University of Minnesota

Displaying 1-40 of 145 results

  • White Papers // May 2012

    Recovery of Low-Rank Plus Compressed Sparse Matrices With Application to Unveiling Traffic Anomalies

    Given the superposition of a low-rank matrix plus the product of a known fat compression matrix times a sparse matrix, the goal of this paper is to establish deterministic conditions under which exact recovery of the low-rank and sparse components becomes possible. This fundamental identifiability issue arises with traffic anomaly...

    Provided By University of Minnesota

  • White Papers // Apr 2012

    Dynamic Network Delay Cartography

    Path delays in IP networks are important metrics, required by network operators for assessment, planning, and fault diagnosis. Monitoring delays of all source-destination pairs in a large network is however challenging and wasteful of resources. The paper advocates a spatio-temporal Kalman filtering approach to construct network-wide delay maps using measurements...

    Provided By University of Minnesota

  • White Papers // Mar 2012

    Scalable Transaction Management With Snapshot Isolation on Cloud Data Management Systems

    Key-value based data storage systems such as HBase and Bigtable provide high scalability compared to traditional relational databases, however, they provide only limited transactional functionality, such as single-row transactions. The authors address the problem of building scalable transaction management mechanisms for multi-row transactions on key-value storage systems. They develop scalable...

    Provided By University of Minnesota

  • White Papers // Aug 2011

    Correlated Flooding in Low-Duty-Cycle Wireless Sensor Networks

    Flooding in low-duty-cycle wireless sensor networks is very costly due to asynchronous schedules of sensor nodes. To adapt existing flooding-tree-based designs for low-duty-cycle networks, the authors shall schedule nodes of common parents wake up simultaneously. Traditionally, energy optimality in a designated flooding-tree is achieved by selecting parents with the highest...

    Provided By University of Minnesota

  • White Papers // Jul 2011

    Safeguarding Schedule Updates in Wireless Sensor Networks

    Working in the duty cycling mode enables sensor nodes to utilize limited energy efficiently instead of unnecessary idle listening. In such networks, awareness of neighboring nodes' working schedules is essential, especially when each node sets up the schedule independently. Most traditional research assumes that a node can always share its...

    Provided By University of Minnesota

  • White Papers // Jun 2011

    Cross-Layer Design of Coded Multicast for Wireless Random Access Networks

    Joint optimization of network coding and Aloha-based Medium Access Control (MAC) for multi-hop wireless networks is considered. The multicast throughput with a power consumption-related penalty is maximized subject to flow conservation and MAC achievable rate constraints to obtain the optimal transmission probabilities. The relevant optimization problem is inherently non-convex and...

    Provided By University of Minnesota

  • White Papers // Jun 2011

    Credit Constraints And Generational Welfare Over The Great Recession

    The Great Recession of 2007-2009 has been one of the largest contractions in the United States since the Great Depression. However, the recession has not impacted all agents equally. Some have lost not only their jobs but also their homes, while others have made fortunes purchasing assets at depressed values....

    Provided By University of Minnesota

  • White Papers // May 2011

    Bubble Trace: Mobile Target Tracking Under Insufficient Anchor Coverage

    As an essential requirement for surveillance systems, target tracking has been studied extensively. Most of the tracking schemes are based on trilateration, which requires each point in the monitoring area to be covered by at least three anchors. However, due to the inadequate deployment of costly anchors and environment constraints,...

    Provided By University of Minnesota

  • White Papers // May 2011

    Sparsity-Aware Kalman Tracking of Target Signal Strengths on a Grid

    Tracking multiple moving targets is known to be challenged by the nonlinearity present in the measurement equation, and by the computationally burdensome data association task. This paper introduces a grid-based model of target signal strengths leading to linear state and measurement equations, that can afford state estimation via sparsity-aware Kalman...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Group Sparse Lasso for Cognitive Network Sensing Robust to Model Uncertainties and Outliers

    To account for variations in the frequency, time, and space dimensions, dynamic re-use of licensed bands under the Cognitive Radio (CR) paradigm calls for innovative network-level sensing algorithms for multi-dimensional spectrum opportunity awareness. Toward this direction, the present paper develops a collaborative scheme whereby CRs cooperate to localize active Primary...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Liquidsoap: A High-Level Programming Language for Multimedia Streaming

    Generating multimedia streams, such as in a netradio, is a task which is complex and difficult to adapt to every users' needs. The authors introduce a novel approach in order to achieve it, based on a dedicated high-level functional programming language, called Liquid-soap, for generating, manipulating and broadcasting multimedia streams....

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Corporate Branding Effects On Consumer Purchase Preferences In Serbian Telecom Market

    This research is carried out to know the role of corporate branding in mobile phone network along with different influencing factors involved in the purchase of mobile telephone connections. This paper discusses corporate branding from consumer's point of view that how much they value it and what type of role...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    The Natural Resource Decision Support System (NRDSS): Creation of a 9.2 ArcGIS Server Website and a SQL Server 2005 ArcSDE 9.2 Database for the Minnesota Board of Water and Soil Resources (BWSR)

    In the fall of 2007, GeoSpatial Services (GSS) accepted a contract from the Minnesota Board of Water and Soil Resources (BWSR) to develop a 9.2 ArcGIS Server application. This application was to be a web mapping site that would support Soils SURvey GeOgraphic Database (SSURGO) soils data interaction and allow...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    The Routing Continuum From Shortest-Path to All-Path: A Unifying Theory

    Routing is a critical operation in many types of networks from communication networks to transportation networks. For instance, in modern IP-based data networks, shortest path routing is most commonly used. In traditional telecommunication networks, dynamic alternative routing strategies that employ paths that are longer than shortest paths have been also...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Flat Versus Metered Rates, Bundling, and "Bandwidth Hogs"

    The current push for bandwidth caps, tiered usage pricing, and other measures in both wireless and wireline communications is usually justified by invoking the specter of "Bandwidth hogs" consuming an unfair share of the transmission capacity and being subsidized by the bulk of the users. This paper presents a conventional...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Business Ethics Pedagogy: A Synthesis Of Paradigms, Philosophies, And Teaching Methods

    Is the job as educators to teach students how to make ethical decisions or is it to teach students how to become innately better people, thus becoming better ethical decision-makers on the job? This paper examines current teaching methods in business ethics. An argument for the necessity of ethics education...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Data Security in the Cloud

    Cloud computing is an emerging trend in the provision of computing resources. For economical reasons users are outsourcing applications and data storage to the cloud, a managed hardware infrastructure providing various services. As the cloud grows it becomes necessary to secure the data and applications from unwanted attackers. This paper...

    Provided By University of Minnesota

  • White Papers // Mar 2011

    Dynamic Outsourcing Mobile Computation to the Cloud

    Mobile devices are becoming the universal interface to online services and cloud computing applications. Since mobile phones have limited computing power and battery life, there is a potential to migrate computation intensive application components to external computing resources. The Cloud is an attractive platform for offloading due to elastic resource...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    Simplifying Manageability, Scalability and Host Mobility in Large-Scale Enterprise Networks Using VEIL-Click

    The explosive growth in the network driven services and devices is causing existing networks to continually expand to accommodate the demands set by them. However, underlying network architecture can not sustain this continual expansion. As a result, several ad-hoc mechanisms are used as workarounds, which make the networks increasingly complicated...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    A Geometric Approach to Robustness in Complex Networks

    Unlike traditional studies on network robustness, that typically treat networks as combinatoric objects and rely primarily on classical graph-theoretic concepts (e.g. minimum cuts) to characterize network robustness, the authors explore a geometric approach which enables one to employ more advanced theories and techniques, quantify and compare robustness of networks in...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    i-Code: A New Approach to Practical Network Coding for Content Distribution

    This paper studies the practicality of network coding to facilitate cooperative content distribution. Network coding is a new data transmission technique which allows any nodes in a network to encode and distribute data. It is a good solution offering reliability and efficiency in distributing content, but network coding has not...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    Trade Liberalization With Endogenous Borrowing Constraints

    A recent empirical literature has documented that credit availability is a significant barrier for firm-level exports. The authors develop a dynamic general equilibrium trade model with heterogeneous monopolistic competitive firms and imperfect credit markets due to limited contract enforce-ability. They show that this model is consistent with the findings of...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    VIRO: A Scalable, Robust and Namespace Independent Virtual Id ROuting for Future Networks

    Today's Internet is increasingly strained to meet the demands and requirements of these Internet services and their users, such as scalability to accommodate the increasing number of network components and host devices, high availability, robustness, mobility and security. As the universal "Glue" that pieces together various heterogeneous physical networks, the...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    Challenges In Demonstrating The Impact Of Overconfidence In M&A Activity

    One of the foundations of behavioral finance is the overconfidence hypothesis. Barberis and Thaler (2003) list it as one of the main beliefs that characterize study in the field. Simply put, the overconfidence hypothesis suggests that the subjects of study (investors or corporate managers) believe that they are more competent...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Efficient Data Collection From Wireless Nodes Under Two-Ring Communication Model

    Research on Wireless Sensor Networks (WSNs) has been very active in the last two decades with researchers focusing on issues ranging from deployments with coverage guarantees to the development of energy-efficient communication protocols to improve network lifetime. Consequently, the technology advanced to the level that WSNs are now being routinely...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Un-Zipping Cellular Infrastructure Locations Via User Geo-Intent

    Despite the rapid growth in cellular data traffic, the authors know very little about the (operational) Cellular Data Service Network (CDSN) infrastructure. A key step in the process of developing any such understanding is to first understand the locations and distribution of the base-stations in the CDSN infrastructure that serve...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Making Sense of Customer Tickets in Cellular Networks

    Effective management of large-scale cellular data networks is critical to meet customer demands and expectations. Customer calls for technical support provide direct indication as to the problems customers encounter. In this paper, the authors study the customer tickets - free-text recordings and classifications by customer support agents - collected at...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    A First Look at Inter-Data Center Traffic Characteristics Via Yahoo! Datasets

    Recent years have seen unprecedented growth in the data center driven technologies and services. Various organizations are now sourcing their computing to "Cloud-based" infrastructures. Therefore, large scale data centers and associated cloud services are developed and deployed by various organizations and service providers to store massive amounts of data, and...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Deuteronomy: Transaction Support for Cloud Data

    The Deuteronomy system supports efficient and scalable ACID transactions in the cloud by decomposing functions of a database storage engine kernel into: a Transactional Component (TC) that manages transactions and their "Logical" concurrency control and undo/redo recovery, but knows nothing about physical data location and a Data Component (DC) that...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    On-Demand Time Synchronization With Predictable Accuracy

    Time synchronization remains as a challenging task in wireless sensor networks that face severe resource constraints. Unlike previous work's aiming at pure clock accuracy, this paper proposes On-Demand Synchronization (ODS), a design to achieve efficient clock synchronization with customized performance. By carefully modeling the error uncertainty of skew detection and...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Proxy-Assisted Periodic Broadcast for Video Streaming With Multiple Servers

    Large scale video streaming over Internet requires a large amount of resources such as server I/O bandwidth, network bandwidth. A number of video delivery techniques can be used to lower these requirements. Periodic broadcast by a central server combined with proxy caching offers a significant reduction of the aggregate network...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Proxy-Assisted Periodic Broadcast Architecture for Large-Scale Video Streaming

    Many multimedia applications rely on video streaming techniques. However, large scale video delivery is still challenging since it requires a large amount of resources. This paper proposes a proxy-assisted periodic broadcast architecture for video delivery to a large number of clients over the Internet. The video delivery technique is based...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Heterogeneity-Aware Workload Distribution in Donation-Based Grids

    In this paper, the authors explore the tradeoffs and opportunities in porting a high-throughput Grid computing middleware to a high-performance service oriented environment. They present the limitations of the Grid computing middleware when operating in such a performance sensitive environment and suggest ways of overcoming these limitations. They focus on...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Practical Techniques for Eliminating Storage of Deleted Data

    The layered design of modern file systems hides the liveness of data from the underlying storage systems. In this paper, the authors define a generic "Purge" operation that can be used by a file system to pass liveness information to the storage system with minimal changes in the layer interfaces....

    Provided By University of Minnesota

  • White Papers // Dec 2010

    The Distributed Virtual Network for High Fidelity, Large Scale Peer to Peer Network Simulation

    The ability to analyze the behavior of large distributed systems can be limited by the modeling tools used. The Distributed Virtual Network (DVN) is a discrete event network simulator providing a platform for realistic, high fidelity, scalable and repeatable simulations of large distributed systems. With a global view of the...

    Provided By University of Minnesota

  • White Papers // Nov 2010

    Optimized Multi-Antenna Communication in Ad-Hoc Networks With Opportunistic Routing

    The authors consider the problem of using multiple antennas to maximize end-to-end performance in a multi-hop ad hoc wireless network with opportunistic routing. They find that when a single data stream is sent per-hop, performance is maximized by aggressively increasing spatial reuse, as opposed to increasing per-hop length or rate....

    Provided By University of Minnesota

  • White Papers // Nov 2010

    HOSPITAL: Host and Network System Profiler and Internet Traffic Analyzer

    The ever-increasing complexity and diversity of the Internet pose several challenges to network operators and administrators and, in general, Internet users. More specifically, because of the diversity in applications and usage patterns; the prevalence of dynamic IP addresses and applications that do not conform to standard configuration (e.g. VoIP to...

    Provided By University of Minnesota

  • White Papers // Oct 2010

    Dynamic Switching-Based Data Forwarding for Low-Duty-Cycle Wireless Sensor Networks

    In this paper, the authors introduce the concept of Dynamic Switch-based Forwarding (DSF) that optimizes the expected data delivery ratio, expected communication delay, or expected energy consumption for low-duty-cycle wireless sensor networks under unreliable communication links. DSF is designed for networks with possibly unreliable communication links and predetermined node communication...

    Provided By University of Minnesota

  • White Papers // Oct 2010

    VEIL-Click: Creating Advanced Large-Scale Ethernet Networks

    VEIL (Virtual Ethernet Identifier Layer) is a novel concept for below IP networking. It addresses the scalability, efficiency and reliability challenges facing the traditional Ethernet, while retaining its simplicity. Furthermore, it provides a uniform (Below IP) convergence layer to support a large, dynamic and heterogeneous (Layer-2) network that is capable...

    Provided By University of Minnesota

  • White Papers // Oct 2010

    Exact Hamming Distortion Analysis of Viterbi Encoded Trellis Coded Quantizers

    Let G be a finite strongly connected aperiodic directed graph in which each edge carries a label from a finite alphabet A. Then G induces a trellis coded quantizer for encoding an alphabet A memoryless source. A source sequence of long finite length is encoded by finding a path in...

    Provided By University of Minnesota

  • White Papers // Sep 2008

    Rethinking MIMO for Wireless Networks: Linear Throughput Increases With Multiple Receive Antennas

    The benefit of multiple antenna communication is investigated in wireless ad hoc networks, and the primary finding is that throughput can be made to scale linearly with the number of receive antennas even if each transmitting node uses only a single antenna. The linear throughput gain is achieved by using...

    Provided By University of Minnesota

  • White Papers // May 2011

    Bubble Trace: Mobile Target Tracking Under Insufficient Anchor Coverage

    As an essential requirement for surveillance systems, target tracking has been studied extensively. Most of the tracking schemes are based on trilateration, which requires each point in the monitoring area to be covered by at least three anchors. However, due to the inadequate deployment of costly anchors and environment constraints,...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    On-Demand Time Synchronization With Predictable Accuracy

    Time synchronization remains as a challenging task in wireless sensor networks that face severe resource constraints. Unlike previous work's aiming at pure clock accuracy, this paper proposes On-Demand Synchronization (ODS), a design to achieve efficient clock synchronization with customized performance. By carefully modeling the error uncertainty of skew detection and...

    Provided By University of Minnesota

  • White Papers // Mar 2010

    Coding Versus ARQ in Fading Channels: How reliable should the PHY be?

    This paper studies the tradeoff between channel coding and ARQ (Automatic Repeat reQuest) in Rayleigh block-fading channels. A heavily coded system corresponds to a low transmission rate with few ARQ re-transmissions, whereas lighter coding corresponds to a higher transmitted rate but more retransmissions. The optimum error probability, where optimum refers...

    Provided By University of Minnesota

  • White Papers // Mar 2012

    Scalable Transaction Management With Snapshot Isolation on Cloud Data Management Systems

    Key-value based data storage systems such as HBase and Bigtable provide high scalability compared to traditional relational databases, however, they provide only limited transactional functionality, such as single-row transactions. The authors address the problem of building scalable transaction management mechanisms for multi-row transactions on key-value storage systems. They develop scalable...

    Provided By University of Minnesota

  • White Papers // Jul 2008

    Application-Level Recovery Mechanisms for Context-Aware Pervasive Computing

    The authors identify here various kinds of failure conditions and robustness issues that arise in context-aware pervasive computing applications. Such conditions are related to failures in an application's interactions with ambient services, failures in resource discovery and binding, and invalidation of context conditions during the execution of an application task....

    Provided By University of Minnesota

  • White Papers // May 2011

    Sparsity-Aware Kalman Tracking of Target Signal Strengths on a Grid

    Tracking multiple moving targets is known to be challenged by the nonlinearity present in the measurement equation, and by the computationally burdensome data association task. This paper introduces a grid-based model of target signal strengths leading to linear state and measurement equations, that can afford state estimation via sparsity-aware Kalman...

    Provided By University of Minnesota

  • White Papers // Apr 2012

    Dynamic Network Delay Cartography

    Path delays in IP networks are important metrics, required by network operators for assessment, planning, and fault diagnosis. Monitoring delays of all source-destination pairs in a large network is however challenging and wasteful of resources. The paper advocates a spatio-temporal Kalman filtering approach to construct network-wide delay maps using measurements...

    Provided By University of Minnesota

  • White Papers // May 2012

    Recovery of Low-Rank Plus Compressed Sparse Matrices With Application to Unveiling Traffic Anomalies

    Given the superposition of a low-rank matrix plus the product of a known fat compression matrix times a sparse matrix, the goal of this paper is to establish deterministic conditions under which exact recovery of the low-rank and sparse components becomes possible. This fundamental identifiability issue arises with traffic anomaly...

    Provided By University of Minnesota

  • White Papers // May 2009

    Exploring In-Situ Sensing Irregularity in Wireless Sensor Networks

    The circular sensing model has been widely used to estimate performance of sensing applications in existing analyses and simulations. While this model provides valuable high-level guidelines, the quantitative results obtained may not reflect the true performance of these applications, due to the sensing irregularity introduced by existence of obstacles in...

    Provided By University of Minnesota

  • White Papers // Apr 2009

    Impact of Fading on the Performance of ALOHA and CSMA

    This paper considers the performance of the ALOHA and CSMA MAC protocols in wireless ad hoc networks in the presence of fading. Increasing the rate of successful reception of packets is the authors' objective, and thus, outage probability is used as the performance evaluation metric. In their network model, packets...

    Provided By University of Minnesota

  • White Papers // Sep 2009

    Joint Transmitter and Receiver Carrier Sensing Capability of CSMA in MANETs

    This paper considers the performance of the CSMA protocol with joint transmitter-receiver sensing in a wireless mobile ad hoc network. In the authors' network model, packets belonging to specific transmitters arrive randomly in space and time according to a 3-D Poisson point process, and are then transmitted to their intended...

    Provided By University of Minnesota

  • White Papers // Jan 2010

    Stochastic Cross-Layer Resource Allocation for Wireless Networks Using Orthogonal Access: Optimality and Delay Analysis

    Efficient design of wireless networks requires implementation of cross-layer algorithms that exploit channel state information. Capitalizing on convex optimization and stochastic approximation tools, this paper develops a stochastic algorithm that allocates resources at network, link, and physical layers so that a sum-utility of the average end-to-end rates is maximized. Focus...

    Provided By University of Minnesota

  • White Papers // May 2008

    Optimal Stochastic Dual Resource Allocation for Cognitive Radios Based on Quantized CSI

    The present paper deals with dynamic resource management based on quantized Channel State Information (CSI) for multi-carrier cognitive radio networks comprising primary and secondary wireless users. For each sub-carrier, users rely on adaptive modulation, coding and power modes that they select in accordance with the limited-rate feedback they receive from...

    Provided By University of Minnesota

  • White Papers // Mar 2010

    Efficient Evaluation of K-Range Nearest Neighbor Queries in Road Networks

    A k-Range Nearest Neighbor (or kRNN for short) query in road networks finds the k nearest neighbors of every point on the road segments within a given query region based on the network distance. The kRNN query is significantly important for location-based applications in many realistic scenarios. For example, the...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    The Natural Resource Decision Support System (NRDSS): Creation of a 9.2 ArcGIS Server Website and a SQL Server 2005 ArcSDE 9.2 Database for the Minnesota Board of Water and Soil Resources (BWSR)

    In the fall of 2007, GeoSpatial Services (GSS) accepted a contract from the Minnesota Board of Water and Soil Resources (BWSR) to develop a 9.2 ArcGIS Server application. This application was to be a web mapping site that would support Soils SURvey GeOgraphic Database (SSURGO) soils data interaction and allow...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    A Geometric Approach to Robustness in Complex Networks

    Unlike traditional studies on network robustness, that typically treat networks as combinatoric objects and rely primarily on classical graph-theoretic concepts (e.g. minimum cuts) to characterize network robustness, the authors explore a geometric approach which enables one to employ more advanced theories and techniques, quantify and compare robustness of networks in...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    The Routing Continuum From Shortest-Path to All-Path: A Unifying Theory

    Routing is a critical operation in many types of networks from communication networks to transportation networks. For instance, in modern IP-based data networks, shortest path routing is most commonly used. In traditional telecommunication networks, dynamic alternative routing strategies that employ paths that are longer than shortest paths have been also...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Flat Versus Metered Rates, Bundling, and "Bandwidth Hogs"

    The current push for bandwidth caps, tiered usage pricing, and other measures in both wireless and wireline communications is usually justified by invoking the specter of "Bandwidth hogs" consuming an unfair share of the transmission capacity and being subsidized by the bulk of the users. This paper presents a conventional...

    Provided By University of Minnesota

  • White Papers // Feb 2011

    Simplifying Manageability, Scalability and Host Mobility in Large-Scale Enterprise Networks Using VEIL-Click

    The explosive growth in the network driven services and devices is causing existing networks to continually expand to accommodate the demands set by them. However, underlying network architecture can not sustain this continual expansion. As a result, several ad-hoc mechanisms are used as workarounds, which make the networks increasingly complicated...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Making Sense of Customer Tickets in Cellular Networks

    Effective management of large-scale cellular data networks is critical to meet customer demands and expectations. Customer calls for technical support provide direct indication as to the problems customers encounter. In this paper, the authors study the customer tickets - free-text recordings and classifications by customer support agents - collected at...

    Provided By University of Minnesota

  • White Papers // Jan 2011

    Un-Zipping Cellular Infrastructure Locations Via User Geo-Intent

    Despite the rapid growth in cellular data traffic, the authors know very little about the (operational) Cellular Data Service Network (CDSN) infrastructure. A key step in the process of developing any such understanding is to first understand the locations and distribution of the base-stations in the CDSN infrastructure that serve...

    Provided By University of Minnesota

  • White Papers // Nov 2010

    HOSPITAL: Host and Network System Profiler and Internet Traffic Analyzer

    The ever-increasing complexity and diversity of the Internet pose several challenges to network operators and administrators and, in general, Internet users. More specifically, because of the diversity in applications and usage patterns; the prevalence of dynamic IP addresses and applications that do not conform to standard configuration (e.g. VoIP to...

    Provided By University of Minnesota

  • White Papers // Feb 2010

    Inferring Applications at the Network Layer Using Collective Traffic Statistics

    Operating, managing and securing networks require a thorough understanding of the demands placed on the network by the endpoints it interconnects, the characteristics of the traffic the endpoints generate, and the distribution of that traffic over the resources of the network infrastructure. A major differentiator in the types of resource...

    Provided By University of Minnesota

  • White Papers // Mar 2010

    Sifting Through Network Data to Cull Activity Patterns With HEAPs

    Today's large campus and enterprise networks are characterized by their complexity, i.e. containing thousands of hosts, and diversity, i.e. with various applications and usage patterns. To effectively manage and secure such networks, network operators and system administrators are faced with the challenge of characterizing, profiling and tracking activity patterns passing...

    Provided By University of Minnesota

  • White Papers // Jul 2009

    Interaction, Competition and Innovation in a Service-Oriented Internet: An Economic Model

    This paper presents a new economic approach for studying competition and innovation in a complex and highly interactive system of network providers, users, and suppliers of digital goods and services (i.e., service providers). It employs Cournot and Bertrand games to model the competition among service providers and among network providers,...

    Provided By University of Minnesota

  • White Papers // Jan 2009

    Identifying High Cardinality Internet Hosts

    The Internet host cardinality, defined as the number of distinct peers that an Internet host communicates with, is an important metric for profiling Internet hosts. Some example applications include behavior based network intrusion detection, p2p hosts identification, and server identification. However, due to the tremendous number of hosts in the...

    Provided By University of Minnesota

  • White Papers // Oct 2008

    Codesigning the Failure Analysis and Monitoring of Large-Scale Systems

    Large-scale distributed systems provide the backbone for numerous distributed applications and online services. These systems span over a multitude of computing nodes located at different geographical locations connected together via wide-area networks and overlays. A major concern with such systems is their susceptibility to failures leading to downtime of services...

    Provided By University of Minnesota

  • White Papers // Apr 2011

    Liquidsoap: A High-Level Programming Language for Multimedia Streaming

    Generating multimedia streams, such as in a netradio, is a task which is complex and difficult to adapt to every users' needs. The authors introduce a novel approach in order to achieve it, based on a dedicated high-level functional programming language, called Liquid-soap, for generating, manipulating and broadcasting multimedia streams....

    Provided By University of Minnesota

  • White Papers // May 2008

    Mixed-Drove Spatio-Temporal Co-Occurrence Pattern Mining

    Mixed-Drove spatio-temporal Co-Occurrence Patterns (MDCOPs) represent subsets of two or more different object-types whose instances are often located in spatial and temporal proximity. Discovering MDCOPs is an important problem with many applications such as identifying tactics in battlefields, games, and predator-prey interactions. However, mining MDCOPs is computationally very expensive because...

    Provided By University of Minnesota

  • White Papers // Aug 2008

    VISA: Virtual Scanning Algorithm for Dynamic Protection of Road Networks

    This paper proposes a VIrtual Scanning Algorithm (VISA), tailored and optimized for road network surveillance. The authors' design uniquely leverages upon the facts that the movement of targets (e.g., vehicles) is confined within roadways and the road network maps are normally known. They guarantee the detection of moving targets before...

    Provided By University of Minnesota

  • White Papers // Nov 2008

    OPEN: Passive Network Performance Estimation for Data-Intensive Applications

    Distributed computing applications are increasingly utilizing distributed data sources. However, the unpredictable cost of data access in large-scale computing infrastructures can lead to severe performance bottlenecks. Providing predictability in data access is thus essential to accommodate the large set of newly emerging large-scale, data-intensive computing applications. In this regard, accurate...

    Provided By University of Minnesota

  • White Papers // Aug 2011

    Correlated Flooding in Low-Duty-Cycle Wireless Sensor Networks

    Flooding in low-duty-cycle wireless sensor networks is very costly due to asynchronous schedules of sensor nodes. To adapt existing flooding-tree-based designs for low-duty-cycle networks, the authors shall schedule nodes of common parents wake up simultaneously. Traditionally, energy optimality in a designated flooding-tree is achieved by selecting parents with the highest...

    Provided By University of Minnesota

  • White Papers // May 2010

    Bounding Communication Delay in Energy Harvesting Sensor Networks

    In energy-harvesting sensor networks, limited ambient energy from environment necessitates sensor nodes to operate at a low-duty-cycle, i.e., they communicate briefly and stay asleep most of time. Such low-duty-cycle operation leads to orders of magnitude longer communication delays in comparison with traditional always-active networks, imposing a new challenge in many...

    Provided By University of Minnesota

  • White Papers // Sep 2009

    Spatiotemporal Delay Control for Low-Duty-Cycle Sensor Networks

    Data delivery is a major function of sensor network applications. Many applications, such as military surveillance, require the detection of interested events to be reported to a command center within a specified time frame, and therefore impose a real-time bound on communication delay. On the other hand, to conserve energy,...

    Provided By University of Minnesota

  • White Papers // Sep 2009

    ESC: Energy Synchronized Communication in Sustainable Sensor Networks

    With advances in energy harvesting techniques, it is now feasible to build Sustainable Sensor Networks (SSN) to support long-term applications. Unlike battery-powered sensor networks, the objective of sustainable sensor networks is to effectively utilize a continuous stream of ambient energy. Instead of pushing the limits of energy conservation, the authors...

    Provided By University of Minnesota

  • White Papers // Oct 2009

    Virtual Scanning Algorithm for Road Network Surveillance

    This paper proposes a VIrtual Scanning Algorithm (VISA), tailored and optimized for road network surveillance. The authors' design uniquely leverages upon the facts that the movement of targets (e.g., vehicles) is confined within roadways and the road network maps are normally known. They guarantee the detection of moving targets before...

    Provided By University of Minnesota

  • White Papers // Jul 2011

    Safeguarding Schedule Updates in Wireless Sensor Networks

    Working in the duty cycling mode enables sensor nodes to utilize limited energy efficiently instead of unnecessary idle listening. In such networks, awareness of neighboring nodes' working schedules is essential, especially when each node sets up the schedule independently. Most traditional research assumes that a node can always share its...

    Provided By University of Minnesota

  • White Papers // Oct 2010

    Dynamic Switching-Based Data Forwarding for Low-Duty-Cycle Wireless Sensor Networks

    In this paper, the authors introduce the concept of Dynamic Switch-based Forwarding (DSF) that optimizes the expected data delivery ratio, expected communication delay, or expected energy consumption for low-duty-cycle wireless sensor networks under unreliable communication links. DSF is designed for networks with possibly unreliable communication links and predetermined node communication...

    Provided By University of Minnesota

  • White Papers // Jun 2003

    The Effectiveness and Safety of Traffic and Non-Traffic Related Messages Presented on Changeable Message Signs (CMS)

    This report discusses two experiments investigating Changeable Message Signs (CMS). The objectives of this study were to determine whether or not CMS messages really work, whether or not CMS messages cause traffic slow-downs, the likely impact of CMS messages on traffic flow, and whether or not messages should be presented...

    Provided By University of Minnesota