stringent power constraints. First, existing power management strategies are usually tightly...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Virtualization for a Network Processor Runtime System

    The continuing ossification of the Internet is slowing the pace of network innovation. Network diversification presents one solution to this problem, by virtualizing the network at multiple layers. Diversified networks consist of a shared physical substrate, virtual routers (metarouters), and virtual links (metalinks). Virtualizing routers enables smooth and incremental upgrades...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Link Layer Support for Unified Radio Power Management in Wireless Sensor Networks

    Radio power management is of paramount concern in wire-less sensor networks that must achieve long lifetimes on scarce amounts of energy. While a multitude of power management protocols have been proposed in the past, the lack of system support for flexibly integrating them with a diverse set of applications and...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Configurable Component Middleware for Distributed Real-Time Systems With Aperiodic and Periodic Tasks

    Many distributed real-time applications must handle mixed periodic and aperiodic tasks with diverse requirements. However, existing middleware lacks flexible configuration mechanisms needed to manage end-to-end timing easily for a wide range of different applications with both periodic and aperiodic tasks. The primary contribution of this work is the design, implementation...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Context-Aware Publish Subscribe in Mobile Ad Hoc Networks

    The publish-subscribe communication paradigm is enjoying increasing popularity thanks to its ability to simplify the development of complex distributed applications. However, existing solutions in the publish-subscribe domain address only part of the challenges associated with the development of applications in dynamic scenarios such as mobile ad hoc networks. Mobile applications...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Real-Time Query Scheduling for Sensor Networks

    Recent years have seen the emergence of Wireless Sensor Network (WSN) systems that require high data rate real-time communication. This paper proposes Real-Time Query Scheduling (RTQS), a novel approach to conflict-free transmission scheduling for real-time queries in WSNs. The authors show that there is an inherent trade-off between prioritization and...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Network Access in a Diversified Internet

    There is a growing interest in virtualized network infrastructures as a means to enable experimental evaluation of new network architectures on a realistic scale. The National Science Foundation's GENI initiative seeks to develop a national experimental facility that would include virtualized network platforms that can support many concurrent experimental networks....

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Distributed Allocation of Workflow Tasks in MANETs

    When multiple participants work on a workflow that represents a large, collaborative activity, it is important to have a well defined process to determine the portions of the workflow that each participant is responsible for executing. In this paper, the authors describe a process and related algorithms required to assign...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Customizing Component Middleware for Distributed Real-Time Systems With Aperiodic and Periodic Tasks

    Many distributed real-time applications must handle mixed aperiodic and periodic tasks with diverse requirements. However, existing middleware lacks flexible configuration mechanisms needed to manage end-to-end timing easily for a wide range of different applications with both aperiodic and periodic tasks. The primary contribution of this work is the design, implementation...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2009

    Multi-Application Deployment in Integrated Sensing Systems Based on Quality of Monitoring

    Wireless sensor networks are evolving from dedicated application-specific platforms to integrated infrastructure shared by multiple applications. Shared sensor networks offer inherent advantages in terms of flexibility and cost since they allow dynamic resource sharing and allocation among multiple applications. Such shared systems face the critical need for allocation of nodes...

    Provided By Washington University in St. Louis

  • White Papers // Apr 2009

    The Impact of Variability on Soft Real-Time System Scheduling

    Soft real-time systems sometimes operate under uncertain and unpredictable environmental conditions which makes event arrival times unreliable and variable. Input to such systems also change from time to time making event processing times variable. Due to such variations, traditional techniques using worst case times to estimate system performance deviate far...

    Provided By Washington University in St. Louis

  • White Papers // Dec 2008

    Performance Analysis of OpenVPN on a Consumer Grade Router

    Virtual Private Networks (VPNs) offer an alternative solution using Internet Protocol (IP) tunnels to create secure, encrypted communication between geographically distant networks using a common shared medium such as the Internet. They use tunneling to establish end-to-end connectivity. OpenVPN is a cross-platform, secure, highly configurable VPN solution. Security in OpenVPN...

    Provided By Washington University in St. Louis

  • White Papers // Jan 2011

    Architectures for the Future Networks and the Next Generation Internet: A Survey

    The Internet has evolved from being an academic pursuit to a huge commercial commodity. The IP thin waist associated with the simplicity of the present design, has been a remarkable architectural choice, motivated by the need to converge multiple link layer technologies and end-to-end transport mechanisms. However, the assumptions under...

    Provided By Washington University in St. Louis

  • White Papers // Aug 2010

    Better Languages for More Effective Designing

    Developer productivity is strongly influenced by the language(s) used during the design process. The abstraction level of the language as well as the opportunities for casual errors due to non-intuitive language features can both have a dramatic impact on developers. In this paper, the authors explore language design in three...

    Provided By Washington University in St. Louis