University of Massachusetts

Displaying 1-40 of 159 results

  • White Papers // Feb 2013

    Yank: Enabling Green Data Centers to Pull the Plug

    Balancing a data center's reliability, cost, and carbon emissions is challenging. For instance, data centers designed for high availability require a continuous flow of power to keep servers powered on, and must limit their use of clean, but intermittent, renewable energy sources. In this paper, the authors present Yank, which...

    Provided By University of Massachusetts

  • White Papers // Dec 2012

    Compiling Relational Database Schemata Into Probabilistic Graphical Models

    A majority of scientific and commercial data is stored in relational databases. Probabilistic models over such datasets would allow probabilistic queries, error checking, and inference of missing values, but to this day machine learning expertise is required to construct accurate models. Fortunately, current probabilistic programming tools ease the task of...

    Provided By University of Massachusetts

  • White Papers // Oct 2012

    Everlasting Secrecy by Exploiting Non-Idealities of the Eavesdropper's Receiver

    Secure communication over a memoryless wiretap channel in the presence of a passive eavesdropper is considered. Traditional information-theoretic security methods require an advantage for the main channel over the eavesdropper channel to achieve a positive secrecy rate, which in general cannot be guaranteed in wireless systems. Here, the authors exploit...

    Provided By University of Massachusetts

  • White Papers // Aug 2012

    CloudCast: Cloud Computing for Short-term Mobile Weather Forecasts

    Since today's weather forecasts only cover large regions every few hours, their use in severe weather is limited. In this paper, the authors present CloudCast, an application that provides short-term weather forecasts depending on user's current location. Since severe weather is rare, CloudCast leverages pay-as-you-go cloud platforms to eliminate dedicated...

    Provided By University of Massachusetts

  • White Papers // Jun 2012

    Designing Privacy-Preserving Smart Meters with Low-Cost Microcontrollers

    Smart meters that track ne-grained electricity usage and implement sophisticated usage-based billing policies, e.g., based on time-of-use, are a key component of recent smart grid initiatives that aim to increase the electric grid's efficiency. A key impediment to widespread smart meter deployment is that ne-grained usage data indirectly reveals detailed...

    Provided By University of Massachusetts

  • White Papers // May 2012

    An Empirical Study of Memory Sharing in Virtual Machines

    Content-based page sharing is a technique often used in virtualized environments to reduce server memory requirements. Many systems have been proposed to capture the benefits of page sharing. However, there have been few analyses of page sharing in general, both considering its real-world utility and typical sources of sharing potential....

    Provided By University of Massachusetts

  • White Papers // Mar 2012

    ETransform: Transforming Enterprise Data Centers by Automated Consolidation

    Modern day enterprises have a large IT infrastructure comprising thousands of applications running on servers housed in tens of data centers geographically spread out. These enterprises periodically perform a transformation of their entire IT infrastructure to simplify, decrease operational costs and enable easier management. However, the large number of different...

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    SmartCap: Flattening Peak Electricity Demand in Smart Homes

    Flattening household electricity demand reduces generation costs, since costs are disproportionately affected by peak demands. While the vast majority of household electrical loads are interactive and have little scheduling flexibility (TVs, microwaves, etc.), a substantial fraction of home energy use derives from background loads with some, albeit limited, flexibility. Examples...

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    Physical Layer Security From Inter-Session Interference in Large Wireless Networks

    Physical layer secrecy in wireless networks in the presence of eavesdroppers of unknown location is considered. In contrast to prior schemes, which have expended energy in the form of cooperative jamming to enable secrecy, the authors develop schemes where multiple transmitters send their signals in a cooperative fashion to confuse...

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    Providing End-to-End Secure Communications in Wireless Sensor Networks

    In many Wireless Sensor Networks (WSNs), providing end to end secure communications between sensors and the sink is important for secure network management. While there have been many works devoted to hop by hop secure communications, the issue of end to end secure communications is largely ignored. In this paper,...

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    Energy-Aware Load Balancing in Content Delivery Networks

    Internet-scale distributed systems such as Content Delivery Networks (CDNs) operate hundreds of thousands of servers deployed in thousands of data center locations around the globe. Since, the energy costs of operating such a large IT infrastructure are a significant fraction of the total operating costs, the authors argue for redesigning...

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    An Effective Architecture and Algorithm for Detecting Worms With Various Scan Techniques

    Since the days of the Morris worm, the spread of malicious code has been the most imminent menace to the Internet. Worms use various scanning methods to spread rapidly. Worms that select scan destinations carefully can cause more damage than worms employing random scan. This paper analyzes various scan techniques....

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    Achievable Rates of Physical Layer Network Coding Schemes on the Exchange Channel

    Network coding, where relay nodes combine the information received from multiple flows rather than simply replicating and forwarding the received packets, has shown the promise of significantly improving system performance. In very recent work, researchers have presented methods for increasing system throughput by employing methods inspired by network coding to...

    Provided By University of Massachusetts

  • White Papers // Jan 2012

    Formal Analysis of Passive Measurement Inference Techniques

    Verifying the accuracy of a passive measurements-based inference technique under all possible network scenarios is a difficult challenge - the measurement point has limited observability of events along the path, and monitored paths can exhibit a wide range of network properties (packet loss, reordering, end-end delay, route changes). In this...

    Provided By University of Massachusetts

  • White Papers // Sep 2011

    Evaluation of the Universal Geocast Scheme for VANETs

    Recently, a number of communications schemes have been proposed for Vehicular Ad hoc NETworks (VANETs). A promising approach, the Universal Geocast Scheme (UGS), provides for a diverse variety of VANET-specific characteristics such as time-varying topology, protocol variation based on road congestion, and support for non line-of-sight communication. In this paper,...

    Provided By University of Massachusetts

  • White Papers // Sep 2011

    Analytical Design of Inter-Vehicular Communications for Collision Avoidance

    The authors address the analytical design of a communications system that seeks to provide timely safety information for drivers who are unaware of an imminent collision. They develop a model to characterize the delay requirements needed to prevent such collisions. By simultaneously addressing the multiuser interference and propagation effects such...

    Provided By University of Massachusetts

  • White Papers // Sep 2011

    Predico: A System for What-If Analysis in Complex Data Center Applications

    Modern data center applications are complex distributed systems with tens or hundreds of interacting software components. An important management task in data centers is to predict the impact of a certain workload or reconfiguration change on the performance of the application. Such predictions require the design of "What-if" models of...

    Provided By University of Massachusetts

  • White Papers // Jul 2011

    On Managing Quality of Experience of Multiple Video Streams in Wireless Networks

    Managing the Quality-of-Experience (QoE) of video streaming for wireless clients is becoming increasingly important due to the rapid growth of video traffic on wireless networks. The inherent variability of the wireless channel as well as the Variable Bit Rate (VBR) of the compressed video streams make managing the QoE a...

    Provided By University of Massachusetts

  • White Papers // Jun 2011

    Exploring the Feasibility of Low Cost Fault Injection Attacks on Sub-Threshold Devices Through an Example of a 65nm AES Implementation

    The continuous scaling of VLSI technology and the aggressive use of low power strategies (such as sub-threshold voltage) make it possible to implement standard cryptographic primitives within the very limited circuit and power budget of RFID devices. On the other hand, such cryptographic implementations raise concerns regarding their vulnerability to...

    Provided By University of Massachusetts

  • White Papers // Jun 2011

    Forensic Triage for Mobile Phones With DEC0DE

    The authors present DEC0DE, a system for recovering information from phones with unknown storage formats, a critical problem for forensic triage. Because phones have myriad custom hardware and software, they examine only the stored data. Via flexible descriptions of typical data structures, and using a classic dynamic programming algorithm, they...

    Provided By University of Massachusetts

  • White Papers // Jun 2011

    iMapReduce: A Distributed Computing Framework for Iterative Computation

    Relational data are pervasive in many applications such as data mining or social network analysis. These relational data are typically massive containing at least millions or hundreds of millions of relations. This poses demand for the design of distributed computing frameworks for processing these data on a large cluster. MapReduce...

    Provided By University of Massachusetts

  • White Papers // Jun 2011

    Financialization, Household Credit And Economic Slowdown In The U.S.

    Three important features of the U.S. economy during the neoliberal era since the mid-1970s have been: growing financialization, increasing household debt, and stagnant real wages for production and nonsupervisory workers. This paper develops a discrete-time Marxian circuit of capital model to analyze the links between these three features and economic...

    Provided By University of Massachusetts

  • White Papers // May 2011

    Entropy Extraction in Metastability-Based TRNG

    True Random Number Generators (TRNG) implemented in Deep Sub Micron (DSM) technologies become biased in bit generation due to process variations and fluctuations in operating conditions. A variety of mechanisms ranging from analog and digital circuit techniques to algorithmic post-processing can be employed to remove bias. In this paper, the...

    Provided By University of Massachusetts

  • White Papers // May 2011

    Empirical Analysis of the Evolution of Follower Network: A Case Study on Douban

    Follower networks such as Twitter and Digg are becoming popular form of social information networks. This paper seeks to gain insights into how they evolve and the relationship between their structure and their ability to spread information. By studying the Douban follower network, which is a popular online social network...

    Provided By University of Massachusetts

  • White Papers // May 2011

    BenchLab: An Open Testbed for Realistic Benchmarking of Web Applications

    Web applications have evolved from serving static content to dynamically generating Web pages. Web 2.0 applications include JavaScript and AJAX technologies that manage increasingly complex interactions between the client and the Web server. Traditional benchmarks rely on browser emulators that mimic the basic network functionality of real Web browsers but...

    Provided By University of Massachusetts

  • White Papers // Apr 2011

    A Hybrid Self-Calibration Technique to Mitigate the Effect of Variability in TRNG

    In this paper, the authors briefly study the effect of variability in process and operating conditions on the statistics and performance of on-chip True Random Number Generator (TRNG), using the cryptographic measure of bit entropy. Circuits designed in deep submicron technologies are susceptible to variation in process. The variability may...

    Provided By University of Massachusetts

  • White Papers // Apr 2011

    A New Virtual Indexing Method for Measuring Host Connection Degrees

    The authors present a new virtual indexing method for estimating host connection degrees for high-speed links. It is based on the virtual connection degree sketch where a compact sketch of network traffic is built by generating the associated virtual bitmaps for each host. Each virtual bitmap consists of a fixed...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    BenchLab: Benchmarking With Real Web Applications and Web Browsers

    Popular benchmarks such as TPC-W and RUBiS that are commonly used for evaluation by the systems community are no longer representative of modern Web applications. Many of these benchmarks lack the features such as JavaScript and AJAX that are essential to real Web 2.0 applications. Further, traditional benchmarks rely on...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    Finding a "Kneedle" in a Haystack: Detecting Knee Points in System Behavior

    Computer systems often reach a point at which the relative cost to increase some tunable parameter is no longer worth the corresponding performance benefit. These "Knees" typically represent beneficial points that system designers have long selected to best balance inherent trade-offs. While prior work largely uses ad hoc, system-specific approaches...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    E2R: Energy Efficient Routing for Multi-Hop Green Wireless Networks

    Wireless communication consumes a significant amount of energy in wireless networks. Most multi-hop wireless routing protocols are adopted from wired network routing protocols and use pre-selected single or multiple minimum cost paths to forward data packets. However, unlike wired networks, a wireless network has unique characteristics such as unreliable wireless...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    Dolly: Virtualization-Driven Database Provisioning for the Cloud

    Cloud computing platforms are becoming increasingly popular for e-commerce applications that can be scaled on-demand in a very cost effective way. Dynamic provisioning is used to autonomously add capacity in multi-tier cloud-based applications that see workload increases. While many solutions exist to provision tiers with little or no state in...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    TCP Over Optical Burst-Switched Networks With Controlled Burst Retransmission

    For Optical Burst-Switched (OBS) networks in which TCP is implemented at a higher layer, the loss of bursts can lead to serious degradation of TCP performance. Due to the bufferless nature of OBS, random burst losses may occur, even at low traffic loads. Consequently, these random burst losses may be...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    Improving TCP Performance Over Optical Burst-Switched (OBS) Networks Using Forward Segment Redundancy

    Random contentions occur in Optical Burst-Switched (OBS) networks because of one-way signaling and lack of optical buffers. These contentions can occur at low loads and are not necessarily an indication of congestion. The loss caused by them, however, causes TCP at the transport layer to reduce its send rate drastically,...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    Employer-Provided Health Insurance And Labor Supply Of Married Women

    This paper presents new evidence on the effect of husbands' health insurance on wives' labor supply. Previous cross-sectional studies have estimated a significant negative effect of spousal coverage on wives' labor supply. However, these estimates potentially suffer from bias due to the simultaneity of wives' labor supply and the health...

    Provided By University of Massachusetts

  • White Papers // Feb 2011

    Defending Against XML-Based Attacks Using State-Based XML Firewall

    With the proliferation of service-oriented systems and cloud computing, web services security has gained much attention in recent years. Web service attacks, called XML-based attacks, typically occur at the SOAP message level, thus they are not readily handled by existing security mechanisms such as a conventional firewall. In order to...

    Provided By University of Massachusetts

  • White Papers // Feb 2011

    Dynamic Anycast Routing and Wavelength Assignment in WDM Networks Using Ant Colony Optimization (ACO)

    Ant Colony Optimization (ACO) is a probabilistic technique used for solving complex computational problems, such as finding optimal routes in networks. It has been proved to perform better than simulated annealing and genetic algorithm approaches for solving dynamic problems. ACO algorithms can quickly adapt to real-time changes in the system....

    Provided By University of Massachusetts

  • White Papers // Feb 2011

    Employment Effects Under Planned Changes To The EPA's Air Pollution Rules

    The U.S. electric power sector is changing and modernizing in response to societal and market forces. Power companies face a business imperative to meet increasing pressures for cleaner, more efficient energy that will safeguard public health and protect the world's climate. These forces are already transforming the industry. Significant capital...

    Provided By University of Massachusetts

  • White Papers // Feb 2011

    Identifying Mobiles Hiding Behind Wireless Routers

    The Network Address Translation technique (NAT) is widely used in wireless routers. It is a low cost solution to IPv4 address space limitations. However, cyber criminals may abuse NAT and hide behind wireless routers to use mobile devices and conduct crimes. To identify a suspect mobile device, the authors should...

    Provided By University of Massachusetts

  • White Papers // Jan 2011

    Robust Multipath Routing in Large Wireless Networks

    One of the challenges of wireless networks is to provide a reliable end-to-end path between two end hosts in the face of link and node outages. These can occur due to fluctuations in channel quality, node movement, or node failure. One mechanism that has been proposed is based on multipath...

    Provided By University of Massachusetts

  • White Papers // Jan 2011

    Dynamic Cache Reconfiguration Strategies for a Cluster-Based Streaming Proxy

    The high bandwidth and the relatively longlived characteristics of digital video are key limiting factors in the wide-spread usage of streaming content over the Internet. The problem is further complicated by the fact that the video popularity changes over time. This paper studies caching issues for a cluster-based streaming proxy...

    Provided By University of Massachusetts

  • Presentations // Jan 2003

    What Is A Brand?

    A brand is the peculiar association that is developed among the target audience regarding a particular product or service. This association arises from the product or service attributes that differentiate that particular product or service from others. Brand equity is the competitive advantage established by the brand in the market...

    Provided By University of Massachusetts

  • White Papers // Jan 2009

    Capturing Data Uncertainty in High-Volume Stream Processing

    The authors present the design and development of a data stream system that captures data uncertainty from data collection to query processing to final result generation. Their system focuses on data that is naturally modeled as continuous random variables such as many types of sensor data. To provide an end-to-end...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    Employer-Provided Health Insurance And Labor Supply Of Married Women

    This paper presents new evidence on the effect of husbands' health insurance on wives' labor supply. Previous cross-sectional studies have estimated a significant negative effect of spousal coverage on wives' labor supply. However, these estimates potentially suffer from bias due to the simultaneity of wives' labor supply and the health...

    Provided By University of Massachusetts

  • White Papers // Aug 2010

    Multi-Target Tracking Using Proximity Sensors

    The authors consider the problem of tracking multiple moving targets in a continuous field using proximity sensors, which are binary sensors that can sense target presence by performing local energy detection subject to noise. Compared with more sophisticated sensors, proximity sensors have the advantage of having lower costs and lower...

    Provided By University of Massachusetts

  • White Papers // Jan 2011

    Secrecy in Wireless Networks Through Cooperative Chatter

    The secure transmission of information in wireless networks without knowledge of the eavesdroppers' locations is considered. Two key mechanisms are employed: artificial noise generation from system nodes other than the transmitter and receiver, and a form of multi-user diversity that allows message reception in the presence of the artificial noise....

    Provided By University of Massachusetts

  • White Papers // Aug 2010

    Target Tracking With Packet Delays and Losses - QoI Amid Latencies and Missing Data

    In this paper, the authors investigate how network and measurement components impact the quality of a tracking system. Specifically, they use Bayesian information to quantify the quality of target tracking and investigate how network quality and measurement quality affect the value of Bayesian information. By assuming a Brownian motion mobility...

    Provided By University of Massachusetts

  • White Papers // Aug 2009

    A Stochastic Geometry Approach to Transmission Capacity in Wireless Cooperative Networks

    The authors use a simple propagation model that only includes distance dependent path-loss and co-channel interferences, where the interference behavior is clearly presented by the stochastic geometry model. Consider, to evaluate the performance of more practical distributed ad hoc networks, the authors assume that all the transmitters are using ALOHA-type...

    Provided By University of Massachusetts

  • White Papers // Aug 2009

    Neighbor Discovery in Wireless Networks and the Coupon Collector's Problem

    Neighbor discovery is one of the first steps in the self-organization of a large wireless network. Neighbor discovery algorithms can be classified into two categories, viz. randomized or deterministic. In a randomized neighbor discovery algorithm, each node transmits at randomly chosen times and yet discovers all its neighbors by a...

    Provided By University of Massachusetts

  • White Papers // Sep 2009

    On the Application of Cooperative Transmission to Wireless Broadcast Channels

    In this paper, the authors study the application of cooperative diversity to wireless broadcast channels, a fundamental building block of wireless communication networks. Several cooperative broadcast protocols will be proposed, and information theoretic metrics are developed to facilitate performance evaluation. Provided that there is no direct S-D link, the proposed...

    Provided By University of Massachusetts

  • White Papers // Aug 2010

    Self-Tuning Routing Algorithms

    Self adapting protocols are attractive theoretically because they converge towards optimal operation, and practically because they eliminate classes of misconfiguration error. In order to achieve self adaption, a protocol needs to gather state information upon which to base decisions. This paper begins to address these issues by investigating the trade-off...

    Provided By University of Massachusetts

  • White Papers // Jan 2011

    Secrecy in Wireless Relay Channels Through Cooperative Jamming

    The ability to transmit a message securely in the presence of eavesdroppers in a dense wireless network is considered. As with a number of recent schemes, system nodes other than the transmitter and receiver are chosen to generate noise that confuses the eavesdropper. By exploiting the dynamics of the fading,...

    Provided By University of Massachusetts

  • White Papers // Aug 2010

    Security-Capacity Trade-Off in Large Wireless Networks Using Keyless Secrecy

    This paper presented the first work studying the scalability of keyless secrecy in a generalized network setting when the eavesdropper locations are unknown. The authors described a novel construction allowing nodes to generate artificial noise to overcome eavesdroppers. They then characterized the trade-offs between achievable node throughput and allowable number...

    Provided By University of Massachusetts

  • White Papers // Jul 2009

    Full Connectivity and Percolation in Large Cooperative Wireless Networks

    The authors study how physical layer cooperation impacts the requirements for asymptotic connectivity of large wireless networks. Under a model where receivers in a connected cluster cooperate, as well as the assumed cooperation between transmitters, they present a complete characterization of the conditions under which the network is fully connected...

    Provided By University of Massachusetts

  • White Papers // Jun 2011

    Financialization, Household Credit And Economic Slowdown In The U.S.

    Three important features of the U.S. economy during the neoliberal era since the mid-1970s have been: growing financialization, increasing household debt, and stagnant real wages for production and nonsupervisory workers. This paper develops a discrete-time Marxian circuit of capital model to analyze the links between these three features and economic...

    Provided By University of Massachusetts

  • White Papers // May 2010

    Understanding the Benefits of Opportunism and Cooperation in Multihop Wireless Networks

    Opportunism and cooperation have emerged as powerful techniques for increasing throughput in a wireless network by exploiting the broadcast nature of the medium. In this paper, the authors use simple Markov Chain models, augmented by simulation, to investigate the benefits of using opportunism and cooperation rather than traditional hop-by-hop, fixed-path...

    Provided By University of Massachusetts

  • White Papers // Feb 2011

    Defending Against XML-Based Attacks Using State-Based XML Firewall

    With the proliferation of service-oriented systems and cloud computing, web services security has gained much attention in recent years. Web service attacks, called XML-based attacks, typically occur at the SOAP message level, thus they are not readily handled by existing security mechanisms such as a conventional firewall. In order to...

    Provided By University of Massachusetts

  • White Papers // Sep 2010

    The Wage Penalty For State And Local Government Employees In New England

    Recent reports in the national and the regional media have described state and local government employees as earning more than workers in the private sector. The average state and local government worker does earn higher wages - but this is because they are, on average, older and substantially better educated...

    Provided By University of Massachusetts

  • White Papers // Jun 2009

    CCCP: Secure Remote Storage for Computational RFIDs

    Passive RFID tags harvest their operating energy from an interrogating reader, but constant energy shortfalls severely limit their computational and storage capabilities. The paper proposes Cryptographic Computational Continuation Passing (CCCP), a mechanism that amplifies programmable passive RFID tags' capabilities by exploiting an often overlooked, plentiful resource: low-power radio communication. While...

    Provided By University of Massachusetts

  • White Papers // Sep 2009

    Decision Support System for Resource Allocation in Disaster Management

    Natural and man-made disasters, such as earthquakes, floods, plane crashes, high-rise building collapses, major nuclear facility malfunctions, pose an ever-present challenge to public emergency services. Disasters may result in a large volume of responders arriving on-scene to provide assistance to victims. Coordination of responding resources is a major problem in...

    Provided By University of Massachusetts

  • White Papers // Oct 2009

    Supply Chain Network Design Under Profit Maximization and Oligopolistic Competition

    This paper models the supply chain network design problem with oligopolistic firms who are involved in the competitive production, storage, and distribution of a homogeneous product to multiple demand markets. The profit-maximizing firms select both the capacities associated with the various supply chain network activities as well as the product...

    Provided By University of Massachusetts

  • White Papers // Mar 2010

    On the Coverage and Detectability of Large-Scale Wireless Sensor Networks

    Advances in sensor and communication technologies have made it possible to manufacture small sensors with sensing, processing, and wireless communication capabilities in a cost-effective fashion. A sensor network can be formed by deploying specialized sensors in the region of interest to perform certain sensing and networking tasks. Application scenarios of...

    Provided By University of Massachusetts

  • White Papers // Jan 2011

    On the Benefits of Random Linear Coding for Unicast Applications in Disruption Tolerant Networks

    In this paper, the authors investigate the benefits of using a form of network coding known as Random Linear Coding (RLC) for unicast communications in a mobile Disruption Tolerant Network (DTN) under epidemic routing. Under RLC, DTN nodes store and then forward random linear combinations of packets as they encounter...

    Provided By University of Massachusetts

  • White Papers // Jan 2011

    Robust Multipath Routing in Large Wireless Networks

    One of the challenges of wireless networks is to provide a reliable end-to-end path between two end hosts in the face of link and node outages. These can occur due to fluctuations in channel quality, node movement, or node failure. One mechanism that has been proposed is based on multipath...

    Provided By University of Massachusetts

  • White Papers // Apr 2011

    A New Virtual Indexing Method for Measuring Host Connection Degrees

    The authors present a new virtual indexing method for estimating host connection degrees for high-speed links. It is based on the virtual connection degree sketch where a compact sketch of network traffic is built by generating the associated virtual bitmaps for each host. Each virtual bitmap consists of a fixed...

    Provided By University of Massachusetts

  • White Papers // Mar 2011

    E2R: Energy Efficient Routing for Multi-Hop Green Wireless Networks

    Wireless communication consumes a significant amount of energy in wireless networks. Most multi-hop wireless routing protocols are adopted from wired network routing protocols and use pre-selected single or multiple minimum cost paths to forward data packets. However, unlike wired networks, a wireless network has unique characteristics such as unreliable wireless...

    Provided By University of Massachusetts

  • White Papers // Sep 2010

    Network Coding Aware Rate Selection in Multi-Rate IEEE 802.11

    Network coding has been proposed as an alternative to the conventional store-and-forward routing paradigm for data delivery in networks. When deployed in a multi-rate wireless network, network coding has to interact with rate adaptation. When multicasting packets (a requirement of network coding) in a multi-rate IEEE 802.11 wireless network, one...

    Provided By University of Massachusetts

  • White Papers // May 2010

    Redundancy-Aware Routing With Limited Resources

    Network load is reduced upon elimination of redundant data transfer. Redundancy Elimination (RE) techniques can be applied on a per-packet basis, and provide benefit regardless of application. While it is straightforward to apply RE on a per-link basis, network cost can be further reduced by applying RE network-wide: by routing...

    Provided By University of Massachusetts

  • White Papers // Dec 2009

    Modeling Redundancy-Based Routing in Delay Tolerant Networks

    Delay Tolerant Networks (DTNs) are usually intermittently connected mobile wireless networks. Routing in delay tolerant networks is challenging because many well-known assumptions of traditional networks do not hold in DTNs. Various routing schemes have been proposed in literature which exploit redundancy to improve the message delivery. However, there lacks a...

    Provided By University of Massachusetts

  • White Papers // Apr 2010

    Sustainable Supply Chain Network Design: A Multicriteria Perspective

    This paper develops a rigorous modeling and analytical framework for the design of sustainable supply chain networks. The paper considers a firm that is engaged in determining the capacities of its various supply chain activities, that is, the manufacturing, storage, and distribution of the product to the demand locations. The...

    Provided By University of Massachusetts

  • White Papers // May 2010

    Disaster Recovery as a Cloud Service: Economic Benefits & Deployment Challenges

    Many businesses rely on Disaster Recovery (DR) services to prevent either manmade or natural disasters from causing expensive service disruptions. Unfortunately, current DR services come either at very high cost, or with only weak guarantees about the amount of data lost or time required to restart operation after a failure....

    Provided By University of Massachusetts

  • White Papers // Jun 2010

    Results on Finite Wireless Networks on a Line

    Today, due to the vast amount of literature on large-scale wireless networks, the people have a fair understanding of the asymptotic behavior of such networks. However, in real world the people have to face finite networks for which the asymptotic results cease to be valid. The authors refer to networks...

    Provided By University of Massachusetts

  • White Papers // Sep 2011

    Evaluation of the Universal Geocast Scheme for VANETs

    Recently, a number of communications schemes have been proposed for Vehicular Ad hoc NETworks (VANETs). A promising approach, the Universal Geocast Scheme (UGS), provides for a diverse variety of VANET-specific characteristics such as time-varying topology, protocol variation based on road congestion, and support for non line-of-sight communication. In this paper,...

    Provided By University of Massachusetts

  • White Papers // Sep 2011

    Analytical Design of Inter-Vehicular Communications for Collision Avoidance

    The authors address the analytical design of a communications system that seeks to provide timely safety information for drivers who are unaware of an imminent collision. They develop a model to characterize the delay requirements needed to prevent such collisions. By simultaneously addressing the multiuser interference and propagation effects such...

    Provided By University of Massachusetts

  • White Papers // Jan 2010

    A Universal Geocast Scheme for Vehicular Ad Hoc Networks

    A universal communications scheme for Vehicular Ad hoc NETworks (VANETs) is proposed. This scheme accounts for a diverse variety of VANET-specific characteristics such as the gradual introduction of technology, highly dynamic topology, road-constrained vehicle movement and the presence of obstacles. The scheme incorporates a geometrical framework previously proposed by the...

    Provided By University of Massachusetts

  • White Papers // Aug 2009

    A Geometrical Analysis of Obstructed Wireless Networks

    Obstructions between communicating pairs reduce the reliability of data transfer in high frequency wireless networks, for which Vehicular Ad Hoc Networks serve as an emerging example. In this paper, the authors introduce a geometric framework which enables one to analyze the effect of obstacles on the capacity of such networks....

    Provided By University of Massachusetts

  • White Papers // Aug 2009

    Geometry-Aware Probabilistic Communications for Urban Vehicular Ad Hoc Networks

    Safety message exchange embodies a crucial proportion of inter-vehicle communications in Vehicular Ad Hoc Networks. In prior studies, direct single-hop broadcast seems a promising approach for simple transportation networks such as highways. In urban areas the geometry of roads and the placement of obstacles plays an important role in determining...

    Provided By University of Massachusetts

  • White Papers // Jul 2009

    The Effect of VII Market Penetration on Safety and Efficiency of Transportation Networks

    The introduction of the Vehicle Infrastructure Integration (VII) initiative by the US Department Of Transportation (USDOT) has recently attracted the attention of researchers and given rise to a plethora of studies, each one seeking to enhance the safety and efficiency of transportation networks in one way or another. Moreover, vehicles...

    Provided By University of Massachusetts

  • White Papers // Jan 2010

    Scaling Laws for Distance Limited Communications in Vehicular Ad Hoc Networks

    In this paper, the authors propose a framework to study the asymptotical capacity of Vehicular Ad Hoc NETworks (VANET)s when nodes are expected to communicate only when they reside in a certain distance of each other. This is quite a favorable scenario for VANETs when they are utilized for accident...

    Provided By University of Massachusetts

  • White Papers // Feb 2011

    Identifying Mobiles Hiding Behind Wireless Routers

    The Network Address Translation technique (NAT) is widely used in wireless routers. It is a low cost solution to IPv4 address space limitations. However, cyber criminals may abuse NAT and hide behind wireless routers to use mobile devices and conduct crimes. To identify a suspect mobile device, the authors should...

    Provided By University of Massachusetts

  • White Papers // Jul 2010

    Finding and Mending Barrier Gaps in Wireless Sensor Networks

    Constructing sensing barriers using wireless sensor networks has important applications in military operations and homeland security. The goal of forming a sensing barrier is to detect intruders attempting to cross the network. Early studies often assume that sensors remain static once deployed. The authors note that barrier gaps may occur...

    Provided By University of Massachusetts