University of Mary Washington

Displaying 1-40 of 150 results

  • White Papers // May 2014

    Efficient Implementation of Hyperspectral Anomaly Detection Techniques on GPUs and Multicore Processors

    Anomaly detection is an important task for hyperspectral data exploitation. Although many algorithms have been developed for this purpose in recent years, due to the large dimensionality of hyperspectral image data, fast anomaly detection remains a challenging task. In this paper, the authors exploit the computational power of commodity Graphics...

    Provided By University of Mary Washington

  • White Papers // Mar 2014

    Oblivious Data Structures

    The authors are among the first to systematically investigate (memory-trace) oblivious data structures. They propose a framework for constructing a variety of oblivious data structures, achieving asymptotic performance gains in comparison with generic Oblivious RAM (ORAM). They evaluate the performance of their oblivious data structures in terms of their bandwidth...

    Provided By University of Mary Washington

  • White Papers // Mar 2014

    Verifiable Oblivious Storage

    The authors formalize the notion of Verifiable Oblivious Storage (VOS), where a client outsources the storage of data to a server while ensuring data confidentiality, access pattern privacy, and integrity and freshness of data accesses. VOS generalizes the notion of Oblivious RAM (ORAM) in that it allows the server to...

    Provided By University of Mary Washington

  • White Papers // Jan 2014

    Hierarchical Interconnects for On-Chip Clustering

    In the sub-micron technology era, wire delays are becoming much more important than gate delays, making it particularly attractive to go for clustered designs. A common form of clustering adopted in processors is to replace the centralized instruction scheduler with multiple smaller schedulers that work in parallel within a single...

    Provided By University of Mary Washington

  • White Papers // Dec 2013

    Practical Dynamic Searchable Encryption with Small Leakage

    Dynamic Searchable Symmetric Encryption (DSSE) enables a client to encrypt their document collection in a way that it is still searchable and efficiently updatable. However, all DSSE constructions that have been presented in the literature so far come with several problems: Either they leak a significant amount of information (e.g.,...

    Provided By University of Mary Washington

  • White Papers // Nov 2013

    Optimal Locally Repairable Codes and Connections to Matroid Theory

    Petabyte-scale distributed storage systems are currently transitioning to erasure codes to achieve higher storage efficiency. Classical codes like reed-solomon are highly sub-optimal for distributed environments due to their high overhead in single-failure events. Locally Repairable Codes (LRCs) form a new family of codes that are repair efficient. In particular, LRCs...

    Provided By University of Mary Washington

  • White Papers // Aug 2013

    Schema Extraction for Tabular Data on the Web

    Tabular data is an abundant source of information on the web, but remains mostly isolated from the latter are interconnections since tables lack links and computer-accessible descriptions of their structure. In other words, the schemas of these tables - attribute names, values, data types, etc. - are not explicitly stored...

    Provided By University of Mary Washington

  • White Papers // Aug 2013

    Hone: \"Scaling Down\" Hadoop on Shared-Memory Systems

    The underlying assumption behind Hadoop and, more generally, the need for distributed processing is that the data to be analyzed cannot be held in memory on a single machine. Today, this assumption needs to be re-evaluated. Although petabyte-scale data-stores are increasingly common, it is unclear whether \"Typical\" analytics tasks require...

    Provided By University of Mary Washington

  • White Papers // Jun 2013

    Efficient Secure Two-Party Computation Using Symmetric Cut-and-Choose

    Beginning with the work of Lindell and Pinkas, researchers have proposed several protocols for secure two-party computation based on the cut-and-choose paradigm. In existing instantiations of this paradigm, one party generates K garbled circuits; some fraction of those is \"Checked\" by the other party, and the remaining fraction is evaluated....

    Provided By University of Mary Washington

  • White Papers // May 2013

    Optimal Scheduling for Energy Harvesting Transmitters With Hybrid Energy Storage

    The authors consider data transmission with an energy harvesting transmitter which has a hybrid energy storage unit composed of a perfectly efficient Super-Capacitor (SC) and an inefficient battery. The SC has finite space for energy storage while the battery has unlimited space. The transmitter can choose to store the harvested...

    Provided By University of Mary Washington

  • White Papers // May 2013

    Binary Energy Harvesting Channel With Finite Energy Storage

    The authors consider the capacity of an energy harvesting communication channel with a finite-sized battery. As an abstraction of this problem, they consider a system where energy arrives at the encoder in multiples of a fixed quantity, and the physical layer is modeled accordingly as a finite discrete alphabet channel...

    Provided By University of Mary Washington

  • White Papers // May 2013

    An Improved Sub-Packetization Bound for Minimum Storage Regenerating Codes

    Distributed storage systems employ codes to provide resilience to failure of multiple storage disks. Specifically, an (n, k) MDS code stores k symbols in n disks such that the overall system is tolerant to a failure of up to n-k disks. However, access to at least k disks is still...

    Provided By University of Mary Washington

  • White Papers // May 2013

    Non-Asymptotic and Second-Order Achievability Bounds for Source Coding with Side-Information

    In this paper, the authors proved a new non-asymptotic bound on the error probability for the WAK problem. They present a novel achievability bound for the Wyner-Ahlswede-Korner (WAK) problem of lossless source coding with rate-limited side-information. This bound is proved using ideas from channel simulation and channel resolvability. The bound...

    Provided By University of Mary Washington

  • White Papers // May 2013

    An Implementation of Binomial Method of Option Pricing using Parallel Computing

    The Binomial method of option pricing is based on iterating over discounted option payoffs in a recursive fashion to calculate the present value of an option. Implementing the Binomial method to exploit the resources of a parallel computing cluster is non-trivial as the method is not easily parallelizable. The authors...

    Provided By University of Mary Washington

  • White Papers // Apr 2013

    Memory Trace Oblivious Program Execution

    Cloud computing allows users to delegate data and computation to cloud service providers, at the cost of giving up physical control of their computing infrastructure. An attacker with physical access to the computing platform can perform various physical attacks, including probing memory buses and cold-boot style attacks. Previous work on...

    Provided By University of Mary Washington

  • White Papers // Mar 2013

    Access vs. Bandwidth in Codes for Storage

    Erasure-correcting codes are the basis for widely used storage systems, where disks (nodes) correspond to symbols in the code. An important family of codes is the Maximum Distance Separable (MDS) codes, which provide an optimal resiliency to erasures for a given amount of redundancy. Namely, an MDS code with r...

    Provided By University of Mary Washington

  • White Papers // Mar 2013

    On Sharing Private Data with Multiple NonColluding Adversaries

    The authors present SPARSI, a novel theoretical framework for partitioning sensitive data across multiple non-colluding adversaries. Most work in privacy-aware data sharing has considered disclosing summaries where the aggregate information about the data is preserved, but sensitive user information is protected. Nonetheless, there are applications, including online advertising, cloud computing...

    Provided By University of Mary Washington

  • White Papers // Mar 2013

    Technical Report: Does Malware Detection Improve with Diverse AntiVirus Products? an Empirical Study

    The authors present results of an empirical study to evaluate the detection capability of diverse Anti-Virus products (AVs). They have used malware samples that have been collected in a geographically distributed honeypot deployment in several different countries and organizations. The malware have been collected in August 2012; therefore the results...

    Provided By University of Mary Washington

  • White Papers // Mar 2013

    Spread Identity : A New Dynamic Address Remapping Mechanism for Anonymity and DDoS Defense

    The authors present and experimentally evaluate Spread Identity (SI) - a new dynamic network address remapping mechanism that provides anonymity and DDoS defense capabilities for Internet communications. For each session between a source and destination host, the trusted source gateway dynamically and randomly assigns an IP address for the source...

    Provided By University of Mary Washington

  • White Papers // Feb 2013

    Secure Degrees of Freedom of the Gaussian Wiretap Channel With Helpers and No Eavesdropper CSI: Blind Cooperative Jamming

    Wyner introduced the wiretap channel in which a legitimate transmitter wants to have secure communications with a legitimate receiver in the presence of an eavesdropper, and determined its capacity-equivocation region for the degraded case. Csiszar and Korner extended this result to the general, not necessarily degraded, wiretap channel. Leung-Yan-Cheong and...

    Provided By University of Mary Washington

  • White Papers // Feb 2013

    Energy Cooperation in Energy Harvesting Two-Way Communications

    In this paper, the authors investigate a two-way communication channel where users can harvest energy from nature and energy can be transferred in one-way from one of the users to the other. Energy required for data transmission is randomly harvested by the users throughout the communication duration and users have...

    Provided By University of Mary Washington

  • White Papers // Jan 2013

    An Outer Bound for Multiple Access Channels with Correlated Sources

    The capacity region of the multiple access channel with correlated sources remains an open problem. Cover, El Gamal and Salehi gave an achievable region in the form of single-letter entropy and mutual information expressions, without a single-letter converse. Cover, El Gamal and Salehi also suggested a converse in terms of...

    Provided By University of Mary Washington

  • White Papers // Jan 2013

    The Capacity Region of a Class of Discrete Degraded Interference Channels

    The authors provide a single-letter characterization for the capacity region of a class of Discrete Degraded Interference Channels (DDICs). The class of DDICs considered includes the Discrete Additive Degraded Interference Channel (DADIC) studied by Benzel. They show that for the class of DDICs studied, encoder cooperation does not increase the...

    Provided By University of Mary Washington

  • White Papers // Jan 2013

    Optimization Based Rate Control for Multirate Multicast Sessions

    Multi-rate multicasting, where the receivers of a multicast group can receive service at different rates, is an efficient mode of data delivery for many real-time applications. In this paper, the authors address the problem of achieving rates that maximize the total receiver utility for multi-rate multicast sessions. This problem not...

    Provided By University of Mary Washington

  • White Papers // Jan 2013

    A Simple Rate Control Algorithm for Maximizing Total User Utility

    In this paper, the authors consider the rate control problem with the objective of maximizing the total user utility. It takes into account the possible differences in user requirements, and also provides a framework for achieving a wide range of fairness objectives. They propose a simple algorithm for achieving the...

    Provided By University of Mary Washington

  • White Papers // Dec 2012

    Technology Comparison for Large Last-Level Caches (L3Cs): Low-Leakage SRAM, Low Write-Energy STT-RAM, and Refresh-Optimized eDRAM

    Large Last-Level Caches (L3Cs) are frequently used to bridge the performance and power gap between processor and memory. Although traditional processors implement caches as SRAMs, technologies such as STT-RAM Magnetoresistive Random-Access Memory (MRAM), and eDRAM have been used and/or considered for the implementation of L3Cs. Each of these technologies has...

    Provided By University of Mary Washington

  • White Papers // Dec 2012

    Two-Way and Multiple-Access Energy Harvesting Systems With Energy Cooperation

    The authors study the capacity regions of the Gaussian Two-Way Channel (TWC) and the Gaussian two-user Multiple Access Channel (MAC) with one-way energy transfer. In both scenarios, there are two users powered by energy harvesting devices communicating messages to each other or to an access point. They model these scenarios...

    Provided By University of Mary Washington

  • White Papers // Dec 2012

    Runtime Optimizations for Prediction with Tree-Based Models

    Tree-based models have proven to be an effective solution for web ranking as well as other problems in diverse domains. This paper focuses on optimizing the runtime performance of applying such models to make predictions, given an already trained model. Although exceedingly simple conceptually, most implementations of tree-based models do...

    Provided By University of Mary Washington

  • White Papers // Dec 2012

    An Efficient CCA2-Secure Variant of the McEliece Cryptosystem in the Standard Model

    Recently, a few Chosen Ciphertext Attacks secure (CCA2-secure) variants of the McEliece Public-Key Encryption (PKE) scheme in the standard model were introduced. All the proposed schemes are based on encryption repetition paradigm and use general transformation from CPA-secure scheme to a CCA2- secure one. Therefore, the resulting encryption scheme needs...

    Provided By University of Mary Washington

  • White Papers // Dec 2012

    Verifiable Data Streaming

    In a verifiable data streaming protocol, the client streams a long string to the server who stores it in its database. The stream is verifiable in the sense that the server can neither change the order of the elements nor manipulate them. The client may also retrieve data from the...

    Provided By University of Mary Washington

  • White Papers // Nov 2012

    Anti Error Propagation Methods for Wireless Uplink Using Network Coding

    Wireless network coding suffers the error propagation issues that may severely degrade the diversity performance. In this paper, the authors develop two power scaling schemes at the relay side and two detection schemes at the receiver side, respectively, to mitigate error propagation in network-coded uplink channel and thus achieve full...

    Provided By University of Mary Washington

  • White Papers // Nov 2012

    Probabilistic Computation for Information Security

    Probabilistic computation is a convenient means of mechanically reasoning about a variety of information security problems. At its core, information security concerns itself with measuring or limiting the knowledge an adversary might attain from interacting with a protected system. Probabilistic inference lets one compute this knowledge explicitly as long as...

    Provided By University of Mary Washington

  • White Papers // Oct 2012

    Multi-View Constrained Clustering with an Incomplete Mapping Between Views

    Multi-view learning algorithms typically assume a complete bipartite map-ping between the different views in order to exchange information during the learning process. However, many applications provide only a partial mapping between the views, creating a challenge for current methods. To address this problem, the authors propose a multi-view algorithm based...

    Provided By University of Mary Washington

  • White Papers // Oct 2012

    Systematic Integration of Flowgraph- and Module-Level Parallelism in Implementation of DSP Applications on Multiprocessor Systems-on-Chip

    Increasing use of Multi-Processor System-on-Chip (MPSoC) technology is an important trend in the design and implementation of signal processing systems. However, the design of efficient DSP software for MPSoC platforms involves complex inter-related steps, including data decomposition, memory management, and inter-task and inter-thread synchronization. These design steps are challenging, especially...

    Provided By University of Mary Washington

  • White Papers // Sep 2012

    Secure Degrees of Freedom of the Gaussian Wiretap Channel With Helpers

    The secrecy capacity of the canonical Gaussian wiretap channel does not scale with the transmit power, and hence, the secure d.o.f. of the Gaussian wiretap channel with no helpers is zero. It has been known that a strictly positive secure d.o.f. can be obtained in the Gaussian wiretap channel by...

    Provided By University of Mary Washington

  • White Papers // Sep 2012

    Secure Degrees of Freedom of One-Hop Wireless Networks

    The authors study the secure Degrees of Freedom (DoF) of one-hop wireless networks by considering four fundamental wireless network structures: Gaussian wiretap channel, Gaussian broadcast channel with confidential messages, Gaussian interference channel with confidential messages, and Gaussian multiple access wiretap channel. The secrecy capacity of the canonical Gaussian wiretap channel...

    Provided By University of Mary Washington

  • White Papers // Sep 2012

    Cluster-Based Instance Consolidation for Subsequent Matching

    Instance consolidation is a way to merge instances that are thought to be the same or closely related that can be used to support co-reference resolution and entity linking. For Semantic Web data, consolidating instances can be as simple as relating instances using owl: sameAs, as is the case in...

    Provided By University of Mary Washington

  • White Papers // Jul 2012

    Gaussian Wiretap Channel With a Batteryless Energy Harvesting Transmitter

    The authors study the Gaussian wiretap channel with an energy harvesting transmitter which does not have a battery to save energy. In the absence of a battery, the necessary transmission energy is maintained by an i.i.d. energy arrival process. They observe that this channel is an instance of the state-dependent...

    Provided By University of Mary Washington

  • White Papers // Jul 2012

    Gaussian Wiretap Channel With an Amplitude Constraint

    The authors consider the Gaussian wiretap channel with an amplitude constraint, i.e., a peak power constraint, on the channel input. They show that the entire rate-equivocation region of the Gaussian wiretap channel with an amplitude constraint is obtained by discrete input distributions with finite support. They prove this result by...

    Provided By University of Mary Washington

  • White Papers // Jul 2012

    A Domain Independent Framework for Extracting Linked Semantic Data From Tables

    Vast amounts of information is encoded in tables found in documents, on the Web, and in spreadsheets or databases. Integrating or searching over this information benefits from understanding its intended meaning and making it explicit in a semantic representation language like RDF. Most current approaches to generating Semantic Web representations...

    Provided By University of Mary Washington

  • White Papers // Apr 2012

    Privacy Control in Smart Phones Using Semantically Rich Reasoning and Context Modeling

    The authors present their ongoing work on user data and contextual privacy preservation in mobile devices through semantic reasoning. Recent advances in context modeling, tracking and collaborative localization have led to the emergence of a new class of Smartphone applications that can access and share embedded sensor data. Unfortunately, this...

    Provided By University of Mary Washington

  • White Papers // Sep 2012

    Cluster-Based Instance Consolidation for Subsequent Matching

    Instance consolidation is a way to merge instances that are thought to be the same or closely related that can be used to support co-reference resolution and entity linking. For Semantic Web data, consolidating instances can be as simple as relating instances using owl: sameAs, as is the case in...

    Provided By University of Mary Washington

  • White Papers // Jul 2012

    A Policy-Based Approach to Smart Cloud Services

    Virtualized service models are now emerging and redefining the way information technology is delivered. Managing these services efficiently over the cloud is an open challenge. The authors are developing a policy-based integrated framework for automating acquisition and consumption of Cloud services. They have developed a tool, Smart Cloud Services tool,...

    Provided By University of Mary Washington

  • White Papers // Jul 2012

    A Domain Independent Framework for Extracting Linked Semantic Data From Tables

    Vast amounts of information is encoded in tables found in documents, on the Web, and in spreadsheets or databases. Integrating or searching over this information benefits from understanding its intended meaning and making it explicit in a semantic representation language like RDF. Most current approaches to generating Semantic Web representations...

    Provided By University of Mary Washington

  • White Papers // Apr 2012

    A Knowledge-Based Approach to Intrusion Detection Modeling

    Current state of the art Intrusion Detection and Prevention Systems (IDPS) are signature-based systems that detect threats and vulnerabilities by cross-referencing the threat or vulnerability signatures in their databases. These systems are incapable of taking advantage of heterogeneous data sources for analysis of system activities for threat detection. This paper...

    Provided By University of Mary Washington

  • White Papers // Feb 2012

    A Policy Driven Semantic Approach to Data Usage Management

    As the amount of information available on the web has increased, several privacy and security issues around the use of such information have arisen. Government (and private) entities are able to gather and analyze data from several disparate sources with ease. This ability to do large scale analytics of publicly...

    Provided By University of Mary Washington

  • White Papers // Oct 2012

    Multi-View Constrained Clustering with an Incomplete Mapping Between Views

    Multi-view learning algorithms typically assume a complete bipartite map-ping between the different views in order to exchange information during the learning process. However, many applications provide only a partial mapping between the views, creating a challenge for current methods. To address this problem, the authors propose a multi-view algorithm based...

    Provided By University of Mary Washington

  • White Papers // Sep 2012

    Secure Degrees of Freedom of One-Hop Wireless Networks

    The authors study the secure Degrees of Freedom (DoF) of one-hop wireless networks by considering four fundamental wireless network structures: Gaussian wiretap channel, Gaussian broadcast channel with confidential messages, Gaussian interference channel with confidential messages, and Gaussian multiple access wiretap channel. The secrecy capacity of the canonical Gaussian wiretap channel...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Signal Reflection-Enabled Geographical Routing for Underwater Sensor Networks

    The 3-D nature of the underwater environment has made geographical-routing a popular choice in UnderWater Acoustic Sensor Networks (UW-ASNs). A geographical (geo) routing protocol works by using the position information to find the best route from a source to a destination. These algorithms, often try to minimize the Line-Of-Sight (LOS)...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Providing Location Anonymity in a Multi-Base Station Wireless Sensor Network

    Wireless Sensor Networks (WSNs) often operate in inhospitable environments to serve mission-critical and security sensitive applications that involve hostile adversaries. These adversaries are eager to disrupt the WSN operation. Given the important role that the Base-Station (BS) plays in a WSN, the adversary opts to identify the BS and determine...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Optimized Interconnection of Disjoint Wireless Sensor Network Segments Using K Mobile Data Collectors

    Due to harsh environmental conditions a Wireless Sensor Network (WSN) may suffer from large scale damage where many nodes fail simultaneously and thus the network gets partitioned into several disjoint network segments. Restoring intersegment connectivity is essential to avoid negative effects on the application. Employing Mobile Data Collectors (MDCs), which...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Optimal Frequency Selection for Energy Efficient Underwater Acoustic Networks

    The underwater acoustic channel is characterized by a path loss that is dependent on both the distance and the frequency of communication. Given this dependence, it has been previously demonstrated that for a given communication distance, there is an optimal operating frequency, where conditions for signal propagation and noise are...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Energy-Efficient Cellular Network Operation Via Base Station Cooperation

    The rising cost of energy and increased environmental awareness has sparked a keen interest in the development and deployment of energy-efficient communication technologies. The energy efficiency of cellular networks can be increased significantly by selectively switching off some of the Base Stations (BSs) during periods of low traffic load. In...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Indirect Reciprocity Game Modelling for Secure Wireless Networks

    The authors formulate the wireless security problem as an indirect reciprocity game, and propose a security mechanism that applies the indirect reciprocity principle to suppress attacks in wireless networks. In this system, a large number of nodes cooperate to reject the network access requests from attackers during the punishment periods....

    Provided By University of Mary Washington

  • White Papers // May 2012

    Network Connectivity With Heterogeneous Mobility

    The authors study the issue of Mobile Wireless Network (MWN) connectivity. In particular, they investigate the smallest communication or transmission range of the nodes necessary for connectivity of MWNs, which they call the Critical Transmission Range (CTR). Unlike many of existing studies, however, the mobilities of the nodes are not...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Error Performances of Multiple Access System Using Analog Network Coding

    In this paper, the authors study the error performances of the multiple access system using Analog Network Coding (ANC), where all the users broadcast their data to the relays and destination simultaneously in the first phase, and the relays forward the source messages that have been mixed in the air...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Cooperation Stimulation in Cooperative Communications: An Indirect Reciprocity Game

    The viability of cooperative communications largely depends on the willingness of users to help. However, in future wireless networks where users are rational and pursue different objectives, they will not help relay information for others unless this can improve their own utilities. Therefore, it is very important to study the...

    Provided By University of Mary Washington

  • White Papers // May 2012

    Vehicular Networking for Intelligent and Autonomous Traffic Management

    Traffic congestion has become a daily problem that most people suffer. This not only impacts the productivity of the population but also poses a safety risk. Most of the technologies for intelligent highways focus on safety measures and increased driver awareness, and expect a centralized management for the traffic flow....

    Provided By University of Mary Washington

  • White Papers // May 2012

    A Cheat-Proof Game Theoretic Demand Response Scheme for Smart Grids

    While demand response has achieved promising results on making the power grid more efficient and reliable, the additional dynamics and flexibility brought by demand response also increase the uncertainty and complexity of the centralized load forecast. In this paper, the authors propose a game theoretic demand response scheme that can...

    Provided By University of Mary Washington

  • White Papers // Aug 2011

    Secure Lossy Transmission of Vector Gaussian Sources

    The authors explain the secure lossy transmission of a vector Gaussian source to a legitimate user in the presence of an eavesdropper, where both the legitimate user and the eavesdropper have vector Gaussian side information. The aim of the transmitter is to describe the source to the legitimate user in...

    Provided By University of Mary Washington

  • White Papers // Dec 2012

    Runtime Optimizations for Prediction with Tree-Based Models

    Tree-based models have proven to be an effective solution for web ranking as well as other problems in diverse domains. This paper focuses on optimizing the runtime performance of applying such models to make predictions, given an already trained model. Although exceedingly simple conceptually, most implementations of tree-based models do...

    Provided By University of Mary Washington

  • White Papers // May 2012

    A Binary Classification Framework for Two-Stage Multiple Kernel Learning

    With the advent of kernel methods, automating the task of specifying a suitable kernel has become increasingly important. In this context, the Multiple Kernel Learning (MKL) problem of finding a combination of pre-specified base kernels that is suitable for the task at hand has received significant attention from researchers. In...

    Provided By University of Mary Washington

  • White Papers // Nov 2008

    On Secure Broadcasting

    The authors study the security of communication between a single transmitter and multiple receivers in a broadcast channel in the presence of an eavesdropper. They consider several special classes of channels. As the first model, they consider the degraded multi-receiver wiretap channel where the legitimate receivers exhibit a degradedness order...

    Provided By University of Mary Washington

  • White Papers // Sep 2008

    Delay-Minimal Transmission for Average Power Constrained Multi-Access Communications

    The authors investigate the problem of minimizing the overall transmission delay of packets in a multi-access wireless communication system, where the transmitters have average power constraints. They use a multi-dimensional Markov chain to model the Medium Access Control (MAC) layer behavior. The state of the Markov chain represents current queue...

    Provided By University of Mary Washington

  • White Papers // Jan 2013

    An Outer Bound for Multiple Access Channels with Correlated Sources

    The capacity region of the multiple access channel with correlated sources remains an open problem. Cover, El Gamal and Salehi gave an achievable region in the form of single-letter entropy and mutual information expressions, without a single-letter converse. Cover, El Gamal and Salehi also suggested a converse in terms of...

    Provided By University of Mary Washington

  • White Papers // Feb 2010

    Transmission Completion Time Minimization in an Energy Harvesting System

    The authors consider the transmission completion time minimization problem in a single-user energy harvesting wireless communication system. In this system, both the data packets and the harvested energy are modeled to arrive at the source node randomly. Their goal is to adaptively change the transmission rate according to the traffic...

    Provided By University of Mary Washington

  • White Papers // Feb 2010

    On Gaussian MIMO Compound Wiretap Channels

    The authors study the two-user one-eavesdropper discrete memoryless compound wiretap channel, where the transmitter sends a common confidential message to both users, which needs to be kept perfectly secret from the eavesdropper. They provide a new achievable secrecy rate which is shown to be potentially better than the best known...

    Provided By University of Mary Washington

  • White Papers // Feb 2012

    Deaf Cooperation for Secrecy with a Multi-Antenna Helper

    In this paper, the authors investigate the roles of Cooperative Jamming (CJ) and Noise Forwarding (NF) in improving the achievable secrecy rates of a Gaussian WireTap channel (GWT) when the helper node is equipped with multiple antennas. They decompose the channel from the helper to the eavesdropper into two orthogonal...

    Provided By University of Mary Washington

  • White Papers // Feb 2013

    Secure Degrees of Freedom of the Gaussian Wiretap Channel With Helpers and No Eavesdropper CSI: Blind Cooperative Jamming

    Wyner introduced the wiretap channel in which a legitimate transmitter wants to have secure communications with a legitimate receiver in the presence of an eavesdropper, and determined its capacity-equivocation region for the degraded case. Csiszar and Korner extended this result to the general, not necessarily degraded, wiretap channel. Leung-Yan-Cheong and...

    Provided By University of Mary Washington

  • White Papers // Sep 2011

    Deaf Cooperation for Secrecy in Multiple-Relay Networks

    In this paper, the authors investigate the roles of Cooperative Jamming (CJ) and Noise Forwarding (NF) in improving the achievable secrecy rates of a Gaussian WireTap channel (GWT). In particular, they study the role of a deaf helper in confusing the eavesdropper in a GWT channel by either transmitting white...

    Provided By University of Mary Washington

  • White Papers // Feb 2009

    On the Capacity Region of the Gaussian Multiple Access Channel with Noisy Feedback

    The authors provide a new outer bound on the capacity region of the two-user Gaussian Multiple Access Channel (MAC) with AWGN-corrupted feedback. Their outer bound is based on the idea of dependence balance due to Hekstra and Willems. Evaluating their outer bound is non-trivial as it involves taking a union...

    Provided By University of Mary Washington

  • White Papers // Feb 2009

    Ergodic Secrecy Capacity Region of the Fading Broadcast Channel

    The authors consider the fading broadcast channel from a secrecy point of view. In this channel, each user views the other user as an eavesdropper, and wants to keep its information as secret from the other user as possible. First, they consider a more general channel model which consists of...

    Provided By University of Mary Washington

  • White Papers // May 2011

    Secrecy Games on the One-Sided Interference Channel

    In this paper, the authors study the two-user one-sided interference channel with confidential messages. In this interference channel, in addition to the usual selfishness of the users, the relationship between the two pairs of users is further adversarial in the sense of both receivers' desires to eavesdrop on the communication...

    Provided By University of Mary Washington

  • White Papers // May 2012

    An Outer Bound for the Vector Gaussian CEO Problem

    The authors study the vector Gaussian CEO problem, and provide an outer bound for its rate-distortion region. They obtain their outer bound by evaluating an outer bound for the multi-terminal source coding problem by means of a technique relying on the de Bruijn identity and the properties of the Fisher...

    Provided By University of Mary Washington

  • White Papers // May 2012

    On the Sum Secure Degrees of Freedom of Two-Unicast Layered Wireless Networks

    The authors consider a two-unicast layered network where two transmitters wish to have reliable and secure communication with their respective receivers simultaneously, by utilizing a layered network between the transmitters and receivers. The single-layer version of this network is an interference channel, whose capacity is unknown in general; it is...

    Provided By University of Mary Washington

  • White Papers // Dec 2008

    Capacity Bounds for the Gaussian Interference Channel with Transmitter Cooperation

    The authors obtain a new outer bound on the capacity region of the two-user Interference Channel with Generalized Feedback (IC-GF). This outer bound is based on the idea of dependence balance which was proposed by Hekstra and Willems. They explicitly evaluate their outer bound for the Gaussian IC with User-Cooperation...

    Provided By University of Mary Washington

  • White Papers // Jun 2010

    Transmission of Common, Public and Confidential Messages in Broadcast Channels with Multiple Antennas

    The authors study the Gaussian Multiple-Input Multiple-Output (MIMO) wiretap channel, which consists of a transmitter, a legitimate user, and an eavesdropper. In this channel, the transmitter sends a common message to both the legitimate user and the eavesdropper. Moreover, the legitimate user receives a private message, which is desired to...

    Provided By University of Mary Washington

  • White Papers // Jun 2009

    Performance Studies for Multithreading in Matlab With Usage Instructions on HPC

    This report explores the use of multiple computational cores by multithreading in the software package Matlab on a compute node with two dual-core AMD Opteron processors. After testing the built-in functions of Matlab for a small test problem, the authors consider a classical test problem resulting from a finite difference...

    Provided By University of Mary Washington

  • White Papers // May 2013

    An Implementation of Binomial Method of Option Pricing using Parallel Computing

    The Binomial method of option pricing is based on iterating over discounted option payoffs in a recursive fashion to calculate the present value of an option. Implementing the Binomial method to exploit the resources of a parallel computing cluster is non-trivial as the method is not easily parallelizable. The authors...

    Provided By University of Mary Washington

  • White Papers // Sep 2008

    Compact Signatures for Network Coding

    Network coding offers increased throughput and improved robustness to random faults in completely decentralized networks. Since it does not require centralized control, network coding has been suggested for routing packets in ad-hoc networks, for content distribution in P2P file systems, and for improving the efficiency of large-scale data dissemination over...

    Provided By University of Mary Washington