University of California

Displaying 281-320 of 662 results

  • White Papers // Sep 2010

    Line and Lattice Networks Under Deterministic Interference Models

    Capacity bounds are compared for four different deterministic models of wireless networks, representing four different ways of handling broadcast and superposition in the physical layer. In particular, the transport capacity under a multiple unicast traffic pattern is studied for a one-dimensional network of regularly spaced nodes on a line and...

    Provided By University of California

  • White Papers // Sep 2010

    The Case for Using Traffic Forecasting in Schedule-Based Channel Access

    In this paper, the authors explore the idea of using traffic forecasting to improve the delay performance of a schedule-based medium access control protocol. Schedule-based channel access has been shown to utilize network and energy resources efficiently but is often hindered by the extra delay that scheduling introduces. They explore...

    Provided By University of California

  • White Papers // Sep 2010

    Static Analysis for Detecting Taint-Style Vulnerabilities in Web Applications

    The number and the importance of web applications have increased rapidly over the last years. At the same time, the quantity and impact of security vulnerabilities in such applications have grown as well. Since manual code reviews are time-consuming, error-prone and costly, the need for automated solutions has become evident....

    Provided By University of California

  • White Papers // Sep 2010

    A System for Managing Physical Data in Buildings

    In order to reduce building energy consumption, the authors need a global, accurate view of the building. Many modern buildings have a sensing infrastructure that can be used to do fine-grained accounting and understand the complex interactions between systems and spaces. However, through the experience with an active, campus-wide Building...

    Provided By University of California

  • White Papers // Sep 2010

    FATE and DESTINI: A Framework for Cloud Recovery Testing

    As the cloud era begins and failures become commonplace, the fate and destiny of availability, reliability and performance are in the hands of failure recovery. Unfortunately, recovery problems still take place, causing downtimes, data loss, and many other problems. The authors propose a new testing framework for cloud recovery: FATE...

    Provided By University of California

  • White Papers // Sep 2010

    Decentralized Multi-Armed Bandit With Imperfect Observations

    The authors consider decentralized multi-armed bandit problems with multiple distributed players. At each time, each player chooses one of the N independent arms with unknown reward statistics to play. Players do not exchange information regarding their observations or actions. A collision occurs when multiple players choose the same arm. In...

    Provided By University of California

  • White Papers // Sep 2010

    Active Cloud DB: A RESTful Software-as-a-Service for Language Agnostic Access to Distributed Datastores

    In this paper, the authors present Active Cloud DB, an open source Software-as-a-Service (SaaS) application that allows for RESTful access to cloud-based distributed datastore technologies that implement the Google Datastore API. They implement Active Cloud DB as a Google App Engine application that they employ to expose the Google App...

    Provided By University of California

  • White Papers // Sep 2010

    Cooperative Jamming and Power Allocation for Wireless Relay Networks in Presence of Eavesdropper

    Relying on physical layer security is an attractive alternative of utilizing cryptographic algorithms at upper layers of protocol stack for secure communications. In this paper, the authors consider a two-hop wireless relay network in the presence of an eavesdropper. Their scenario of interest spans over a four-node network model including...

    Provided By University of California

  • White Papers // Sep 2010

    Identifying BGP Routing Table Transfers

    BGP routing updates collected by monitoring projects such as RouteViews and RIPE have been a vital source to the understanding of the global routing system. However the collected BGP data contains both the updates generated by actual route changes, and the updates of BGP routing table transfers resulted from BGP...

    Provided By University of California

  • White Papers // Sep 2010

    Urban-X: Towards Distributed Channel Assignment in Cognitive Multi-Radio Mesh Networks

    Researches about multi-radio mesh networks have mostly focused on channel allocation under internal interference. However, the deployment of WMNs in unlicensed bands of dense urban areas imposes many challenges regarding co-existence with residential access points. In this paper, the authors propose Urban-X, which is a first attempt towards a new...

    Provided By University of California

  • White Papers // Sep 2010

    Copperhead: Compiling an Embedded Data Parallel Language

    Modern parallel microprocessors deliver high performance on applications that expose substantial fine-grained data parallelism. Although data parallelism is widely available in many computations, implementing data parallel algorithms in low-level languages is often an unnecessarily difficult task. The characteristics of parallel microprocessors and the limitations of current programming methodologies motivate the...

    Provided By University of California

  • White Papers // Sep 2010

    Impulsive Systems Triggered by Superposed Renewal Processes

    The authors consider impulsive systems with several reset maps triggered by independent renewal processes, i.e., the intervals between jumps associated with a given reset map are identically distributed and independent of the other jump intervals. Considering linear dynamic and reset maps, they establish that mean exponential stability is equivalent to...

    Provided By University of California

  • White Papers // Sep 2010

    Streaming Satellite Data to Cloud Workflows for On-Demand Computing of Environmental Products

    Environmental data arriving constantly from satellites and weather stations are used to compute weather coefficients that are essential for agriculture and viticulture. For example, the reference evapotranspiration (ET0) coefficient, overlaid on regional maps, is provided each day by the California Department of Water Resources to local farmers and turf managers...

    Provided By University of California

  • White Papers // Sep 2010

    L2-Induced Gains of Switched Systems and Classes of Switching Signals

    This paper addresses the L2-induced gain analysis for switched linear systems. The authors exploit non-conservative necessary and sufficient conditions for the induced gain to lie below a prescribed positive constant and discuss on the induced gains of switched systems obtained for different classes of switching signals, which distinct regularity assumptions...

    Provided By University of California

  • White Papers // Sep 2010

    Toward an Error Handling Mechanism for Timing Errors With Java Pathfinder and Ptolemy II

    Designing effective error handling systems in an embedded software system is essential for acceptable and reliable functionality in cases of errors and for the recovery from faults. Errors in the error handling system can cause catastrophic failures of the software, lead to mission failures and can endanger human life. The...

    Provided By University of California

  • White Papers // Sep 2010

    Toward Automated Detection of Logic Vulnerabilities InWeb Applications

    Web applications are the most common way to make services and data available on the Internet. Unfortunately, with the increase in the number and complexity of these applications, there has also been an increase in the number and complexity of vulnerabilities. Current techniques to identify security problems in web applications...

    Provided By University of California

  • White Papers // Sep 2010

    Extended H-Index Parameterized Data Structures for Computing Dynamic Subgraph Statistics

    The authors present techniques for maintaining subgraph frequencies in a dynamic graph, using data structures that are parameterized in terms of h, the h-index of the graph. The methods extend previous results of Eppstein and Spiro for maintaining statistics for undirected subgraphs of size three to directed subgraphs and to...

    Provided By University of California

  • White Papers // Sep 2010

    Linear-Complexity Private Set Intersection Protocols Secure in Malicious Model

    Private Set Intersection (PSI) protocols allow one party ("Client") to compute an intersection of its input set with that of another party ("Server"), such that the client learns nothing other than the set intersection and the server learns nothing beyond client input size. Prior work yielded a range of PSI...

    Provided By University of California

  • White Papers // Sep 2010

    A Case for Opportunistic Embedded Sensing in Presence of Hardware Power Variability

    The system lifetime gains provided by the various power management techniques in embedded sensing systems are a strong function of the active and sleep mode power consumption of the underlying hardware platform. However, power consumption characteristics of hardware platforms exhibit high variability across different instances of the platform, diverse ambient...

    Provided By University of California

  • White Papers // Sep 2010

    Tweakable Block Ciphers

    A common trend in applications of block ciphers over the past decades has been to employ block ciphers as one piece of a "Mode of operation" - possibly, a way to make a secure symmetric-key cryptosystem, but more generally, any cryptographic application. Most of the time, these modes of operation...

    Provided By University of California

  • White Papers // Sep 2010

    Quality Tradeoffs in Object Tracking With Duty-Cycled Sensor Networks

    Extending the lifetime of wireless sensor networks requires energy-conserving operations such as duty-cycling. However, such operations may impact the effectiveness of high-fidelity real-time sensing tasks, such as object tracking, which require high accuracy and short response times. In this paper, the authors quantify the influence of different duty-cycle schemes on...

    Provided By University of California

  • White Papers // Aug 2010

    The Design of a Reliable Reputation System

    Next generation Web 2.0 communities and distributed P2P systems rely on the cooperation of diverse user populations spread across numerous administrative and security domains. Zero accountability via anonymous online identities and divergent interests result in selfish behavior that can disrupt or manipulate networks for personal gain. While "Reputation systems" are...

    Provided By University of California

  • White Papers // Aug 2010

    Inter-Socket Victim Cacheing for Platform Power Reduction

    On a multi-socket architecture with load below peak, as is often the case in a server installation, it is common to consolidate load onto fewer sockets to save processor power. However, this can increase main memory power consumption due to the decreased total cache space. This paper describes inter-socket victim...

    Provided By University of California

  • White Papers // Aug 2010

    Provenance in ORCHESTRA

    Sharing structured data today requires agreeing on a standard schema, then mapping and cleaning all of the data to achieve a single queriable mediated instance. However, for settings in which structured data is collaboratively authored by a large community, such as in the sciences, there is seldom consensus about how...

    Provided By University of California

  • White Papers // Aug 2010

    Why Johnny Can't Pentest: An Analysis of Black-Box Web Vulnerability Scanners

    Black-box web vulnerability scanners are a class of tools that can be used to identify security issues in web applications. These tools are often marketed as "Point-and-click pentesting" tools that automatically evaluate the security of web applications with little or no human support. These tools access a web application in...

    Provided By University of California

  • White Papers // Aug 2010

    VAPR: Void Aware Pressure Routing Protocol

    UnderWater Acoustic Sensor Networks (UW-ASNs) have lately been suggested as a potent means of supporting aquatic applications ranging from environmental monitoring to intrusion detection. A bevy of mobile sensor nodes each equipped with a variety of sensors and a low bandwidth acoustic modem (e.g. Drogues) can be deployed the region...

    Provided By University of California

  • White Papers // Aug 2010

    CEO: A Cloud Epistasis computing Model in GWAS

    The 1000 Genome project has made available a large number of Single Nucleotide Polymorphisms (SNPs) for Genome-Wide Association Studies (GWAS). However, the large number of SNPs has also rendered the discovery of epistatic interactions of SNPs computationally expensive. Parallelizing the computation offers a promising solution. This paper proposes a Cloud-based...

    Provided By University of California

  • White Papers // Aug 2010

    Two-Handed Marking Menus for Multi-Touch Devices

    The authors investigate multi-stroke marking menus for multi-touch devices and they show that using two hands can improve performance. They present two new two-handed multi-stroke marking menu variants in which users either draw strokes with both hands simultaneously or alternate strokes between hands. In a pair of studies they find...

    Provided By University of California

  • White Papers // Aug 2010

    A Model-Based Process for Evaluating Cluster Building Blocks

    Traditional servers account for more than 1.5% of the US electricity use though spend their lives largely underutilized or idle. Because a large portion of power in a data center is due directly or indirectly to servers, power savings in a data center environment can be achieved simply by using...

    Provided By University of California

  • White Papers // Aug 2010

    Multi-Modal Modeling of Urban Mobility

    Design and efficacy of a routing protocol for mobile ad-hoc networks strongly depends on the underlying mobility pattern of the mobile nodes. Counter to the perception of mobility being random in time and space, the authors show that spatial modality is a key trait of human mobility. Most of the...

    Provided By University of California

  • White Papers // Aug 2010

    Automating Data Center Operations Using Machine Learning

    Today's Internet data-centers run many complex and large-scale Web applications that are very difficult to manage. The main challenges are understanding user workloads and application performance, and quickly identifying and resolving performance problems. Statistical Machine Learning (SML) provides a methodology for quickly processing the large quantities of monitoring data generated...

    Provided By University of California

  • White Papers // Aug 2010

    Results and Techniques in Multiuser Information Theory

    In this dissertation the authors develop new techniques and apply them to prove new results in multiuser information theory. In the first part of the dissertation, they introduce the "Potential function method," and apply it to prove converses for a series of multi-terminal network capacity problems. In the second part...

    Provided By University of California

  • White Papers // Aug 2010

    Interactive Visual Analysis of Hierarchical Enterprise Data

    In this paper, the authors present an interactive visual technique for analyzing and understanding hierarchical data, which they have applied to analyzing a corpus of technical reports produced by a corporate research laboratory. The analysis begins by selecting a known entity, such as a topic, a report, or a person,...

    Provided By University of California

  • White Papers // Aug 2010

    Quantitative Evaluation of Secure Network Coding

    Network coding has gained significant attention by improving throughput and reliability in disruptive MANETs. Yet, it is vulnerable to attacks from malicious nodes. In order to prevent this attack, the authors have explored the use of secure network coding schemes based on homomorphic properties of cryptographic systems. While the method...

    Provided By University of California

  • White Papers // Aug 2010

    Bayesian Inference for Queueing Networks and Modeling of Internet Services

    Modern Internet services, such as those at Google, Yahoo!, and Amazon, handle billions of requests per day on clusters of thousands of computers. Because these services operate under strict performance requirements, a statistical understanding of their performance is of great practical interest. Such services are modeled by networks of queues,...

    Provided By University of California

  • White Papers // Aug 2010

    System Problem Detection by Mining Console Logs

    The console logs generated by an application contain information that the developers believed would be useful in debugging or monitoring the application. Despite the ubiquity and large size of these logs, they are rarely exploited because they are not readily machine-parsable. The authors propose a fully automatic methodology for mining...

    Provided By University of California

  • White Papers // Aug 2010

    Towards Cooperative Grids: Sensor/Actuator Networks for Renewables Integration

    Faced with an uncertain path forward to Renewables Portfolio Standard (RPS) goals and the high cost of energy storage, the authors believe that deep demand side management must be a central strategy to achieve widespread penetration of renewable energy sources. They examine the variability of wind as a source of...

    Provided By University of California

  • White Papers // Jul 2010

    Code Generation for Embedded Java With Ptolemy

    Code generation from models is the ultimate goal of model-based design. For real-time systems the generated code must be analyzable for the worst-case execution time (WCET). This paper evaluates Java code generation from Ptolemy II for embedded real-time Java. The target system is the time-predictable Java processor JOP. The quality...

    Provided By University of California

  • White Papers // Jul 2010

    On Developing Smart Applications for VANETs: Where Are We Now? Some Insights on Technical Issues and Open Problems

    The advances in research on ad hoc networks, the availability of cheap radio interfaces (e.g. Wi-Fi) and the increasing amount of electronic devices installed in vehicles have set the path for vehicular ad hoc networks. In the past few years, Vehicular Ad hoc NETwork (VANET) research has addressed all layers,...

    Provided By University of California

  • White Papers // Jul 2010

    An Adaptive Multi-Channel P2P Video-on-Demand System Using Plug-and-Play Helpers

    They authors present a multi-channel P2P Video-on-Demand (VoD) system using "plug-and-play" helpers. Helpers are heterogeneous "micro-servers" with limited storage, bandwidth and number of users they can serve simultaneously. The proposed system has the following salient features: it minimizes the server load; it is distributed, and requires little or no maintenance...

    Provided By University of California

  • White Papers // Aug 2010

    Quantitative Evaluation of Secure Network Coding

    Network coding has gained significant attention by improving throughput and reliability in disruptive MANETs. Yet, it is vulnerable to attacks from malicious nodes. In order to prevent this attack, the authors have explored the use of secure network coding schemes based on homomorphic properties of cryptographic systems. While the method...

    Provided By University of California

  • White Papers // Aug 2010

    Multi-Modal Modeling of Urban Mobility

    Design and efficacy of a routing protocol for mobile ad-hoc networks strongly depends on the underlying mobility pattern of the mobile nodes. Counter to the perception of mobility being random in time and space, the authors show that spatial modality is a key trait of human mobility. Most of the...

    Provided By University of California

  • White Papers // Aug 2008

    Flexible and Secure Communications in an Identity-Based Coalition Environment

    In this paper, the authors consider the problem of how entities operating under distinct roots of trust in a coalition environment can flexibly and securely communicate with one another. They consider the identity-based setting, with each entity being pre-configured with a private key from a particular Trusted Authority (TA), but...

    Provided By University of California

  • White Papers // Sep 2010

    Tweakable Block Ciphers

    A common trend in applications of block ciphers over the past decades has been to employ block ciphers as one piece of a "Mode of operation" - possibly, a way to make a secure symmetric-key cryptosystem, but more generally, any cryptographic application. Most of the time, these modes of operation...

    Provided By University of California

  • White Papers // May 2011

    Exploring the Relationship BetweenWeb Application Development Tools and Security

    How should software engineers choose which tools to use to develop secure web applications? Different developers have different opinions regarding which language, framework, or vulnerability-finding tool tends to yield more secure software than another; some believe that there is no difference at all between such tools. This paper adds quantitative...

    Provided By University of California

  • White Papers // May 2011

    Phishing on Mobile Devices

    The authors assess the risk of phishing on mobile platforms. Mobile operating systems and browsers lack secure application iden-tity indicators, so the user cannot always identify whether a link has taken her to the expected application. They conduct a systematic analysis of ways in which mobile applications and web sites...

    Provided By University of California

  • White Papers // Mar 2011

    Defeating UCI: Building Stealthy and Malicious Hardware

    In previous work Hicks et al. proposed a method called Unused Circuit Identification (UCI) for detecting malicious backdoors hidden in circuits at design time. The UCI algorithm essentially looks for portions of the circuit that go unused during design-time testing and flags them as potentially malicious. In this paper, the...

    Provided By University of California

  • White Papers // Apr 2010

    Lazy Annotation for Program Testing and Verification

    The authors describe an interpolant-based approach to test generation and model checking for sequential programs. The method generates Floyd/Hoare style annotations of the program on demand, as a result of failure to achieve goals, in a manner analogous to conflict clause learning in a DPLL style SAT solver. The DPLL...

    Provided By University of California

  • White Papers // Dec 2011

    Security Primitives and Protocols for Ultra Low Power Sensor Systems

    Security requirements in sensor systems include resiliency against physical and side-channel attacks, low energy for communication, storage, and computation, and the ability to realize a variety of public-key protocols. Furthermore, primitives and protocols that enable trusted remote operation in terms of data, time, and location are essential to guarantee secure...

    Provided By University of California

  • White Papers // May 2011

    Energy Efficient E-Textile Based Portable Keyboard

    The authors have created sensor architecture, data collection and processing techniques for an E-Textile wireless keyboard. They leverage the inherent properties of E-Textiles to produce optimized architecture for energy efficient sensing. Novel techniques such as one where each sensor senses several events (activations of different keys) and each event is...

    Provided By University of California

  • White Papers // Dec 2011

    Detecting Local Events Using Global Sensing

    In order to create low power, low latency and reliable sensing systems, the authors propose a sensing strategy that identifies local events by the means of global measurements. They claim that capturing events globally, although seems against intuition, can save energy by enabling the organization of effective searching queries. To...

    Provided By University of California

  • White Papers // Sep 2011

    Robust Passive Hardware Metering

    Current hardware metering techniques, which use manifestational properties of gates for ID extraction, are weakened by the non-uniform effects of aging in conjunction with variations in temperature and supply voltage. As an Integrated Circuit (IC) ages, the manifestational properties of the gates change, and thus the ID used for hardware...

    Provided By University of California

  • White Papers // Dec 2011

    Medical Diagnostic-Based Sensor Selection

    Wearable sensing systems have facilitated a variety of applications in Wireless Health. Due to the considerable number of sensors and their constant monitoring these systems are often expensive and power hungry. Traditional approaches to sensor selection in large multi-sensory arrays attempt to alleviate these issues by removing redundant sensors while...

    Provided By University of California

  • White Papers // Dec 2011

    Nanotechnology-Based Trusted Remote Sensing

    The authors present a new nanotechnology PPUF-based architecture for trusted remote sensing. Current public physical unclonable function designs encompass complex circuits requiring high measurement accuracy and whose size slows down the authentication process. Their novel nanotechnology-based architecture ensures fast authentication through partial simulation while maintaining robust security. They authenticate over...

    Provided By University of California

  • White Papers // Feb 2011

    Securing Netlist-Level FPGA Design Through Exploiting Process Variation and Degradation

    The continuously widening gap between the Non-Recurring Engineering (NRE) and Recurring Engineering (RE) costs of producing Integrated Circuit (IC) products in the past few decades gives high incentives to unauthorized cloning and reverse-engineering of ICs. Existing IC Digital Rights Management (DRM) schemes often demands high overhead in area, power, and...

    Provided By University of California

  • White Papers // Jun 2011

    Matched Public PUF: Ultra Low Energy Security Platform

    Hardware-based Physically Unclonable Functions (PUFs) leverage intrinsic process variation of modern integrated circuits to provide interesting security solutions but either induce high storage requirements or require significant resources of at least one involved party. The authors use device aging to realize two identical unclonable modules that cannot be matched with...

    Provided By University of California

  • White Papers // Dec 2009

    Temporal Spectrum Access Scheduling for Heterogeneous Wireless Systems Coexistence

    The wireless spectrum has always been the scarce resource that creates bottlenecks in communication channels. On the other hand, the channel access scheduling has gone from coordinating homogeneous users to heterogeneous ones, as seen in the recent development of cognitive radio technologies. In this paper, the authors address the spectrum...

    Provided By University of California

  • White Papers // Sep 2009

    Stable Energy-Aware Topology Management in Ad Hoc Networks

    The efficiency of a communication network depends not only on its control protocols, but also on the underlying network topology. The authors propose a distributed topology management algorithm that constructs and maintains a backbone topology based on a Minimal Dominating Set (MDS) of the network. According to this algorithm, each...

    Provided By University of California

  • White Papers // Oct 2009

    Spectrum Access Scheduling Among Heterogeneous Wireless Systems

    The spectrum scarcity problem emerged in recent years. Spectrum access scheduling addresses challenges arising from spectrum sharing by interleaving the channel access among multiple wireless systems in a TDMA fashion. Different from cognitive radio approaches which are opportunistic and non-collaborative in general, spectrum access scheduling proactively structures and interleaves the...

    Provided By University of California

  • White Papers // Jan 2011

    Latin Square Based Channel Access Scheduling in Large-Scale WLAN Systems

    WLAN systems based on the IEEE 802.11 could contain hundreds even up to thousands of wireless access points nowadays. However, IEEE 802.11 MAC protocols, including DCF, PCF and EDCA mechanisms, are unable to meet the challenges to provide collision freedom, especially in distributed large scale WLAN systems. The authors propose...

    Provided By University of California

  • White Papers // Apr 2010

    Location Estimation for Wireless Sensor Retrieval

    Wireless sensor retrieval is importance for cost saving, data analysis and security purposes in WSNs. Finding sensors is especially challenging because both the number and locations of these sensors could be unknown. In this paper, the authors propose an online probabilistic localization algorithms that iteratively calculate the locations of multiple...

    Provided By University of California

  • White Papers // Jan 2011

    Toward a Definition of and Linguistic Support for Partial Quiescence

    The global quiescence of a distributed computation (or distributed termination detection) is an important problem. Some concurrent programming languages and systems provide global quiescence detection as a built-in feature so that programmers do not need to write special synchronization code to detect quiescence. This paper introduces Partial Quiescence (PQ), which...

    Provided By University of California

  • White Papers // May 2010

    Spark: Cluster Computing With Working Sets

    MapReduce and its variants have been highly successful in implementing large-scale data-intensive applications on commodity clusters. However, most of these systems are built around an acyclic data flow model that is not suitable for other popular applications. This paper focuses on one such class of applications: those that reuse a...

    Provided By University of California

  • White Papers // Nov 2011

    Recomputing Materialized Instances After Changes to Mappings and Data

    A major challenge faced by today's information systems is that of evolution as data usage evolves or new data resources become available. Modern organizations sometimes exchange data with one another via declarative mappings among their databases, as in data exchange and collaborative data sharing systems. Such mappings are frequently revised...

    Provided By University of California

  • White Papers // Apr 2009

    Gaming the Jammer: Is Frequency Hopping Effective ?

    Frequency hopping has been the most popularly considered approach for alleviating the effects of jamming attacks. In this paper, the authors provide a novel, measurement-driven, game theoretic framework that captures the interactions between a communication link and an adversarial jammer, possibly with multiple jamming devices, in a wireless network employing...

    Provided By University of California

  • White Papers // Sep 2009

    Verifying Ptolemy II Discrete-Event Models Using Real-Time Maude

    This paper shows how Ptolemy II Discrete-Event (DE) models can be formally analyzed using Real-Time Maude. The authors formalize in Real-Time Maude the semantics of a subset of hierarchical Ptolemy II DE models, and explain how the code generation infrastructure of Ptolemy II has been used to automatically synthesize a...

    Provided By University of California

  • White Papers // Dec 2011

    Template-Based Program Veri Cation and Program Synthesis

    Program verification is the task of automatically generating proofs for a program's compliance with a given specification. Program synthesis is the task of automatically generating a program that meets a given specification. Both program verification and program synthesis can be viewed as search problems, for proofs and programs, respectively. For...

    Provided By University of California

  • White Papers // Oct 2011

    Types for Precise Thread Interference

    The potential for unexpected interference between threads makes multi-threaded programming notoriously difficult. Programmers use a variety of synchronization idioms such as locks and barriers to restrict where interference may actually occur. Unfortunately, the resulting actual interference points are typically never documented and must be manually reconstructed as the first step...

    Provided By University of California

  • White Papers // May 2010

    Beyond Multi-Hop: Optimal Cooperation in Large Wireless Networks

    Multi-hop is the communication architecture of current wireless networks such as mesh or ad hoc networks. Packets are sent from each source to its destination via multiple point-to-point transmissions between relaying nodes. The origins of this approach are rooted in the practice of traditional wire-line networks. Today, the increasing need...

    Provided By University of California

  • White Papers // Feb 2010

    Linear Capacity Scaling in Wireless Networks: Beyond Physical Limits?

    Multi-hop is the communication architecture of current wireless networks such as mesh or ad hoc networks. Packets are sent from each source to its destination via multiple relay nodes. Each relay decodes the packets sent from the previous relay and forwards them to the next relay. Can more sophisticated cooperation...

    Provided By University of California

  • White Papers // Apr 2009

    Reliable Relaying With Uncertain Knowledge

    The motivation for this paper is to analyze the effect of information uncertainty on the design and performance of protocols. The paper considers two types of situations. The first is when different nodes in the network have bounded knowledge about what other nodes know. The second, called common knowledge about...

    Provided By University of California

  • White Papers // Aug 2009

    Utility-Maximizing Scheduling for Stochastic Processing Networks

    Stochastic Processing Networks (SPNs) model manufacturing, communication, or service systems. In such a network, service activities require parts and resources to produce other parts. Because service activities compete for resources, the scheduling in a SPN requires deciding which of a set of conflicting activities should be performed at any given...

    Provided By University of California

  • White Papers // Aug 2009

    Convergence and Stability of a Distributed CSMA Algorithm for Maximal Network Throughput

    Designing efficient scheduling algorithms is an important problem in a general class of networks with resource-sharing constraints, such as wireless networks and stochastic processing networks. The authors proposed a distributed scheduling algorithm that can achieve the maximal throughput in such networks under certain conditions. This algorithm was inspired by CSMA...

    Provided By University of California

  • White Papers // Nov 2009

    Stable and Utility-Maximizing Scheduling for Stochastic Processing Networks

    Stochastic Processing Networks (SPNs) are models of service, processing, communication, or manufacturing systems. In such a network, service activities require parts and resources to produce new parts. Thus, parts flow through a network of buffers served by activities that consume parts and produce new ones. Typically, service activities compete for...

    Provided By University of California

  • White Papers // Nov 2009

    Optimal Tradeoff Between Exposed and Hidden Nodes in Large Wireless Networks

    Wireless networks equipped with the CSMA protocol are subject to collisions due to interference. For a given interference range the authors investigate the trade-off between collisions (hidden nodes) and unused capacity (exposed nodes). They determine the optimal sensing range that maximizes throughput and critically depends on the activation rate of...

    Provided By University of California

  • White Papers // Feb 2010

    Performance Bounds of Distributed CSMA Scheduling

    CSMA-based scheduling is a recently proposed distributed scheduling algorithm that is shown to achieve the maximal throughput. Central to this algorithm is a Markov chain that produces samples from a desired distribution. In this paper, the authors discuss the relationships of the achievable throughput, queueing delay and the mixing time...

    Provided By University of California

  • White Papers // Jan 2011

    PoX: Protecting Users From Malicious Facebook Applications

    Online social networks such as Facebook, MySpace, and Orkut store large amounts of sensitive user data. While a user can legitimately assume that a social network provider adheres to strict privacy standards, the authors argue that it is unwise to trust third-party applications on these platforms in the same way....

    Provided By University of California

  • White Papers // Aug 2010

    The Design of a Reliable Reputation System

    Next generation Web 2.0 communities and distributed P2P systems rely on the cooperation of diverse user populations spread across numerous administrative and security domains. Zero accountability via anonymous online identities and divergent interests result in selfish behavior that can disrupt or manipulate networks for personal gain. While "Reputation systems" are...

    Provided By University of California

  • White Papers // Jan 2011

    Routing and Multicast in Multihop, Mobile Wireless Networks

    In this paper, the authors present a multicast protocol which builds upon a cluster based wireless network infrastructure. First, they introduce the network infrastructure which includes several innovative features such as: minimum change cluster formation; dynamic priority token access protocol, and; distributed hierarchical routing. Then, for this infrastructure they propose...

    Provided By University of California

  • White Papers // May 2011

    Maximum Damage Battery Depletion Attack in Mobile Sensor Networks

    Developing reliable security measures against outbreaks of malware will facilitate the proliferation of wireless sensing technologies. The first step toward this goal is to investigate potential attack strategies and the extent of damage they can incur. The malware at each infective node may seek to contact more susceptible nodes by...

    Provided By University of California