Stanford University

Displaying 1-40 of 483 results

  • White Papers // Sep 2014

    Password Managers: Attacks and Defenses

    The authors study the security of popular password managers and their policies on automatically filling in web passwords. They examine browser built-in password managers, mobile password managers, and 3rd party managers. They observe significant differences in auto fill policies among password managers. Several auto fill policies can lead to disastrous...

    Provided By Stanford University

  • White Papers // May 2014

    An Experimental Study of TLS Forward Secrecy Deployments

    Forward secrecy guarantees that eavesdroppers simply cannot reveal secret data of past communications. While many TLS servers have deployed the ephemeral Diffie-Hellman (DH) key exchange to support forward secrecy, most sites use weak DH parameters resulting in a false sense of security. In this paper, the authors surveyed a total...

    Provided By Stanford University

  • White Papers // Apr 2013

    A Promising Direction for Web Tracking Countermeasures

    Web tracking continues to pose a vexing policy problem. Surveys have repeatedly demonstrated substantial consumer demand for control mechanisms, and policymakers worldwide have pressed for a Do Not Track system that effectuates user preferences. At present, however, consumers are left in the lurch: existing control mechanisms and countermeasures have spotty...

    Provided By Stanford University

  • White Papers // May 2012

    Channel Capacity Under General Nonuniform Sampling

    This paper develops the fundamental capacity limits of a sampled analog channel under a sub-Nyquist sampling rate constraint. In particular, the authors derive the capacity of sampled analog channels over a general class of time-preserving sampling methods including irregular non-uniform sampling. Their results indicate that the optimal sampling structures extract...

    Provided By Stanford University

  • White Papers // May 2012

    EyeQ: Practical Network Performance Isolation for the Multi-Tenant Cloud

    The shared multi-tenant nature of the cloud has raised serious concerns about its security and performance for high valued services. Of many shared resources like CPU, memory, etc., the network is pivotal for distributed applications. Benign, or perhaps malicious traffic interference between tenants can cause significant performance degradation that hurts...

    Provided By Stanford University

  • White Papers // Apr 2012

    Who Killed My Battery: Analyzing Mobile Browser Energy Consumption

    Despite the growing popularity of mobile web browsing, the energy consumed by a phone browser while surfing the web is poorly understood. The authors present an infrastructure for measuring the precise energy used by a mobile browser to render web pages. They then measure the energy needed to render financial,...

    Provided By Stanford University

  • White Papers // Apr 2012

    Shannon Meets Nyquist: Capacity Limits of Sampled Analog Channels

    The authors explore two fundamental questions at the intersection of sampling theory and information theory: how is channel capacity affected by sampling below the channel's Nyquist rate, and what sub-Nyquist sampling strategy should be employed to maximize capacity. In particular, they first derive the capacity of sampled analog channels for...

    Provided By Stanford University

  • White Papers // Apr 2012

    Synthesis for Optimal Two-Player Decentralized Control Over TCP Erasure Channels With State Feedback

    Recent advances in communication networks and VLSI have made it possible to provide services remotely. In fact, an increasing number of current services and future deployments, such as distributed database management, grid computing, and the smart grid, are now being built over the cloud, making it inevitable that the control,...

    Provided By Stanford University

  • White Papers // Apr 2012

    Coding Strategies for a Class of Decentralized Control Problems With Limited Communication

    The authors propose a large class of decentralized control problems with non-classical information structure for which a coding strategy is optimal. This class is a generalized version of the hats problem with statistically dependent hat colors where implicit communication via action is allowed. They propose a sufficient condition on the...

    Provided By Stanford University

  • White Papers // Mar 2012

    Optimal Cooperative Control of Dynamically Decoupled Systems

    The authors consider optimal cooperative control problems where multiple dynamically decoupled players cooperate to optimize a coupled objective under limited communication between each player. They present the explicit optimal control in terms of the solutions to a series of Riccati equations, therefore it can be computed in a distributed manner...

    Provided By Stanford University

  • White Papers // Mar 2012

    Achievable Error Exponents in the Gaussian Channel With Rate-Limited Feedback

    The authors investigate the achievable error probability in communication over an AWGN discrete time memoryless channel with noiseless delay-less rate-limited feedback. For the case where the feedback rate RFB is lower than the data rate R transmitted over the forward channel, they show that the decay of the probability of...

    Provided By Stanford University

  • White Papers // Mar 2012

    Identity-Based Encryption Is Secure in the Quantum Random Oracle Model

    The authors give the first proof of security for an identity-based encryption scheme in the quantum random oracle model. This is the first unconditional proof of security for any scheme in this model. Their techniques are quite general and they use them to obtain (unconditional) security proofs for two random...

    Provided By Stanford University

  • White Papers // Mar 2012

    Improved Security for Linearly Homomorphic Signatures: A Generic Framework

    The authors propose a general framework that converts (ordinary) signature schemes having certain properties into linearly homomorphic signature schemes, i.e., schemes that allow authentication of linear functions on signed data. The security of the homomorphic scheme follows from the same computational assumption as is used to prove security of the...

    Provided By Stanford University

  • White Papers // Feb 2012

    Header Space Analysis: Static Checking for Networks

    Today's networks typically carry or deploy dozens of protocols and mechanisms simultaneously such as MPLS, NAT, ACLs and route redistribution. Even when individual protocols function correctly, failures can arise from the complex interactions of their aggregate, requiring network administrators to be masters of detail. The authors' goal is to automatically...

    Provided By Stanford University

  • White Papers // Feb 2012

    Less is More: Trading a Little Bandwidth for Ultra-Low Latency in the Data Center

    Traditional measures of network goodness - goodput, quality of service, fairness - are expressed in terms of bandwidth. Network latency has rarely been a primary concern because delivering the highest level of bandwidth essentially entails driving up latency - at the mean and, especially, at the tail. Recently, however, there...

    Provided By Stanford University

  • White Papers // Jan 2012

    Initial Thoughts on Custom Network Processing Via Waypoint Services

    Network operators want additional functionality from the networks they manage. The current approach to add functionality is to deploy middleboxes. Unfortunately middle-boxes raise concerns regarding robustness, correctness, and efficiency due to their need to be deployed at chokepoints. This paper provides some initial thoughts for solving the middlebox problem in...

    Provided By Stanford University

  • White Papers // Jan 2012

    SCD: A Scalable Coherence Directory With Flexible Sharer Set Encoding

    Large-scale CMPs with hundreds of cores require a directory-based protocol to maintain cache coherence. However, previously proposed coherence directories are hard to scale beyond tens of cores, requiring either excessive area or energy, complex hierarchical protocols, or inexact representations of sharer sets that increase coherence traffic and degrade performance. The...

    Provided By Stanford University

  • White Papers // Jan 2012

    Network Congestion Avoidance Through Speculative Reservation

    Congestion caused by hot-spot traffic can significantly degrade the performance of a computer network. In this paper, the authors present the Speculative Reservation Protocol (SRP), a new network congestion control mechanism that relieves the effect of hot-spot traffic in high bandwidth, low latency, lossless computer networks. Compared to existing congestion...

    Provided By Stanford University

  • White Papers // Jan 2012

    Service Differentiation in the Internet to Support Multimedia Traffic

    The current best-effort infrastructure in the Internet lacks key characteristics in terms of delay, jitter, and loss, which are required for multimedia applications (voice, video, and data). Recently, significant progress has been made toward specifying the service differentiation to be provided in the Internet for supporting multimedia applications. In this...

    Provided By Stanford University

  • White Papers // Jan 2012

    A Methodology for Mapping Multiple Use-Cases Onto Networks on Chips

    A communication-centric design approach, Networks on Chips (NoCs), has emerged as the design paradigm for designing a scalable communication infrastructure for future Systems on Chips (SoCs). As technology advances, the number of applications or use-cases integrated on a single chip increases rapidly. The different use-cases of the SoC have different...

    Provided By Stanford University

  • White Papers // Jan 2012

    Mapping and Configuration Methods for Multi-Use-Case Networks on Chips

    To provide a scalable communication infrastructure for Systems on Chips (SoCs), Networks on Chips (NoCs), a communication centric design paradigm is needed. To be cost effective, SoCs are often programmable and integrate several different applications or use-cases on to the same chip. For the SoC platform to support the different...

    Provided By Stanford University

  • White Papers // Jan 2012

    The Role of SNR in Achieving MIMO Rates in Cooperative Systems

    The authors compare the rate of a multiple-antenna relay channel to the capacity of multiple-antenna systems to characterize the cooperative capacity in different SNR regions. While it is known that in the asymptotic regime, at a high SNR or with a large number of cooperating nodes, cooperative systems lack full...

    Provided By Stanford University

  • White Papers // Jan 2012

    Architectural Support for the Stream Execution Model on General-Purpose Processors

    There has recently been much interest in stream processing, both in industry (e.g., Cell, NVIDIA G80, ATI R580) and academia (e.g., Stanford Merrimac, MIT RAW), with stream programs becoming increasingly popular for both media and more general-purpose computing. Although a special style of programming called stream programming is needed to...

    Provided By Stanford University

  • White Papers // Jan 2012

    Minimum Expected Distortion in Gaussian Layered Broadcast Coding With Successive Refinement

    A transmitter without Channel State Information (CSI) wishes to send a delay-limited Gaussian source over a slowly fading channel. The source is coded in superimposed layers, with each layer successively refining the description in the previous one. The receiver decodes the layers that are supported by the channel realization and...

    Provided By Stanford University

  • White Papers // Oct 2011

    Efficient Parallel Graph Exploration on Multi-Core CPU and GPU

    Graphs are a fundamental data representation that have been used extensively in various domains. In graph-based applications, a systematic exploration of the graph such as a Breadth-First Search (BFS) often serves as a key component in the processing of their massive data sets. In this paper, the authors present a...

    Provided By Stanford University

  • White Papers // Oct 2011

    Reduced-Dimension Multiuser Detection

    The authors present a Reduced-Dimension MultiUser Detector (RD-MUD) structure that significantly decreases the number of required correlation branches at the receiver front-end, while still achieving performance similar to that of the conventional Matched-Filter (MF) bank. RD-MUD exploits the fact that the number of active users is typically small relative to...

    Provided By Stanford University

  • White Papers // Oct 2011

    An Explicit Solution for Optimal Two-Player Decentralized Control Over TCP Erasure Channels With State Feedback

    The authors develop an optimal controller synthesis algorithm for decentralized control problems where control actions are transmitted through TCP-like erasure channels. They consider a simple two-player interconnected linear system and Bernoulli distributed erasure channels. They recast the problem to a centralized Partially Observed Markov Decision Process (POMDP) under the fictitious...

    Provided By Stanford University

  • White Papers // Sep 2011

    Decoupling Datacenter Studies From Access to Large-Scale Applications: A Modeling Approach for Storage Workloads

    The cost and power impact of suboptimal storage configurations is significant in DataCenters (DCs) as inefficiencies are aggregated over several thousand servers and represent considerable losses in capital and operating costs. Designing performance, power and cost-optimized systems requires a deep understanding of target workloads, and mechanisms to effectively model different...

    Provided By Stanford University

  • White Papers // Sep 2011

    Micro-Interactions With NFC-Enabled Mobile Phones

    This paper coins the term micro-interactions to refer to the class of small exchanges between devices that occur almost instantaneously. For example, a mobile payment using Near-Field Communication (NFC) is a micro-interaction. The arrival of NFC on smart phones makes possible a wide array of applications using micro-interactions, from sharing...

    Provided By Stanford University

  • White Papers // Aug 2011

    Buffer Sizing in 802.11 Wireless Mesh Networks

    The authors analyze the problem of buffer sizing for TCP flows in 802.11-based Wireless Mesh Networks. Their objective is to maintain high network utilization while providing low queueing delays. The problem is complicated by the time-varying capacity of the wireless channel as well as the random access mechanism of 802.11...

    Provided By Stanford University

  • White Papers // Aug 2011

    Dynamic Fine-Grain Scheduling of Pipeline Parallelism

    Scheduling pipeline-parallel programs, defined as a graph of stages that communicate explicitly through queues, is challenging. When the application is regular and the underlying architecture can guarantee predictable execution times, several techniques exist to compute highly optimized static schedules. However, these schedules do not admit run-time load balancing, so variability...

    Provided By Stanford University

  • White Papers // Aug 2011

    Black-Box Randomized Reductions in Algorithmic Mechanism Design

    The authors give the first black-box reduction from arbitrary approximation algorithms to truthful approximation mechanisms for a non-trivial class of multi-parameter problems. Specifically, they prove that every welfare-maximization problem that admits an FPTAS and can be encoded as a packing problem also admits a truthful-in-expectation randomized mechanism that is an...

    Provided By Stanford University

  • White Papers // Aug 2011

    On the Role of Mobility for Multi-Message Gossip

    In wireless ad hoc or social networks, a variety of scenarios require agents to share their individual information or resources with each other for mutual benefit. A partial list includes file sharing and rumor spreading, distributed computation and parameter estimation, and scheduling and control. Due to the huge centralization overhead...

    Provided By Stanford University

  • White Papers // Jul 2011

    Time and Cost-Efficient Modeling and Generation of Large-Scale TPCC/TPCE/TPCH Workloads

    Large-scale TPC workloads are critical for the evaluation of datacenter-scale storage systems. However, these workloads have not been previously characterized, in-depth, and modeled in a DC environment. In this paper, the authors categorize the TPC workloads into storage threads that have unique features and characterize the storage activity of TPCC,...

    Provided By Stanford University

  • White Papers // Jul 2011

    Uplink Resource Allocation for Frequency Selective Channels and Fractional Power Control in LTE

    The authors consider the allocation of spectral and power resources every subframe (1 ms) on the uplink of the Long Term Evolution (LTE) wideband Orthogonal Frequency Division Multiple Access (OFDMA) cellular network. System bandwidth is divided into multiple sub-bands. The fractional power control to manage interference is allowed to be...

    Provided By Stanford University

  • White Papers // Jun 2011

    Targeted Malleability: Homomorphic Encryption for Restricted Computations

    The authors put forward the notion of targeted malleability: given a homomorphic encryption scheme, in various scenarios they would like to restrict the homomorphic computations one can perform on encrypted data. They introduced a precise framework, generalizing the foundational notion of non-malleability introduced by Dolev, Dwork, and Naor (SICOMP '00),...

    Provided By Stanford University

  • White Papers // Jun 2011

    Parallelizing Machine Learning - Functionally

    Implementing machine learning algorithms for large data, such as the Web graph and social networks, is challenging. Even though much research has focused on making sequential algorithms more scalable, their running times continue to be prohibitively long. Meanwhile, parallelization remains a formidable challenge for this class of problems, despite frameworks...

    Provided By Stanford University

  • Webcasts // May 2011

    Innovate For America

    The presenter focuses on advancing technology and innovation to unlock national economic growth and prosperity. In this webcast, the presenter challenges students and entrepreneurs to take action now to bring innovation to the healthcare, education and government sectors.

    Provided By Stanford University

  • White Papers // May 2011

    Performance Implications of Age-Based Allocation in On-Chip-Networks

    Age-based priority is a common mechanism used to improve the fairness and Quality-of-Service (QoS) characteristics of interconnection networks. Packet age can provide remote network state information that enables routers to service packets in a globally optimal fashion. In the Network-on-Chip (NoC) setting, age-based allocation is implemented by assigning priorities to...

    Provided By Stanford University

  • Webcasts // May 2011

    The Value Of True Partnerships

    The presenters are serial entrepreneurs who believe in the fundamental power of partnerships. Empowered by working in close collaboration for years, these co-founders have started multiple companies including Patagon, Lemon Bank and Bling Nation. In this webcast, the presenters describe the value of over-communication, the decision process in making a...

    Provided By Stanford University

  • White Papers // Aug 2002

    Seasonality and Competition in Time: An Empirical Analysis of Release Date Decisions in the U.S. Motion Picture Industry

    Strong seasonality in demand, a short product life cycle, and the absence of any price competition make the release date of first-run movies one of the main strategic decisions taken by movies? distributors. The absence of good observable measures of product quality creates a difficulty in separately identifying the two...

    Provided By Stanford University

  • White Papers // Jan 2011

    Provenance for Generalized Map and Reduce Workflows

    The authors consider a class of workflows, which they call Generalized Map and Reduce Workflows (GMRWs), where input data sets are processed by an acyclic graph of map and reduce functions to produce output results. The authors show how data provenance (also sometimes called lineage) can be captured for map...

    Provided By Stanford University

  • White Papers // Oct 2010

    The SIGMOD 2010 Programming Contest a Distributed Query Engine

    The authors report on the second annual ACM SIGMOD programming contest, which consisted of building an efficient distributed query engine on top of an in-memory index. This paper is co-authored by the organizers of the competition (Cl?ment Genzmer, Pierre Senellart) and the students who built the two leading implementations (Volker...

    Provided By Stanford University

  • White Papers // Apr 2009

    Poster Abstract: Burstiness and Scaling in the Structure of Low-Power Wireless Links

    The authors observe that low-power wireless links have non-trivial time-scaling characteristics at both the physical- and link-layers. Packet Reception Rate (PRR) analysis shows that links are bursty rather than constant, i.e., their reception quality varies greatly from the overall packet reception rate at different times. Furthermore, this variation is seen...

    Provided By Stanford University

  • White Papers // Mar 2011

    Fast Crash Recovery in RAMCloud

    RAMCloud is a DRAM-based storage system that provides inexpensive durability and availability by recovering quickly after crashes, rather than storing replicas in DRAM. RAMCloud scatters backup data across hundreds or thousands of disks, and it harnesses hundreds of servers in parallel to reconstruct lost data. The system uses a log-structured...

    Provided By Stanford University

  • White Papers // Jun 2010

    Managing State for Ajax-Driven Web Components

    Ajax-driven Web applications require state to be maintained across a series of server requests related to a single Web page. This conflicts with the stateless approach used in most Web servers and makes it difficult to create modular components that use Ajax. The authors implemented and evaluated two approaches to...

    Provided By Stanford University

  • White Papers // Dec 2009

    The Case for RAMClouds: Scalable High-Performance Storage Entirely in DRAM

    Disk-oriented approaches to online storage are becoming increasingly problematic: they do not scale gracefully to meet the needs of large-scale Web applications, and improvements in disk capacity have far outstripped improvements in access latency and bandwidth. This paper argues for a new approach to datacenter storage called RAMCloud, where information...

    Provided By Stanford University

  • White Papers // Jan 2011

    The CQL Continuous Query Language: Semantic Foundations and Query Execution

    CQL, a Continuous Query Language, is supported by the STREAM prototype Data Stream Management System at Stanford. CQL is an expressive SQL-based declarative language for registering continuous queries against streams and updatable relations. The authors begin by presenting an abstract semantics that relies only on "Black box" mappings among streams...

    Provided By Stanford University

  • White Papers // May 2010

    A Natural Dynamics for Bargaining on Exchange Networks

    Bargaining networks model the behavior of a set of players that need to reach pairwise agreements for making profits. Nash bargaining solutions are special outcomes of such games that are both stable and balanced. Kleinberg and Tardos proved a sharp algorithmic characterization of such outcomes, but left open the problem...

    Provided By Stanford University

  • White Papers // Mar 2011

    Information Theoretic Limits On Learning Stochastic Differential Equations

    Consider the problem of learning the drift coefficient of a stochastic differential equation from a sample path. In this paper, the authors assume that the drift is parametrized by a high-dimensional vector. They address the question of how long the system needs to be observed in order to learn this...

    Provided By Stanford University

  • White Papers // Apr 2011

    Software or Hardware: The Future of Green Enterprise Computing

    Over the last few years, interest in "Green computing" has motivated research into energy-saving techniques for enterprise systems, from network proxies and virtual machine migration to the return of thin clients. This paper tries to answer a possibly contentious question: would the authors be better served by the embarrassingly simple...

    Provided By Stanford University

  • White Papers // May 2009

    Language-Based Isolation of Untrusted JavaScript

    Web sites that incorporate untrusted content may use browser- or language-based methods to keep such content from maliciously altering pages, stealing sensitive information, or causing other harm. The authors study language based methods for filtering and rewriting JavaScript code, using Yahoo! ADSafe and Facebook FBJS as motivating examples. They explain...

    Provided By Stanford University

  • White Papers // Sep 2009

    Isolating JavaScript With Filters, Rewriting, and Wrappers

    The authors study methods that allow web sites to safely combine JavaScript from untrusted sources. If implemented properly, filters can prevent dangerous code from loading into the execution environment, while rewriting allows greater expressiveness by inserting run-time checks. Wrapping properties of the execution environment can prevent misuse without requiring changes...

    Provided By Stanford University

  • White Papers // Feb 2010

    Kronecker Graphs: An Approach to Modeling Networks

    How can people generate realistic networks? In addition, how can they do so with a mathematically tractable model that allows for rigorous analysis of network properties? Real networks exhibit a long list of surprising properties: Heavy tails for the in- and out-degree distribution, heavy tails for the eigen-values and eigenvectors,...

    Provided By Stanford University

  • White Papers // Nov 2009

    Hard Data on Soft Errors: A Large-Scale Assessment of Real-World Error Rates in GPGPU

    Graphics Processing Units (GPUs) are gaining widespread use in computational chemistry and other scientific simulation contexts because of their huge performance advantages relative to conventional CPUs. However, the reliability of GPUs in error-intolerant applications is largely unproven. In particular, a lack of Error Checking and Correcting (ECC) capability in the...

    Provided By Stanford University

  • White Papers // Jan 2011

    Vision Paper: Enabling Privacy for the Paranoids

    P3P is a set of standards that allow corporations to declare their privacy policies. Hippocratic Databases have been proposed to implement such policies within a corporation's datastore. From an end-user individual's point of view, both of these rest on an uncomfortable philosophy of trusting corporations to protect his/her privacy. Recent...

    Provided By Stanford University

  • White Papers // Jan 2011

    Two Can Keep a Secret: A Distributed Architecture for Secure Database Services

    Recent trends towards database outsourcing, as well as concerns and laws governing data privacy, have led to great interest in enabling secure database services. Previous approaches to enabling such a service have been based on data encryption, causing a large overhead in query processing. The authors propose a new, distributed...

    Provided By Stanford University

  • White Papers // Jan 2011

    Monitoring Stream Properties for Continuous Query Processing

    The authors' query processor can be thought of as two separate components: a Query Execution component and a Property Monitoring component. Properties used by the Query Execution component, such as stream characteristics and plan operator behavior, are monitored by the Property Monitoring component. Of course, monitoring of operator behavior would...

    Provided By Stanford University

  • White Papers // Sep 2009

    Counter Braids

    In this paper the authors summarize recent work they have done on the design of a novel counter architecture for estimating flow sizes in high-speed networks, the algorithms and the theory that goes along with it. This note will provide a description of the problem and the authors' approach. It...

    Provided By Stanford University

  • White Papers // Jan 2011

    Bloom Filters: Design Innovations and Novel Applications

    Bloom filters have been very interesting in networking because they enable the high speed, low cost implementation of various hardware algorithms. The paper introduces the idea of variable-length signatures, as opposed to the current practice of using fixed-length signatures. This idea naturally enables Bloom filters to perform flow deletions, a...

    Provided By Stanford University

  • White Papers // Mar 2010

    CHOKe a Stateless Mechanism for Providing Quality of Service in the Internet

    The authors investigate the problem of providing a fair bandwidth allocation to each of n flows that share the outgoing link of a congested router. The buffer at the outgoing link is a simple FIFO, shared by packets belonging to the n flows. They devise a simple packet dropping scheme,...

    Provided By Stanford University

  • White Papers // Jan 2011

    Managing Information Leakage

    The authors explore the problem of managing information leakage by connecting two hitherto disconnected topics: Entity Resolution (ER) and Data Privacy (DP). As more of their sensitive data gets exposed to a variety of merchants, health care providers, employers, social sites and so on, there is a higher chance that...

    Provided By Stanford University

  • White Papers // Aug 2010

    Granting Silence to Avoid Wireless Collisions

    The authors describe grant-to-send, a novel collision avoidance algorithm for wireless mesh networks. Rather than announce packets it intends to send, a node using grant-to-send announces packets it expects to hear others send. They present evidence that inverting collision avoidance in this way greatly improves wireless mesh performance. Evaluating four...

    Provided By Stanford University

  • White Papers // Jul 2010

    Emerson: Scripting for Federated Virtual Worlds

    The authors introduce Emerson, a scripting language for virtual worlds that are seamless, scalable, and federated. These worlds present a number of unique challenges. Most importantly, scripts that specify the behavior of the world are distributed across many hosts and users may generate and host scripts. These constraints imply features...

    Provided By Stanford University

  • White Papers // Aug 2010

    Identifying Energy Waste Through Dense Power Sensing and Utilization Monitoring

    PowerNet is a hybrid sensor network for monitoring the power and utilization of computing systems in a large academic building. PowerNet comprises approximately 140 single-plug wired and wireless hardware power meters and 23 software sensors that monitor PCs, laptops, network switches, servers, LCD screens, and other office equipment. PowerNet has...

    Provided By Stanford University

  • White Papers // Jan 2011

    Optimal Throughput-Delay Scaling in Wireless Networks - Part II: Constant-Size Packets

    In Part I the authors characterized the optimal throughput-delay trade-off in static wireless networks as D(n) = ?(nT(n)), where D(n) and T(n) are the average packet delay and throughput in a network of n nodes, respectively. While this trade-off captures the essential network dynamics, packets need to scale down with...

    Provided By Stanford University

  • White Papers // Jan 2011

    Optimal Throughput-Delay Scaling in Wireless Networks - Part I: The Fluid Model

    A wireless network consists of a collection of nodes, each capable of transmitting to or receiving from other nodes. When a node transmits to another node, it creates interference for other nodes in its vicinity. When several nodes transmit simultaneously, a receiver can successfully receive the data sent by the...

    Provided By Stanford University

  • White Papers // Nov 2009

    Multiple Description Coding of Discrete Ergodic Sources

    The authors investigate the problem of Multiple Description (MD) coding of discrete ergodic processes. They introduce the notion of MD stationary coding, and characterize its relationship to the conventional block MD coding. In stationary coding, in addition to the two rate constraints normally considered in the MD problem, they consider...

    Provided By Stanford University

  • White Papers // Jan 2011

    Declarative Support for Sensor Data Cleaning

    Pervasive applications rely on data captured from the physical world through sensor devices. Data provided by these devices, however, tend to be unreliable. The data must, therefore, be cleaned before an application can make use of them, leading to additional complexity for application development and deployment. Here the authors present...

    Provided By Stanford University

  • White Papers // Jan 2011

    Comparing Hybrid Peer-to-Peer Systems

    Peer-to-peer systems like Napster and Gnutella have recently become popular for sharing information. In this paper, the authors study the relevant issues and tradeoffs in designing a scalable P2P system. The authors focus on a subset of P2P systems, known as "Hybrid" P2P, where some functionality is still centralized. (In...

    Provided By Stanford University

  • White Papers // Jan 2011

    Best-Effort Cache Synchronization With Source Cooperation

    In environments where exact synchronization between source data objects and cached copies is not achievable due to bandwidth or other resource constraints, stale (out-of-date) copies are permitted. It is desirable to minimize the overall divergence between source objects and cached copies by selectively refreshing modified objects. The authors call the...

    Provided By Stanford University

  • White Papers // Jan 2011

    Models and Issues in Data Stream Systems

    In this overview paper the authors motivate the need for and research issues arising from a new model of data processing. In this model, data does not take the form of persistent relations, but rather arrives in multiple, continuous, rapid, time-varying data streams. In addition to reviewing past work relevant...

    Provided By Stanford University

  • White Papers // Oct 2010

    Market Panic On Different Time-Scales

    Cross-sectional signatures of market panic were recently discussed on daily time scales in, extended here to a study of cross-sectional properties of stocks on intraday time scales. The authors confirm specific intraday patterns of dispersion and kurtosis, and find that the correlation across stocks increases in times of panic yielding...

    Provided By Stanford University

  • White Papers // Sep 2010

    National Leadership And Competing Technological Paradigms: The Globalization of Cotton Spinning, 1878-1933

    Using the records of British firms that supplied nearly 90 percent of world trade in cotton spinning machinery, the authors track the evolution and diffusion of spinning technology over more than 50 years. In contrast to scenarios in which modern technologies supplant older methods, they observe two paradigms in competitive...

    Provided By Stanford University

  • White Papers // Feb 2011

    Generating Probability Distributions Using Multivalued Stochastic Relay Circuits

    The problem of random number generation dates back to von Neumann's work in 1951. Since then, many algorithms have been developed for generating unbiased bits from complex correlated sources as well as for generating arbitrary distributions from unbiased bits. An equally interesting, but less studied aspect is the structural component...

    Provided By Stanford University

  • White Papers // Oct 2009

    Leading Project Integration

    Managing today's global projects requires focusing scarce management attention on diverse topics related to financing and delivering the project amidst cultural differences. New technology, especially modeling tools that foster project integration, offers major potential advantages, along with implementation challenges that also merit managerial attention. This paper describes the key elements...

    Provided By Stanford University

  • White Papers // Aug 2010

    Implicit Taxes On Work From Social Security And Medicare

    Implicit taxes are present in many government programs and can create substantial work disincentives. Traditionally, attention has focused on implicit taxes that are created when welfare benefits are phased out as income or wealth increases. However, the design of Social Security and Medicare also gives rise to implicit taxes, particularly...

    Provided By Stanford University

  • White Papers // Nov 2010

    Real Options Signaling Games With Applications To Corporate Finance

    The authors study games in which the decision to exercise an option is a signal of private information to outsiders, whose beliefs affect the utility of the decision-maker. Signaling incentives distort the timing of exercise, and the direction of distortion depends on whether the decision-maker's utility increases or decreases in...

    Provided By Stanford University

  • White Papers // Sep 2010

    Choice Set Heterogeneity And The Role Of Advertising: An Analysis With Micro And Macro Data

    The authors show how to use micro-level survey data from a tracking study on brand awareness in conjunction with data on sales and advertising expenditures to improve the specification, estimation, and interpretation of aggregate discrete choice models of demand. In a departure from the commonly made full information assumption, they...

    Provided By Stanford University

  • White Papers // Nov 2010

    Marketing Models Of Consumer Demand

    Marketing researchers have used models of consumer demand to forecast future sales; to describe and test theories of consumer behavior; and to measure the response to marketing interventions. The basic framework typically starts from microfoundations of expected utility theory to obtain a statistical system that describes consumers' choices over available...

    Provided By Stanford University