Massachusetts Institute of Technology

Displaying 121-160 of 487 results

  • Webcasts // Feb 2011

    Excellence Is A Shared Path: Working Together For Justice And The Quality Of Life

    Exploring the past opens up new perspectives on the present and offers ways of navigating a challenging future, these speakers suggest, in a call to action on the occasion of Martin Luther King, Jr.'s birthday.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Feb 2011

    The Growth Of Cryptography

    It's not every day that Euclid appears in public with "Alice and Bob," but in a lecture spanning a few thousand years, the presenter summons these and other notables in his history of cryptography. While citing milestones of code-making and breaking, the presenter also brings his audience up to date...

    Provided By Massachusetts Institute of Technology

  • White Papers // Feb 2011

    The China Syndrome: Local Labor Market Effects Of Import Competition In The United States

    Growing import exposure spurs a substantial increase in transfer payments to individuals and households in the form of unemployment insurance benefits, disability benefits, income support payments, and in-kind medical benefits. These transfer payments are two orders of magnitude larger than the corresponding rise in Trade Adjustment Assistance benefits. Nevertheless, transfers...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Co-Designing Multi-Packet Reception, Network Coding, and MAC Using a Simple Predictive Model

    The authors design a cross-layer approach to optimize the joint use of multi-packet reception and network coding, in order to relieve congestion. The authors construct a model for the behavior of the 802.11 MAC and apply it to several key canonical topology components and their extensions to any number of...

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    The Future Of Finance

    In this webcast, the author chooses not to focus on the financial crisis. It is clear to him there were "Fools and knaves," as well as "Many structural elements that would have happened even if people were well behaved and well informed" - risks are simply "Embedded in our systems."

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    Finance In Action

    The moderator introduces the panelists as distinguished academics and practitioners who share not only their status as MIT alums, but also their innovative application of finance theory to entrepreneurship. "They were in the middle of the action," said the moderator.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    The Evolution Of Financial Technology

    An unmistakable glow of nostalgia rises from this reunion of "Five of the founding fathers of modern finance," in the words of the moderator. The speakers reminisce about their start in economics, and their professional lives at MIT, a decades-long era of intense collaboration and creativity that both transformed the...

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    Economic Policy Challenges: Microeconomics And Regulation

    Given its contributions to policy and practice in such key sectors as health care, industrial organization and technological innovation, and energy and the environment, microeconomics may not be getting the kind of respect, or at least attention, it deserves, the authors suggest.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    Economic Policy Challenges: Macroeconomics And Fiscal Policy

    The economists, MIT PhDs all, ponder what remains in the macroeconomist's toolkit to pull the U.S., and much of the developed world, out of recession. They discuss aspects of fiscal and monetary policy that may prove useful in spurring recovery, as well as the complicating matter of politics.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    The Evolution Of Economic Science: Macroeconomics, Growth, And Development

    This webcast first looks inward, at the evolution of macroeconomics in the past century, and the emergence of microeconomic foundations in macroeconomics, then shifts outward, to the application of economic analysis to such issues as structural unemployment, the ongoing U.S. recession, and the best ways to help developing nations.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    The Evolution Of Economic Science: Individual And Firm Behavior

    The astonishing contributions MIT has made to the world of economics emerged from "A melting pot of analytical tools and mathematical methods, mixed with a healthy interest in real world questions, grounded in real world problems," says the moderator, crystallizing many of the themes of the symposium, and its inaugural...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    CryptDB: A Practical Encrypted Relational DBMS

    CryptDB is a DBMS that provides provable and practical privacy in the face of a compromised database server or curious database administrators. CryptDB works by executing SQL queries over encrypted data. At its core are three novel ideas: an SQL-aware encryption strategy that maps SQL operations to encryption schemes, adjustable...

    Provided By Massachusetts Institute of Technology

  • Webcasts // Jan 2011

    Gaza In Crisis

    Two speakers steeped in the ongoing crisis of the Middle East describe abominable conditions for Palestinians living inside Gaza, which has been blockaded by Israel since 2007. They demand urgent action for civilian victims, and condemn both the Israeli and U.S. governments for pursuing policies of "Genocide."

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Scheduling for Small Delay in Multi-Rate Multi-Channel Wireless Networks

    This paper considers the problem of designing scheduling algorithms for multi-channel (e.g., OFDM-based) wireless downlink systems. The authors show that the Server-Side Greedy (SSG) rule introduced in earlier papers for ON-OFF channels performs well even for more general channel models. The key contribution in this paper is the development of...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Analysis and Algorithms for Partial Protection in Mesh Networks

    Mesh networks supporting data rates of multiple gigabytes per second are being deployed to meet the increasing demands of the telecom industry. As data rates continue to increase, the failure of a network line element or worse, a fiber cut, can result in severe service disruptions and large data loss,...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Scheduling in Parallel Queues With Randomly Varying Connectivity and Switchover Delay

    The authors consider a dynamic server control problem for two parallel queues with randomly varying connectivity and server switchover delay between the queues. At each time slot the server decides either to stay with the current queue or switch to the other queue based on the current connectivity and the...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Queue Length Asymptotics for Generalized Max-Weight Scheduling in the Presence of Heavy-Tailed Traffic

    Traditionally, traffic in telecommunication networks has been modeled using Poisson and Markov-modulated processes. These simple traffic models exhibit 'Local randomness', in the sense that much of the variability occurs in short time scales, and only an average behavior is perceived at longer time scales. With the spectacular growth of packet-switched...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    A Robust Optimization Approach to Backup Network Design With Random Failures

    This paper presents a scheme in which a dedicated backup network is designed to provide protection from random link failures. Upon a link failure in the primary network, traffic is rerouted through a preplanned path in the backup network. The authors introduce a novel approach for dealing with random link...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    A State Action Frequency Approach to Throughput Maximization Over Uncertain Wireless Channels

    The authors consider scheduling over a wireless system, where the channel state information is not available a priori to the scheduler, but can be inferred from the past. Specifically, the wireless system is modeled as a network of parallel queues. They assume that the channel state of each queue evolves...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Relational Cloud: A Database-as-a-Service for the Cloud

    This paper introduces a new transactional "DataBase-as-a-Service" (DBaaS) called Relational Cloud. A DBaaS promises to move much of the operational burden of provisioning, configuration, scaling, performance tuning, backup, privacy, and access control from the database users to the service operator, offering lower overall costs to users. Early DBaaS efforts include...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    No Bits Left Behind

    One of the key tenets of database system design is making efficient use of storage and memory resources. However, existing database system implementations are actually extremely wasteful of such resources; for example, most systems leave a great deal of empty space in tuples, index pages, and data pages, and spend...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Mobilized Ad-Hoc Networks: A Reinforcement Learning Approach

    With the cost of wireless networking and computational power rapidly dropping, mobile ad-hoc networks will soon become an important part of the society's computing structures. While there is a great deal of research from the networking community regarding the routing of information over such networks, most of these techniques lack...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Middleboxes No Longer Considered Harmful

    Intermediate network elements, such as Network Address Translators (NATs), firewalls, and transparent caches are now commonplace. The usual reaction in the network architecture community to these so-called middleboxes is a combination of scorn (because they violate important architectural principles) and dismay (because these violations make the Internet less flexible). While...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    How to Construct a Correct and Scalable IBGP Configuration

    The Internet's current interdomain routing protocol, BGP (Border Gateway Protocol), has two modes of operation: eBGP (external BGP), used to exchange routing information between autonomous systems, and iBGP (internal BGP), used to propagate that information within an Autonomous System (AS). In a "Full mesh" iBGP configuration, every router has a...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Energy-Efficient Dynamic Source Routing in Ad-Hoc Wireless Networks

    The authors present Span-DSR and DSR-PSM, two power-saving algorithms designed for ad-hoc wireless networks using source routing. Span-DSR reduces power consumption and has desirable fairness properties, while maintaining a connected backbone of nodes to route packets. Span-DSR's power saving protocol increases system lifetime by a factor of two better than...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Network-Wide BGP Route Prediction for Traffic Engineering

    The Internet consists of about 13,000 Autonomous Systems (AS's) that exchange routing information using the Border Gateway Protocol (BGP). The operators of each AS must have control over the flow of traffic through their network and between neighboring AS's. However, BGP is a complicated, policy-based protocol that does not include...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Performance of Multihop Wireless Networks: Shortest Path Is Not Enough

    Existing wireless ad hoc routing protocols typically find routes with the minimum hop-count. This paper presents experimental evidence from two wireless test-beds which shows that there are usually multiple minimum hop-count paths, many of which have poor throughput. As a result, minimum-hop-count routing often chooses routes that have significantly less...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Peering Peer-To-Peer Providers

    The early peer-to-peer applications eschewed commercial arrangements and instead established a grass-roots model in which the collection of end-users provided their own distributed computational infrastructure. While this cooperative end-user approach works well in many application settings, it does not provide a sufficiently stable platform for certain peer-to-peer applications (e.g., DHTs...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Geographic Routing Without Planarization

    The authors present a new geographic routing algorithm, the Greedy Distributed Spanning Tree Routing (GDSTR), that finds shorter routes and generates less maintenance traffic than previous algorithms. While geographic routing potentially scales well, it faces the problem of what to do at local dead ends where greedy forwarding fails. Existing...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Pastwatch: A Distributed Version Control System

    Pastwatch is a version control system that acts like a traditional client-server system when users are connected to the network; users can see each other's changes immediately after the changes are committed. When a user is not connected, Pastwatch also allows users to read revisions from the repository, commit new...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Proactive Replication for Data Durability

    Many wide area storage systems replicate data for durability. A common way of maintaining the replicas is to detect node failures and respond by creating additional copies of objects that were stored on failed nodes and hence suffered a loss of redundancy. Reactive techniques can minimize total bytes sent since...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    F2F: Reliable Storage in Open Networks

    A major hurdle to deploying a distributed storage infrastructure in peer-to-peer systems is storing data reliably using nodes that have little incentive to remain in the system. The authors argue that a node should choose its neighbors (The nodes with which it shares resources) based on existing social relationships instead...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    How to Construct a Correct and Scalable IBGP Conguration

    The Internet's current inter domain routing protocol, BGP (Border Gateway Protocol), has two modes of operation: eBGP (external BGP), used to exchange routing information between autonomous systems, and iBGP (internal BGP), used to propagate that information within an Autonomous System (AS). In a "Full mesh" iBGP configuration, every router has...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Peer-to-Peer Communication Across Network Address Translators

    Network Address Translation (NAT) causes well-known difficulties for Peer-To-Peer (P2P) communication, since the peers involved may not be reachable at any globally valid IP address. Several NAT traversal techniques are known, but their documentation is slim, and data about their robustness or relative merits is slimmer. This paper documents and...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Geographic Locality of IP Prefixes

    Information about the geographic locality of IP prefixes can be useful for understanding the issues related to IP address allocation, aggregation, and BGP routing table growth. In this paper, the authors use traceroute data and geographic mappings of IP addresses to study the geographic properties of IP prefixes and their...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Frequency Estimation of Internet Packet Streams With Limited Space

    The authors consider a router on the Internet analyzing the statistical properties of a TCP/IP packet stream. A fundamental difficulty with measuring traffic behavior on the Internet is that there is simply too much data to be recorded for later analysis, on the order of gigabytes a second. As a...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Targeting The Poor: Evidence From A Field Experiment In Indonesia

    This paper reports an experiment in 640 Indonesian villages that investigated three approaches to targeting the poor: Proxy-Means Tests (PMT), where a census of assets is used to predict consumption; community targeting, where villagers rank everyone from richest to poorest; and a hybrid. Defining poverty based on PPP$2 per-capita consumption,...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    The Portuguese High Speed Rail Network; Relating Financing To Strategic And Operating Issues

    This paper describes the implementation of the Portuguese High Speed Rail (HSR) Network. The business model developed by RAVE for the PPP's related with the HSR infrastructure is described and discussed. Following a recently awarded research project (EXPRESS) aimed at studying the strategic aspects related with the implementation of HSR...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Delay in Random Access Wireless Networks With Controlled Mobility

    This paper considers dynamic wireless networks where messages arriving randomly (in time and space) are collected by a mobile receiver. The messages are transmitted to the mobile receiver according to a random access scheme and the receiver dynamically adjusts its position in order to receive these messages in the least...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    An Empirical Study of "Bogo" Route Advertisements

    An important factor in the robustness of the inter-domain routing system is whether the routers in Autonomous Systems (ASes) filter routes for "Bogon" address space - i.e., private address space and address space that has not been allocated by the Internet Assigned Numbers Authority (IANA). This paper presents an empirical...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jun 2010

    Detecting Evolving Patterns of Self-Organizing Networks by Flow Hierarchy Measurement

    Hierarchies occur widely in evolving self-organizing ecological, biological, technological and social networks, but detecting and comparing hierarchies is difficult. Here the authors present a metric and technique to quantitatively assess the extent to which self-organizing directed networks exhibit a flow hierarchy. Flow hierarchy is a commonly observed but theoretically overlooked...

    Provided By Massachusetts Institute of Technology

  • White Papers // Apr 2010

    Arguments for an Information-Centric Internetworking Architecture

    The current Internet architecture focuses on communicating entities, largely leaving aside the information to be exchanged among them. However, trends in communication scenarios show that WHAT is being exchanged becoming more important than WHO are exchanging information. Van Jacobson describes this as moving from interconnecting machines to interconnecting information. Any...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    How to Construct a Correct and Scalable IBGP Configuration

    The Internet's current interdomain routing protocol, BGP (Border Gateway Protocol), has two modes of operation: eBGP (external BGP), used to exchange routing information between autonomous systems, and iBGP (internal BGP), used to propagate that information within an Autonomous System (AS). In a "Full mesh" iBGP configuration, every router has a...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jun 2009

    Wishbone: Profile-Based Partitioning for Sensornet Applications

    The ability to partition sensor network application code across sensor nodes and backend servers is important for running complex, data-intensive applications on sensor platforms that have CPU, energy, and bandwidth limitations. This paper presents Wishbone, a system that takes a dataflow graph of operators and produces an optimal partitioning. With...

    Provided By Massachusetts Institute of Technology

  • White Papers // Oct 2009

    Genetic Variation In Financial Decision Making

    Individuals differ in how they compose their investment portfolios, yet empirical models of portfolio risk typically only account for a small portion of the cross-sectional variance. This paper asks if genetic variation can explain some of these individual differences. Following a major pension reform Swedish adult had to compose a...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Energy-Efficient Dynamic Source Routing in Ad-Hoc Wireless Networks

    The authors present Span-DSR and DSR-PSM, two power-saving algorithms designed for ad-hoc wireless networks using source routing. Span-DSR reduces power consumption and has desirable fairness properties, while maintaining a connected backbone of nodes to route packets. Span-DSR's power saving protocol increases system lifetime by a factor of two better than...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Network-Wide BGP Route Prediction for Traffic Engineering

    The Internet consists of about 13,000 Autonomous Systems (AS's) that exchange routing information using the Border Gateway Protocol (BGP). The operators of each AS must have control over the flow of traffic through their network and between neighboring AS's. However, BGP is a complicated, policy-based protocol that does not include...

    Provided By Massachusetts Institute of Technology

  • White Papers // Aug 2009

    ESD And Health Care Systems: Some Strategic Considerations

    Proper health care delivery to a growing but aging population is becoming one of the most challenging tasks of the time. It becomes also one of the most complexes. Although many tools are at hand, grand designs and implementation systems are mostly lacking. In the industrialized countries, requests for optimal...

    Provided By Massachusetts Institute of Technology

  • White Papers // Aug 2009

    The 24-Hour Knowledge Factory Paradigm: The Evolving Model For Offshoring Based On Strategic, Economic, Legal, Health, Technical, And Other Considerations

    The 24-Hour Knowledge Factory paradigm involves 3 (or more) collaborating centers, each located in a different continent. Individuals at each center work from 9 am to 5 pm in that country, and then pass the work-in-progress to the next collaborating center to enable round-the clock performance in a manner somewhat...

    Provided By Massachusetts Institute of Technology

  • White Papers // Mar 2007

    Low-Cost Airports For Low-Cost Airlines: Flexible Design To Manage The Risks

    The paradigm of airport planning and design is changing fundamentally. Low-cost airlines have become significant drivers of airport planning, along with aircraft size and other technical factors. They have different requirements than the "Legacy" carriers. They focus on cost and on alternative ways to handle passengers. Now being sizeable participants...

    Provided By Massachusetts Institute of Technology

  • White Papers // May 2010

    Report: NSF Workshop on Future Wireless Communication Research

    The wireless communication industry is a trillion-dollar, worldwide business that represents a substantial fraction of the global Gross Domestic Product. Over the past two decades, it has had a transformative impact on the society and has revolutionized almost all aspects of human interaction. These networks are inescapably intertwined with the...

    Provided By Massachusetts Institute of Technology

  • White Papers // Apr 2009

    Minimum Energy Transmission Over a Wireless Channel With Deadline and Power Constraints

    The authors consider optimal rate-control for energy-efficient transmission of data, over a time-varying channel, with packet deadline constraints. Specifically, the problem scenario consists of a wireless transmitter with B units of data that must be transmitted by deadline T over a fading channel. The transmitter can control the transmission rate...

    Provided By Massachusetts Institute of Technology

  • White Papers // Mar 2010

    Throughput Optimization in Mobile Backbone Networks

    This paper describes new algorithms for throughput optimization in a mobile backbone network. This hierarchical communication framework combines mobile backbone nodes, which have superior mobility and communication capability, with regular nodes, which are constrained in mobility and communication capability. An important quantity of interest in mobile backbone networks is the...

    Provided By Massachusetts Institute of Technology

  • White Papers // Feb 2009

    Delay Analysis of Maximum Weight Scheduling in Wireless Ad Hoc Networks

    This Paper Studies Delay Properties of the Well known Maximum Weight Scheduling Algorithm in Wireless Ad Hoc Networks. The authors Consider Wireless Networks With Either One hop or Multi-Hop Flows. Specifically, This Paper Shows That the Maximum Weight Scheduling Algorithm Achieves Order Optimal Delay for Wireless Ad Hoc Networks With...

    Provided By Massachusetts Institute of Technology

  • White Papers // Aug 2009

    Understanding Broadband Speed Measurements

    Broadband speed has emerged as the single most commonly cited metric for characterizing the quality of broadband offerings. However speed measurements for the same service can vary significantly. These differences arise from a complex set of factors including different test methodologies and test conditions. For any testing methodology, teasing apart...

    Provided By Massachusetts Institute of Technology

  • White Papers // Sep 2009

    Broadband Microfoundations: The Need for Traffic Data

    To date, most of the empirical effort to understand broadband service markets has focused on availability and adoption metrics and data. Data of this sort is indeed valuable when the dominant policy questions concern penetration and uptake. However, as broadband availability and penetration saturate, such data will become less informative....

    Provided By Massachusetts Institute of Technology

  • White Papers // Aug 2009

    The Evolution of Internet Congestion

    This paper discusses the evolution of the congestion controls that govern all Internet traffic. In particular the authors chronicle and discuss the implications of the fact that the most significant "Congestion Signals" are increasingly coming from network operators, not the TCP stack. Providers now nudge users into different traffic patterns...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2009

    Measurement and Assessment of Broadband Availability

    This report is the second of two reports prepared for the John Adams Innovation Institute ("JAII") of the Massachusetts Technology Collaborative ("MTC")5 in order to assess and evaluate approaches for measuring the status of broadband Internet access ("BB") services in Massachusetts. The first report provided an assessment of the current...

    Provided By Massachusetts Institute of Technology

  • White Papers // Oct 2010

    SCADA for the Rest of Us: Unlicensed Bands Supporting Long-Range Communications

    The authors are on the cusp of the next big wave in Internet and wireless technology for the mass market: the emergence of ubiquitous smart environments capable of automated sensing and interaction with the physical world around one.. A critical ingredient for this future is the deployment and availability of...

    Provided By Massachusetts Institute of Technology

  • White Papers // Sep 2009

    Hybrid Wireless Broadband

    Wireless access networks are evolving rapidly and hold the promise of significantly altering the landscape for broadband competition. In a companion paper, the authors explained why wireless networks are unlikely to converge toward the sort of broadband platform network exemplified by wired Next Generation Access Networks. In this paper the...

    Provided By Massachusetts Institute of Technology

  • White Papers // Aug 2009

    On the Convergence of Wired and Wireless Access Network Architectures

    Wired and wireless access networks continue to evolve toward higher-capacity, multi-service systems. Recent wireless broadband networks such as 3G LTE and WiMax provide a general-purpose IP platform with over-the-top services at the application layer, which is similar to the design of wired IP platform networks. This paper examines whether wired...

    Provided By Massachusetts Institute of Technology

  • White Papers // Sep 2010

    Algebraic Network Coding Approach to Deterministic Wireless Relay Networks

    The deterministic wireless relay network model, introduced by Avestimehr et al., has been proposed for approximating Gaussian relay networks. This model, known as the ADT network model, takes into account the broadcast nature of wireless medium and interference. Avestimehr et al. showed that the Min-cut Max-flow theorem holds in the...

    Provided By Massachusetts Institute of Technology

  • White Papers // Sep 2010

    Accelerated Dual Descent for Network Optimization

    Dual descent methods are commonly used to solve network optimization problems because their implementation can be distributed through the network. However, their convergence rates are typically very slow. This paper introduces a family of dual descent algorithms that use approximate Newton directions to accelerate the convergence rate of conventional dual...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jun 2009

    Competition, Market Coverage, and Quality Choice in Interconnected Platforms

    The authors study duopoly competition between two interconnected Internet Service Providers (ISP) that compete in quality and prices for both Content Providers (CP) and consumers. They develop a game theoretic model using a two-sided market framework, where ISP's are modeled as interconnected plat-forms with quality bottlenecks; a consumer on a...

    Provided By Massachusetts Institute of Technology

  • White Papers // Dec 2009

    Near-Optimal Power Control in Wireless Networks: A Potential Game Approach

    The authors study power control in a multi-cell CDMA wireless system whereby self-interested users share a common spectrum and interfere with each other. The objective is to design a power control scheme that achieves a (near) optimal power allocation with respect to any predetermined network objective (such as the maximization...

    Provided By Massachusetts Institute of Technology

  • White Papers // Dec 2008

    Completion Time Minimization and Robust Power Control in Wireless Packet Networks

    A wireless packet network is considered in which each user transmits a stream of packets to its destination. The transmit power of each user interferes with the transmission of all other users. A convex cost function of the completion times of the user packets are minimized by optimally allocating the...

    Provided By Massachusetts Institute of Technology

  • White Papers // Nov 2008

    Competitive Scheduling in Wireless Collision Channels With Correlated Channel State

    The authors consider a wireless collision channel, shared by a finite number of mobile users who transmit to a common base station. Each user wishes to optimize its individual network utility that incorporates a natural tradeoff between throughput and power. The channel quality of every user is affected by global...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Performance of Multihop Wireless Networks: Shortest Path Is Not Enough

    Existing wireless ad hoc routing protocols typically find routes with the minimum hop-count. This paper presents experimental evidence from two wireless test-beds which shows that there are usually multiple minimum hop-count paths, many of which have poor throughput. As a result, minimum-hop-count routing often chooses routes that have significantly less...

    Provided By Massachusetts Institute of Technology

  • White Papers // Nov 2008

    Modeling Computational Security in Long-Lived Systems, Version 2

    For many cryptographic protocols, security relies on the assumption that adversarial entities have limited computational power. This type of security degrades progressively over the lifetime of a protocol. However, some cryptographic services, such as timestamping services or digital archives, are long-lived in nature; they are expected to be secure and...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Peering Peer-To-Peer Providers

    The early peer-to-peer applications eschewed commercial arrangements and instead established a grass-roots model in which the collection of end-users provided their own distributed computational infrastructure. While this cooperative end-user approach works well in many application settings, it does not provide a sufficiently stable platform for certain peer-to-peer applications (e.g., DHTs...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Geographic Routing Without Planarization

    The authors present a new geographic routing algorithm, the Greedy Distributed Spanning Tree Routing (GDSTR), that finds shorter routes and generates less maintenance traffic than previous algorithms. While geographic routing potentially scales well, it faces the problem of what to do at local dead ends where greedy forwarding fails. Existing...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Pastwatch: A Distributed Version Control System

    Pastwatch is a version control system that acts like a traditional client-server system when users are connected to the network; users can see each other's changes immediately after the changes are committed. When a user is not connected, Pastwatch also allows users to read revisions from the repository, commit new...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    Proactive Replication for Data Durability

    Many wide area storage systems replicate data for durability. A common way of maintaining the replicas is to detect node failures and respond by creating additional copies of objects that were stored on failed nodes and hence suffered a loss of redundancy. Reactive techniques can minimize total bytes sent since...

    Provided By Massachusetts Institute of Technology

  • White Papers // Jan 2011

    F2F: Reliable Storage in Open Networks

    A major hurdle to deploying a distributed storage infrastructure in peer-to-peer systems is storing data reliably using nodes that have little incentive to remain in the system. The authors argue that a node should choose its neighbors (The nodes with which it shares resources) based on existing social relationships instead...

    Provided By Massachusetts Institute of Technology

  • White Papers // Mar 2009

    Usher: Improving Data Quality With Dynamic Forms

    Data quality is a critical problem in modern databases. Data entry forms present the first and arguably best opportunity for detecting and mitigating errors, but there has been little research into automatic methods for improving data quality at entry time. In this paper, the authors propose Usher, an end-to-end system...

    Provided By Massachusetts Institute of Technology

  • Webcasts // Feb 2011

    The Fruits Of Diversity

    In a webcast the authors offers a bounty of visual and aural pleasures, a museum curator and two artists describe how their work "Dissolves boundaries," in the words of moderator, often "Leading to new frontiers."

    Provided By Massachusetts Institute of Technology

  • Webcasts // Feb 2011

    Excellence Is A Shared Path: Working Together For Justice And The Quality Of Life

    Exploring the past opens up new perspectives on the present and offers ways of navigating a challenging future, these speakers suggest, in a call to action on the occasion of Martin Luther King, Jr.'s birthday.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Mar 2009

    Values-Based Leadership

    A West Point start, army career, and a disciplined approach to distilling key life experiences have guided the author through his 20 years at Procter & Gamble. McDonald recommends a deliberate system of self-examination that results in an articulation of beliefs, which he sees as essential to strong leadership.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Mar 2009

    Distributed Leadership In The Obama Campaign

    The author, who cut his teeth on civil rights work and with Cesar Chavez's United Farm Workers, describes how the principles and practices he learned around organizing and leadership played out in the most recent presidential election.

    Provided By Massachusetts Institute of Technology

  • Webcasts // Feb 2009

    Politics And Popular Culture

    The 2008 presidential campaign may have fused politics and entertainment once and for all. Three panelists and moderator discuss the nature and implications of this convergence. One of the authors says that the conflation of politics and culture need not degrade politics, if people "Do it with integrity, with honor."

    Provided By Massachusetts Institute of Technology