Purdue University

Displaying 1-40 of 236 results

  • White Papers // Jul 2012

    Fast Rendezvous for Multiple Clients for Cognitive Radios Using Coordinated Channel Hopping

    A primary challenge in exploiting Cognitive Radio Networks (CRNs), known as the rendezvous problem, is for the users to find each other in the dynamic open spectrum. The authors study blind rendezvous, where users search for each other without any infrastructural aid. Previous work in this area have focused on...

    Provided By Purdue University

  • White Papers // Jun 2012

    Multi-Armed Bandit Congestion Control in Multi-Hop Infrastructure Wireless Mesh Networks

    Congestion control in multi-hop infrastructure wireless mesh networks is both an important and a unique problem. It is unique because it has two prominent causes of failed transmissions which are difficult to tease apart-lossy nature of wireless medium and high extent of congestion around gateways in the network. The concurrent...

    Provided By Purdue University

  • White Papers // Jun 2012

    PRIVATUS: Wallet-Friendly Privacy Protection for Smart Meters

    In smart power grids, a smart meter placed at a consumer-end point reports fine-grained usage information to utility providers. Based on this information, the providers can perform demand prediction and set on-demand pricing. However, this also threatens user privacy, since users' specific activity or behavior patterns can be deduced from...

    Provided By Purdue University

  • White Papers // Apr 2012

    An Energy-Efficient Approach for Provenance Transmission in Wireless Sensor Networks

    Assessing the trustworthiness of sensor data and transmitters of this data is critical for quality assurance. Trust evaluation frameworks utilize data provenance along with the sensed data values to compute the trustworthiness of each data item. However, in a sizeable multi-hop sensor network, provenance information requires a large and variable...

    Provided By Purdue University

  • White Papers // Apr 2012

    An Empirical Study of the Robustness of Inter-Component Communication in Android

    Over the last three years, Android has established itself as the largest-selling operating system for smartphones. It boasts of a Linux-based robust kernel, a modular framework with multiple components in each application, and a security-conscious design where each application is isolated in its own virtual machine. However, all of these...

    Provided By Purdue University

  • White Papers // Mar 2012

    A Study of Soft Error Consequences in Hard Disk Drives

    Hard disk drives have multiple layers of fault tolerance mechanisms that protect against data loss. However, a few failures occasionally breach the entire set of mechanisms. To prevent such scenarios, the authors rely on failure prediction mechanisms to raise alarms with sufficient warning to allow the at-risk data to be...

    Provided By Purdue University

  • White Papers // Jan 2012

    Towards a Differentially Private Data Anonymization

    Maximizing data usage and minimizing privacy risk are two conflicting goals. Organizations always hide the owners' identities and then apply a set of transformations on their data before releasing it. While determining the best set of transformations has been the focus of extensive work in the database community, most of...

    Provided By Purdue University

  • White Papers // Jan 2012

    Specification and Verification of a Context-Based Access Control Framework for Cyber Physical Systems

    Cyber Physical Systems (CPS) are complex systems that operate in a dynamic environment where security characteristics of contexts are unique, and uniform access to secure resources anywhere anytime to mobile entities poses daunting challenges. To capture context parameters such as location and time in an access control policy for CPS,...

    Provided By Purdue University

  • White Papers // Jan 2012

    Content Retrieval Using Cloud-Based DNS

    Cloud-computing systems are rapidly gaining momentum, providing flexible alternatives to many services. The authors study the Domain Name System (DNS) service, used to convert host names to IP addresses, which has historically been provided by a client's Internet Service Provider (ISP). With the advent of cloud-based DNS providers such as...

    Provided By Purdue University

  • White Papers // Jan 2012

    Realizing the Full Potential of PSM Using Proxying

    The Wi-Fi radio in Smartphones consumes a significant portion of energy when active. To reduce the energy consumption, the Power Saving Mode was standardized in IEEE 802.11 and two major implementations, Static PSM and Dynamic PSM, have been widely used in mobile devices. Unfortunately, both PSMs have inherent drawbacks: Static...

    Provided By Purdue University

  • White Papers // Jan 2012

    Downscaling Network Scenarios With Denial of Service (DoS) Attacks

    A major challenge that researchers face in studying Denial of Service (DoS) attacks is the size of the network to be investigated. A typical DoS attack usually takes place over a large portion of the Internet and involves a considerable number of hosts. This can be intractable for test-bed experimentation,...

    Provided By Purdue University

  • White Papers // Jan 2012

    Zephyr: Efficient Incremental Reprogramming of Sensor Nodes Using Function Call Indirections and Difference Computation

    Wireless reprogramming of sensor nodes is an essential requirement for long-lived networks since the software functionality changes over time. The amount of information that needs to be wirelessly transmitted during reprogramming should be minimized since reprogramming time and energy depend chiefly on the amount of radio transmissions. In this paper,...

    Provided By Purdue University

  • White Papers // Jan 2012

    On the Cost of Network Inference Mechanisms

    An important class of network inference mechanisms estimate the properties (e.g., delay or loss) of a large number of end-to-end network paths by measuring some subset thereof. This class of mechanisms is designed to reduce the amount of injected active measurement probe traffic and effort required to collect a large...

    Provided By Purdue University

  • White Papers // Jan 2012

    Constructing Maximum-Lifetime Data Gathering Forests in Sensor Networks

    Energy efficiency is critical for wireless sensor networks. The data gathering process must be carefully designed to conserve energy and extend network lifetime. For applications where each sensor continuously monitors the environment and periodically reports to a base station, a tree-based topology is often used to collect data from sensor...

    Provided By Purdue University

  • White Papers // Jan 2012

    Synergy: An Overlay Internetworking Architecture and Implementation

    A multitude of overlay network designs for resilient routing, multicasting, quality of service, content distribution, storage, and object location have been proposed. Overlay networks offer several attractive features, including ease of deployment, flexibility, adaptivity, and an infrastructure for collaboration among hosts. In this paper, the authors explore cooperation among coexisting,...

    Provided By Purdue University

  • White Papers // Jan 2012

    On the Impact of Filters on Analyzing Prefix Reachability in the Internet

    The reachability of IP address prefixes exhibits significant fluctuations due to changes in both physical connectivity and ISP routing policies. In the late 1990s, Labovitz et al. performed an extensive study of inter-domain path stability by analyzing BGP routing data. To reduce the noise in the BGP data, e.g., transient...

    Provided By Purdue University

  • White Papers // Dec 2011

    Immunizing Mobile Ad Hoc Networks Against Collaborative Attacks Using Cooperative Immune Model

    In this paper, a security problem of cooperative immunization against collaborative attacks such as blackhole attacks and wormhole attacks, in the mobile ad hoc networks such as the Worldwide Interoperability for Microwave Access (WiMAX) networks, was discussed. Due to the vulnerabilities of the protocol suites, collaborative attacks in the mobile...

    Provided By Purdue University

  • White Papers // Dec 2011

    Automatic Fault Characterization Via Abnormality-Enhanced Classification

    Enterprise and high-performance computing systems are growing extremely large and complex, employing many processors and diverse software/hardware stacks. As these machines grow in scale, faults become more frequent and system complexity makes it difficult to detect and diagnose them. The difficulty is particularly large for faults that degrade system performance...

    Provided By Purdue University

  • White Papers // Nov 2011

    DIMSUM: Discovering Semantic Data of Interest From Un-Mappable Memory With Confidence

    Uncovering semantic data of interest in memory pages without memory mapping information is an important capability in computer forensics. Existing memory mapping-guided techniques do not work in that scenario as pointers in the un-mappable memory cannot be resolved and navigated. To address this problem, the authors present a probabilistic inference-based...

    Provided By Purdue University

  • White Papers // Oct 2011

    A Framework for Composition and Enforcement of Privacy-Aware and Context-Driven Authorization Mechanism for Complex Systems

    Security and privacy of complex systems is a concern due to proliferation of cyber based technologies. Several researchers have pointed out that for the proper enforcement of privacy rules in a complex system, the privacy requirements should be captured in access control systems. In this paper, the authors present a...

    Provided By Purdue University

  • White Papers // Sep 2011

    Replicating Real-Time Garbage Collector

    Real-time Java is becoming a viable platform for real-time applications, bringing new challenges to a garbage collector. A real-time collector has to be incremental as not to cause deadline misses by suspending an application for too long. In particular, if a real-time collector has to relocate objects in the heap,...

    Provided By Purdue University

  • White Papers // Sep 2011

    3-Clique Attacks in Online Social Networks

    Online Social Networks (OSNs) have become ubiquitous in the past few years, counting hundreds of millions of people as members. In this paper, the authors show that the ease of accessing third party information by engineering OSN features, makes users vulnerable to infiltration attacks. Providing invaluable user context information, such...

    Provided By Purdue University

  • White Papers // Aug 2011

    Private Searching for Single and Conjunctive Keywords on Streaming Data

    Private searching on streaming data allows a user to collect potentially useful information from huge streaming sources of data without revealing his or her searching criteria. This technique can be used for airports, without knowing a classified "Possible terrorists" list, to find if any of hundreds of passenger lists has...

    Provided By Purdue University

  • White Papers // Aug 2011

    A Design for Securing Data Delivery in Mesh-Based Peer-to-Peer Streaming

    While mesh-based approaches have emerged as the dominant architecture for P2P streaming, the performance of these approaches under malicious participants has received little attention. In this paper, the authors provide taxonomy of the implicit commitments made by nodes when peering with others. They show that when these commitments are not...

    Provided By Purdue University

  • White Papers // Jul 2011

    Secure Configuration of Intrusion Detection Sensors for Changing Enterprise Systems

    Current attacks to distributed systems involve multiple steps, due to attackers usually taking multiple actions to achieve their goals. Such attacks are called multi-stage attacks and have the ultimate goal to compromise a critical asset for the victim. An example would be com-promising a web server, then achieve a series...

    Provided By Purdue University

  • White Papers // Jul 2011

    V-CAPS: A Con Dentiality and Anonymity Preserving Routing Protocol for Content-Based Publish-Subscribe Networks

    Content-Based Publish-Subscribe (CBPS) is a widely used communication paradigm where publishers "Publish" messages and a set of subscribers receive these messages based on their interests through filtering and routing by an intermediate set of brokers. CBPS has proven to be suitable for many-to-many communication offering flexibility and efficiency in communications...

    Provided By Purdue University

  • White Papers // Jul 2011

    Dangers and Joys of Stock Trading on The Web: Failure Characterization of a Three-Tier Web Service

    Characterizing latent software faults is crucial to address dependability issues of current three-tier systems. A client should not have a misconception that a transaction succeeded, when in reality, it failed due to a silent error. The authors present a fault injection-based evaluation to characterize silent and non-silent software failures in...

    Provided By Purdue University

  • White Papers // Jul 2011

    Real-time Mobile-Cloud Computing for Context-Aware Blind Navigation

    Context-awareness is a critical aspect of safe navigation, especially for the blind and visually impaired in unfamiliar environments. Existing mobile devices for context-aware navigation fall short in many cases due to their dependence on specific infrastructure requirements as well as having limited access to resources that could provide a wealth...

    Provided By Purdue University

  • White Papers // May 2011

    Collecting Transactional Garbage

    Transactional memory holds some promise to improve the practice of concurrent programming, but achieving acceptable performance remains an issue for large-scale adoption of the technology. Implementations of software transactional memory increase the cost of many frequently executed operations and have subtle interactions with the run-time system of the host language....

    Provided By Purdue University

  • White Papers // May 2011

    Enabling Flow-Level Latency Measurements Across Routers in Data Centers

    Detecting and localizing latency-related problems at router and switch levels is an important task to network operators as latency-critical applications in a data center network become popular. This however requires that measurement instances must be deployed at each and every router/switch in the network. In this paper, the authors study...

    Provided By Purdue University

  • White Papers // May 2011

    TxComm: Transforming Stream Communication for Load Balance, Efficiency, and Fault-Tolerance in Networks-on-Chip

    Recent work has examined using application-specific knowledge of streaming communication to optimize network routing (for throughput/performance) and/or design (for simpler hardware). However, previous techniques have assumed that the communication streams are directly mapped to networks-on-chip. In contrast, this paper explores the use of communication transformations (TxComm) to achieve higher throughput...

    Provided By Purdue University

  • White Papers // May 2011

    Attribute Based Group Key Management

    Attribute based systems enable fine-grained access control among a group of users each identified by a set of attributes. Secure collaborative applications need such flexible attribute based systems for managing and distributing group keys. However, current group key management schemes are not well designed to manage group keys based on...

    Provided By Purdue University

  • White Papers // May 2011

    Energy-Efficient Provenance Transmission in Large-Scale Wireless Sensor Networks

    Large-scale sensor-based decision support systems are being widely deployed. Assessing the trustworthiness of sensor data and the owners of this data is critical for quality assurance of decision making in these systems. Trust evaluation frameworks use data provenance along with the sensed data values to compute the trustworthiness of each...

    Provided By Purdue University

  • White Papers // May 2011

    Opportunistic Flooding to Improve TCP Transmit Performance in Virtualized Clouds

    Virtualization is a key technology that powers cloud computing platforms such as Amazon EC2. Virtual Machine (VM) consolidation, where multiple VMs share a physical host, has seen rapid adoption in practice with increasingly large number of VMs per machine and per CPU core. The authors' investigations, however, suggest that the...

    Provided By Purdue University

  • White Papers // May 2011

    Leave Them Microseconds Alone: Scalable Architecture for Maintaining Packet Latency Measurements

    Latency has become an important metric for network monitoring since the emergence of new latency-sensitive applications (e.g., algorithmic trading and high-performance computing). To satisfy the need, researchers have proposed new architectures such as LDA and RLI that can provide fine-grained latency measurements. However, these architectures are fundamentally ossified in their...

    Provided By Purdue University

  • White Papers // Apr 2011

    Efficient Online WiFi Delivery of Layered-Coding Media Using Inter-Layer Network Coding

    A primary challenge in multicasting video in a wireless LAN to multiple clients is to deal with the client diversity - clients may have different channel characteristics and hence receive different numbers of transmissions from the AP. A promising approach to overcome this problem is to combine multi-resolution (layered) video...

    Provided By Purdue University

  • White Papers // Apr 2011

    Biometrics-Based Authentication: A New Approach

    Authentication is a fundamental issue to any trust oriented computing system and also a critical part in many security protocols. Performing authentication is notoriously difficult. Biometrics has been widely used and adopted as a promising authentication method due to its advantages over some existing methods, particularly, its resistance to losses...

    Provided By Purdue University

  • White Papers // Apr 2011

    Dealer: Dynamic Request Splitting for Performance-Sensitive Applications in Multi-Cloud Environments

    Enterprises are increasingly deploying their applications in the cloud given the cost-saving advantages, and the potential to geo-distribute applications to ensure resilience and better service experience. However, a key unknown is whether it is feasible to meet the stringent response time requirements of enterprise applications using the cloud. The authors...

    Provided By Purdue University

  • White Papers // Apr 2011

    The Eval That Men Do: A Large-Scale Study of the Use of Eval in JavaScript Applications

    Transforming text into executable code with a function such as Java-Script's eval endows programmers with the ability to extend applications, at any time, and in almost any way they choose. But, this expressive power comes at a price: reasoning about the dynamic behavior of programs that use this feature becomes...

    Provided By Purdue University

  • White Papers // Apr 2011

    ?SETL: A Set Based Programming Abstraction for Wireless Sensor Networks

    Cyber-Physical Systems (CPSs) are poised to play a pivotal role in engineering new solutions to a variety of societal-scale problems, such as energy conservation, climate change, healthcare, transportation, etc. Networked embedded systems, such as Wireless Sensor Networks (WSNs), form a crucial building block for realizing large-scale CPSs and have received...

    Provided By Purdue University

  • White Papers // Dec 2009

    Throughput and Delay Analysis on Uncoded and Coded Wireless Broadcast With Hard Deadline Constraints

    Multimedia streaming applications have stringent QoS requirements. Typically each packet is associated with a packet delivery deadline. This work models and considers realtime streaming broadcast for stored-video over the downlink of a single cell. The broadcast capacity of the system subject to deadline constraints are derived for both uncoded and...

    Provided By Purdue University

  • White Papers // Sep 2010

    The Streaming Capacity of Sparsely-Connected P2P Systems With Distributed Control

    Peer-To-Peer (P2P) streaming technologies can take advantage of the upload capacity of clients, and hence can scale to large content distribution networks with lower cost. A fundamental question for P2P streaming systems is the maximum streaming rate that all users can sustain. Prior works have studied the optimal streaming rate...

    Provided By Purdue University

  • White Papers // Jan 2011

    An Optimization Based Approach for Quality of Service Routing in High-Bandwidth Networks

    In this paper, the authors propose an optimization based approach for Quality of Service routing in high-bandwidth networks. They view a network that employs QoS routing as an entity that distributively optimizes some global utility function. By solving the optimization problem, the network is driven to an efficient operating point....

    Provided By Purdue University

  • White Papers // Sep 2009

    On the Queue-Overflow Probability of Wireless Systems : A New Approach Combining Large Deviations With Lyapunov Functions

    In this paper the authors study the problem of characterizing the queue-overflow probability of wireless scheduling algorithms. In wireless networks operated under queue-length-based wireless scheduling algorithms, there often exists a tight coupling between the service-rate process, the system backlog process, the arrival process and the channel variations. Although one can...

    Provided By Purdue University

  • White Papers // Jan 2011

    Simplification of Network Dynamics in Large Systems

    In this paper the authors show that significant simplicity can be exploited for pricing-based control of large networks. They first consider a general loss network with Poisson arrivals and arbitrary holding time distributions. In dynamic pricing schemes, the network provider can charge different prices to the user according to the...

    Provided By Purdue University

  • White Papers // Feb 2011

    OFDM Downlink Scheduling for Delay-Optimality: Many-Channel Many-Source Asymptotics With General Arrival Processes

    The authors consider the downlink of an OFDM system for supporting a large number of delay-sensitive users. The OFDM scheduling problem can be modeled as a discrete-time multisource multi-server queuing system with time-varying connectivity. For such a system, the Max-Weight policy is known to be throughput-optimal and the Server-Side Greedy...

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  • White Papers // Jan 2011

    The Multi-Path Utility Maximization Problem

    In this paper, the authors study solutions to the multi-path utility maximization problem of the type in Optimizations of this type arise naturally in several networking problems such as the multi-path flow control problem. When the capacity of the network is large, it can also model the optimal QoS routing...

    Provided By Purdue University

  • White Papers // Jan 2011

    High Throughput Multicast Routing Metrics in Wireless Mesh Networks

    The stationary nature of nodes in a mesh network has shifted the main design goal of routing protocols from maintaining connectivity between source and destination nodes to finding high-throughput paths between them. In recent years, numerous link-quality-based routing metrics have been proposed for choosing high-throughput paths for unicast protocols. In...

    Provided By Purdue University

  • White Papers // Jan 2011

    Privacy Preserving Na?ve Bayes Classifier for Vertically Partitioned Data

    Privacy-Preserving Data Mining - developing models without seeing the data - is receiving growing attention. This paper assumes a privacy-preserving distributed data mining scenario: data sources collaborate to develop a global model, but must not disclose their data to others. Na?ve Bayes is often used as a baseline classifier, consistently...

    Provided By Purdue University

  • White Papers // Jan 2011

    EFW: A Cross-Layer Metric for Reliable Routing in Wireless Mesh Networks With Selfish Participants

    Wireless Mesh Networks (WMNs) have emerged as a flexible and low-cost network infrastructure, where heterogeneous mesh routers managed by different users collaborate to extend network coverage. Several routing protocols have been proposed to improve the packet delivery rate based on enhanced metrics that capture the wireless link quality. However, these...

    Provided By Purdue University

  • White Papers // Jul 2009

    Physically Restricted Authentication and Encryption for Cyber-Physical Systems

    Cyber-Physical Systems (CPS) are characterized by the close linkage of computational resources and physical devices. These systems can be deployed in a number of critical infrastructure settings. As a result, the security requirements of CPS are different than traditional computing architectures. For example, critical functions must be identified and isolated...

    Provided By Purdue University

  • White Papers // Jan 2011

    Sieve: A Tool for Automatically Detecting Variations Across Program Versions

    Software systems often undergo many revisions during their lifetime as new features are added, bugs repaired, abstractions simplified and refactored, and performance improved. When a revision, even a minor one, does occur, the changes it induces must be tested to ensure that invariants assumed in the original version are not...

    Provided By Purdue University

  • White Papers // May 2009

    Exceptionally Safe Futures

    A future is a well-known programming construct used to introduce concurrency to sequential programs. Computations annotated as futures are executed asynchronously and run concurrently with their continuations. Typically, futures are not transparent annotations: a program with futures need not produce the same result as the sequential program from which it...

    Provided By Purdue University

  • White Papers // Feb 2010

    Lightweight Checkpointing for Concurrent ML

    Transient faults that arise in large-scale software systems can often be repaired by re-executing the code in which they occur. Ascribing a meaningful semantics for safe re-execution in multithreaded code is not obvious, however. For a thread to re-execute correctly a region of code, it must ensure that all other...

    Provided By Purdue University

  • White Papers // Jan 2011

    Compression, Clustering and Pattern Discovery in Very High Dimensional Discrete-Attribute Datasets

    This paper presents an efficient framework for error-bounded compression of high-dimensional discrete-attribute datasets. Such datasets, which frequently arise in a wide variety of applications, pose some of the most significant challenges in data analysis. Sub-sampling and compression are two key technologies for analyzing these datasets. The proposed framework, PROXIMUS, provides...

    Provided By Purdue University

  • White Papers // Jan 2011

    PYTHIA-II: A Knowledge/Database System for Managing Performance Data and Recommending Scientific Software

    Often scientists need to locate appropriate software for their problems and then select from among many alternatives. The authors have previously proposed an approach for dealing with this task by processing performance data of the targeted software. This approach has been tested using a customized implementation referred to as PYTHIA....

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  • White Papers // Dec 2008

    How to Test DoS Defenses

    DoS defense evaluation methods influence how well test results predict performance in real deployment. This paper surveys existing approaches and criticizes their simplicity and the lack of realism. The authors summarize the work on improving DoS evaluation via development of standardized benchmarks and performance metrics. They end with guidelines on...

    Provided By Purdue University

  • White Papers // Jan 2010

    Ranking for Data Repairs

    Improving data quality is a time-consuming, labor-intensive and often domain specific operation. A recent principled approach for repairing dirty database is to use data quality rules in the form of database constraints to identify dirty tuples and then use the rules to derive data repairs. Most of existing data repair...

    Provided By Purdue University

  • White Papers // Mar 2010

    Optimizing Cost and Performance in Online Service Provider Networks

    The authors present a method to jointly optimize the cost and the performance of delivering traffic from an Online Service Provider (OSP) network to its users. The method, called Entact, is based on two key techniques. First, it uses a novel route-injection mechanism to measure the performance of alternative paths...

    Provided By Purdue University

  • White Papers // Mar 2010

    Building Reconstruction Using Manhattan-World Grammars

    The authors present a passive computer vision method that exploits existing mapping and navigation databases in order to automatically create 3D building models. The method defines a grammar for representing changes in building geometry that approximately follow the Manhattan-world assumption which states there is a predominance of three mutually orthogonal...

    Provided By Purdue University

  • White Papers // Jan 2010

    A Database-Centric Approach to Enabling EndtoEnd QoS for Multimedia Repositories

    The paper discusses the design and prototype implementation of a QoS aware multimedia database system. Recent research in multimedia databases has devoted little attention to the aspect of the integration of QoS support at the user level. One common scenario which the authors are concerned with connects a user through...

    Provided By Purdue University

  • White Papers // Jan 2010

    U-DBMS: A Database System for Managing Constantly-Evolving Data

    In many systems, sensors are used to acquire information from external environments such as temperature, pressure and locations. Due to continuous changes in these values, and limited resources e.g., network bandwidth and battery power, it is often infeasible for the database to store the exact values at all times. Queries...

    Provided By Purdue University

  • White Papers // Sep 2009

    Secure Network Coding for Wireless Mesh Networks: Threats, Challenges, and Directions

    In recent years, network coding has emerged as a new communication paradigm that can significantly improve the efficiency of network protocols by requiring intermediate nodes to mix packets before forwarding them. Recently, several real-world systems have been proposed to leverage network coding in wireless networks. Although the theoretical foundations of...

    Provided By Purdue University

  • White Papers // May 2010

    Characterizing Failures in Mobile OSes: A Case Study With Android and Symbian

    As smart phones grow in popularity, manufacturers are in a race to pack an increasingly rich set of features into these tiny devices. This brings additional complexity in the system software that has to fit within the constraints of the devices (chiefly memory, stable storage, and power consumption) and hence,...

    Provided By Purdue University

  • White Papers // Jan 2010

    On-the-Fly Intrusion Detection for Web Portals

    Remote access to distributed hyper-linked information proves to be one of the killer applications for computer networks. More and more content in current inter and intra nets is available as hyper-data, a form easing its distribution and semantic organization. In the framework of the Internet's Web-Portals and Pay-Sites, mechanisms for...

    Provided By Purdue University

  • White Papers // Apr 2010

    Security Issues in Structured Peer-to-Peer Networks

    Services in traditional networks (such as the internet) are typically based on the client-server model. Examples include web services provided by the web servers (such as the HTTPD servers) and the browsers that act as clients vis-a-vis the servers. Another common example would be the email servers that are in...

    Provided By Purdue University

  • White Papers // Dec 2008

    Human Resource Role In Work-Life Balance: A Case Of High Technology Knowledge Workers In Taiwan

    This paper involves the problems that young people in Taiwan are facing in high tech companies. Employees are spending many hours in their jobs and making high salaries as a result, but their social lives are suffering greatly. This paper examines the relationship between the work and social life of...

    Provided By Purdue University

  • White Papers // Dec 2008

    Loci: Simple Thread-Locality for Java

    This paper presents a simple type system for thread-local data in Java. Classes and types are annotated to express thread-locality and unintended leaks are detected at compile-time. The system, called Loci, is minimal, modular and compatible with legacy code. The only change to the language is the addition of two...

    Provided By Purdue University

  • White Papers // Dec 2008

    Energy-Efficient Peer-to-Peer Caching and Mobility Management in 4G Hybrid Networks

    Hybrid wireless networks are an integration of infrastructure-based (e.g. Cellular or Wireless LANs) and mobile ad hoc networks. They are emerging as an attractive solution to providing seamless mobile data services. However, performance of hybrid networks is severely impacted due to high energy consumption and uneven load distribution among nodes....

    Provided By Purdue University

  • White Papers // Jan 2010

    Distributed Clustering for Scalable, Long-Lived Sensor Networks

    Prolonged network lifetime, scalability, and load balancing are important requirements for many ad-hoc sensor network applications. To satisfy these requirements, several solutions have been proposed that exploit the tradeoffs among energy, accuracy, and latency. Many solutions also use hierarchical (tiered) architectures, where sensor nodes are clustered according to application-specific parameters....

    Provided By Purdue University

  • White Papers // Jan 2010

    Integrating Heterogeneous Wireless Technologies: A Cellular Aided Mobile Ad hoc Network (CAMA)

    A mobile ad hoc network is a collection of wireless terminals that can be deployed rapidly. Its deficiencies include limited wireless bandwidth efficiency, low throughput, large delays, and weak security. Integrating it with a well established cellular network can improve communication and security in ad hoc networks, as well as...

    Provided By Purdue University

  • White Papers // Nov 2008

    Security Vulnerabilities for Network Coding in Wireless Networks

    Network coding is a relatively new area of research which has been shown to have a large number of benefits over the routing and forwarding methods which are most commonly used today. Current work in network coding is most generally aimed toward achieving a higher effective throughput in wireless networks....

    Provided By Purdue University

  • White Papers // Jan 2010

    TCP over Wireless Links: Mechanisms and Implications

    In wireless networks, the implicit assumption which TCP makes that losses indicate network congestion is no longer valid. Losses in wireless networks can result from bit errors, fading and handoffs. There are two different approaches to improve TCP performance in case of wireless losses: (1) hide non-congestion-related losses from the...

    Provided By Purdue University

  • White Papers // Apr 2009

    Context-Dependent Authentication and Access Control

    As mobile computing continues to rise, users are increasingly able to connect to remote services from a wide range of settings. To provide this flexibility, security policies must be adaptive to the user's environment when the request is made. In the work, the authors define context to include the spatiotemporal...

    Provided By Purdue University

  • White Papers // Jan 2010

    On the Effectiveness of Movement Prediction To Reduce Energy Consumption in Wireless Communication

    Node movement can be exploited to reduce the energy consumption of wireless network communication. The strategy consists in delaying communication until a mobile node moves close to its target peer node, within an application-imposed deadline. The authors evaluate the performance of various heuristics that, based on the movement history of...

    Provided By Purdue University

  • White Papers // Oct 2009

    Covenant: An Architecture for Cooperative Scheduling in 802.11 Wireless Networks

    Wireless networks based on 802.11a/b/g protocols have gained wide-spread acceptance in both enterprise as well as home networks. However, these devices lack native support for many advanced features such as service differentiation, etc., that are required in specific application domains. In this paper, the authors propose Covenant, a software based...

    Provided By Purdue University

  • White Papers // Jan 2010

    Towards High-Throughput and Fair Multicast in Wireless Mesh Networks

    Wireless Mesh Networks (WMNs) have been proposed as an efficient solution for ubiquitous last-mile broadband access. In order to become a viable last-mile technology, WMNs must compete with existing broadband technologies, such as cable and DSL. In particular, WMNs have to meet two performance criteria: to provide high throughput in...

    Provided By Purdue University

  • White Papers // Feb 2009

    Strategic Planning White Paper: Extension And Engagement In The College Of Agriculture

    In this paper, the drivers of change, opportunities, and challenges that led to the development of these goals are first described, followed by the goals, strategies, and metrics. Nine drivers of change in Extension and Engagement programs were identified, and for each driver, opportunities resulting from the driver are identified,...

    Provided By Purdue University

  • White Papers // May 2010

    The Wage and Employment Effects of Outsourcing: Evidence From Danish Matched Worker-Firm Data

    The authors employ a unique matched worker firm dataset from Denmark to measure how importing and exporting shocks affect wages and employment at the firm and worker level. Using information on the specific products and origin/destination of trade for Danish firms, the authors construct instruments for the extent of importing...

    Provided By Purdue University

  • White Papers // Jan 2010

    Image-Based Transfer Function Design for Data Exploration in Volume Visualization

    Transfer function design is an integrated component in volume visualization and data exploration. The common trial-and-error approach for transfer function searching is a very difficult and time consuming process. A goal-oriented and parameterized transfer function model is, therefore, crucial in guiding the transfer function searching process for better and more...

    Provided By Purdue University