Purdue University

Displaying 1-40 of 201 results

  • White Papers // Dec 2014

    On Order-Independent Semantics of the Similarity Group-By Relational Database Operator

    Similarity Group-By (SGB) has been proposed as a relational database operator to match the needs of emerging database applications. Many SGB operators that extend SQL have been proposed in the literature, e.g., similarity operators in the one-dimensional space. These operators have various semantics. Depending on how these operators are implemented,...

    Provided By Purdue University

  • 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

    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 // 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 // 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...

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  • 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 // Jan 2010

    Threat Modelling for SQL Servers: Designing a Secure Database in a Web Application

    This paper presents the results from an analysis focusing on security threats that can arise against an SQL server when included in Web application environments. The approach used is based on the STRIDE classification methodology. The results presented provide also some general guidelines and countermeasures against the different attacks that...

    Provided By Purdue University

  • White Papers // Jan 2011

    VIOLIN: Virtual Internetworking on Overlay Infrastructure

    The authors propose a novel application-level virtual network architecture called VIOLIN (Virtual Internetworking on OverLay INfrastructure). VIOLINs are isolated virtual networks created on top of an overlay infrastructure (e.g., PlanetLab). Entities in a VIOLIN include virtual end-hosts, routers, and switches implemented by software and hosted by physical overlay hosts. Novel...

    Provided By Purdue University

  • White Papers // Jan 2011

    SigGraph: Brute Force Scanning of Kernel Data Structure Instances Using Graph-Based Signatures

    Brute force scanning of kernel memory images for finding kernel data structure instances is an important function in many computer security and forensics applications. Brute force scanning requires effective, robust signatures of kernel data structures. Existing approaches often use the value invariants of certain fields as data structure signatures. However,...

    Provided By Purdue University

  • White Papers // Nov 2009

    E-Personalization And Online Privacy Features: The Case With Travel Websites

    E-personalization is the process of tailoring preferences to individual traveler's characteristics or performance on travel websites. E-personalization is used to enhance customer service or e-commerce sales. However, personalization also causes privacy concerns. Today's technology provides multiple opportunities for extensive data gathering and invasion of privacy. Privacy issue has recently received...

    Provided By Purdue University

  • White Papers // Jan 2010

    Preventing Multi-Query Attack in Location-Based Services

    Despite increasing popularity, Location-Based Services (LBS) (e.g., searching nearby points-of-interest on map) on mobile handheld devices have been subject to major privacy concerns for users. The existing third-party privacy protection methods hide the exact location of users from service providers by sending Cloaking Regions (CR) that contain several other user...

    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 // Jan 2011

    VioCluster: Virtualization for Dynamic Computational Domains

    A large organization, such as a university, commonly supplies computational power through multiple independently administered computational domains (e.g. Clusters). Each computational domain faces the conflict between dynamic workload and static capacity. This is clearly inefficient at times when some clusters have idle nodes while others experience excessive workload. An opportunity...

    Provided By Purdue University

  • White Papers // Sep 2010

    Trust Based Security for Cloud Systems

    Even though Security, Privacy and Trust issues exists since the evolution of Internet, the reason why they are widely spoken these days is because of the Cloud Computing scenario. Any client/small organization/enterprise that processes data in the cloud is subjected to an inherent level of risk because outsourced services bypass...

    Provided By Purdue University

  • White Papers // Aug 2010

    Protection of Identity Information in Cloud Computing Without Trusted Third Party

    Cloud computing allows the use of Internet-based services to support business processes and rental of IT-services on a utility-like basis. It offers a concentration of resources but also poses risks for data privacy. A single breach can cause significant loss. The heterogeneity of "Users" represents a danger of multiple, collaborative...

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  • White Papers // Jan 2011

    Heterogeneous Distributed Computing

    One of the biggest challenges with high-performance computing is that as machine architectures become more advanced to obtain increased peak performance, only a small fraction of this performance is achieved on many real application sets. This is because a typical application may have various subtasks with different architectural requirements. When...

    Provided By Purdue University

  • White Papers // Jan 2010

    A Secure Programming Paradigm for Network Virtualization (Invited Paper)

    The central paradigm of today's successful Internet is to keep the network core simple and move complexity towards the network end points. Unfortunately, this very paradigm limits network management and control capabilities, and creates opportunities for attacks such as worms, viruses, and spam that often seriously disrupt and degrade Internet...

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  • White Papers // Aug 2010

    3D Rendering of American Sign Language Finger-Spelling: A Comparative Study of Two Animation Techniques

    In this paper the authors report a study aimed at determining the most effective animation technique for representing ASL (American Sign Language) finger-spelling. Specifically, in the study The authors compare two commonly used 3D computer animation methods (keyframe animation and motion capture) in order to ascertain which technique produces the...

    Provided By Purdue University

  • White Papers // Sep 2009

    A General Framework for Web Content Filtering

    Web content filtering is a means to make end-users aware of the 'Quality' of Web resources by evaluating their contents and/or characteristics against users' preferences. Although they can be used for a variety of purposes, Web content filtering tools are mainly deployed as a service for parental control purposes, and...

    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...

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  • White Papers // Jan 2011

    Overlay Node Placement: Analysis, Algorithms and Impact on Applications

    Overlay routing has emerged as a promising approach to improving performance and reliability of Internet paths. To fully realize the potential of overlay routing under the constraints of deployment costs in terms of hardware, network connectivity and human effort, it is critical to carefully place infrastructure overlay nodes to balance...

    Provided By Purdue University

  • White Papers // Sep 2009

    Evaluating Statistical Tests for Within-Network Classifiers of Relational Data

    Recently a number of modeling techniques have been developed for data mining and machine learning in relational and network domains where the instances are not independent and identically distributed (i.i.d.). These methods specifically exploit the statistical dependencies among instances in order to improve classification accuracy. However, there has been little...

    Provided By Purdue University

  • White Papers // Jun 2010

    Combining Semi-Supervised Learning and Relational Resampling for Active Learning in Network Domains

    Recent work in statistical relational learning has demonstrated the effectiveness of network-based classification methods, which exploit relational dependencies among in-stances to improve predictions. These methods have been applied in a broad range of domains, from bioinformatics to fraud detection. Although labeled training examples can be costly to acquire in these...

    Provided By Purdue University

  • White Papers // Dec 2009

    Predicting Prefix Availability in the Internet

    The Border Gateway Protocol (BGP) maintains inter-domain routing information by announcing and withdrawing IP prefixes, which may result in prefix unreachability. Prefix availability observed from different vantage points in the Internet can be lower than standards promised by Service Level Agreements (SLAs). In this paper, the authors develop a framework...

    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...

    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....

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  • White Papers // Oct 2009

    On the Large-Deviations Optimality of Scheduling Policies Minimizing the Drift of a Lyapunov Function

    The authors show that for a large class of scheduling algorithms, when the algorithm minimizes the drift of a Lyapunov function, the algorithm is optimal in maximizing the asymptotic decay-rate of the probability that the Lyapunov function value exceeds a large threshold. The result in this paper extends the prior...

    Provided By Purdue University

  • White Papers // Jan 2011

    Joint Rate Control and Scheduling in Multihop Wireless Networks

    The authors study the joint problem of allocating data rates and finding a stabilizing scheduling policy in a multi-hop wireless network. They propose a dual optimization based approach through which the rate control problem and the scheduling problem can be decomposed. The authors demonstrate via both analytical and numerical results...

    Provided By Purdue University

  • White Papers // Jan 2011

    Constant-Time Distributed Scheduling Policies for Ad Hoc Wireless Networks

    The authors propose two new distributed scheduling policies for ad hoc wireless networks that can achieve provable capacity regions. Known scheduling policies that guarantee comparable capacity regions are either centralized or need computation time that increases with the size of the network. In contrast, the unique feature of the proposed...

    Provided By Purdue University

  • White Papers // Oct 2009

    On the Queue-Overflow Probabilities of Distributed Scheduling Algorithms

    In this paper, the authors are interested in using large deviations theory to characterize the asymptotic decay-rate of the queue-overflow probability for distributed wireless scheduling algorithms, as the overflow threshold approaches infinity. They consider ad-hoc wireless networks where each link interferes with a given set of other links, and they...

    Provided By Purdue University

  • White Papers // Mar 2010

    Low-Complexity Scheduling Algorithm for Sum-Queue Minimization in Wireless Convergecast

    The authors consider the problem of link scheduling for efficient converge-cast in a wireless system. While there have been many results on scheduling algorithms that attain the maximum possible throughput in such a system, there has been few results that provide scheduling algorithms that are optimal in terms of some...

    Provided By Purdue University

  • White Papers // Jun 2010

    On the Queue-Overflow Probabilities of a Class of Distributed Scheduling Algorithms

    In this paper, the authors use large-deviations theory to characterize the asymptotic decay-rate of the queue-overflow probability for distributed wireless scheduling algorithms, as the overflow threshold approaches infinity. They consider ad-hoc wireless networks where each link interferes with a given set of other links, and they focus on a distributed...

    Provided By Purdue University

  • White Papers // Jan 2011

    Low-Complexity and Distributed Energy Minimization in Multi-Hop Wireless Networks

    In this paper, the authors study the problem of minimizing the total power consumption in a multi-hop wireless network subject to a given offered load. It is well-known that the total power consumption of multi-hop wireless networks can be substantially reduced by jointly optimizing power control, link scheduling, and routing....

    Provided By Purdue University

  • White Papers // Jan 2011

    A Distributed Joint Channel-Assignment, Scheduling and Routing Algorithm for Multi-Channel Ad Hoc Wireless Networks

    The capacity of ad hoc wireless networks can be substantially increased by equipping each network node with multiple radio interfaces that can operate on multiple non-overlapping channels. However, new scheduling, channel assignment, and routing algorithms are required to fully utilize the increased bandwidth in multi-channel multi-radio ad hoc networks. In...

    Provided By Purdue University

  • 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

    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....

    Provided By Purdue University

  • White Papers // Apr 2010

    Web Security: PHP Exploits and the SQL Injection Attack

    Web security goes beyond the concerns that have been presented so far. Web security addresses the issues that are specific to how web servers present their content to web browsers, how the browsers interact with the servers, and how people interact with the browsers. Until about a decade ago, the...

    Provided By Purdue University

  • White Papers // Jan 2011

    Location-Based e-Campus Web Services: From Design to Deployment

    In THE previous work, the authors have designed, using a network-based approach, and are currently deploying on Purdue wireless Infrastructure, a Web service for location discovery of 802.11-based mobile devices. This paper presents a novel web-based application called Remote Printing Service (RPS) which is entirely built on top of the...

    Provided By Purdue University

  • White Papers // Feb 2010

    Flood Mapping With Satellite Images and Its Web Service

    The value and usefulness of timely collected and processed satellite images are demonstrated through the mapping activities in recent floods in Indiana and Georgia. In addition to the free Landsat images, which have limitations in timely revisits and cloud cover requirements, the other images, such as radar images, from the...

    Provided By Purdue University

  • White Papers // Jan 2011

    Scaling Byzantine Fault-Tolerant Replication to Wide Area Networks

    This paper presents the first hierarchical Byzantine fault-tolerant replication architecture suitable to systems that span multiple wide area sites. The architecture confines the effects of any malicious replica to its local site, reduces message complexity of wide area communication, and allows read-only queries to be performed locally within a site...

    Provided By Purdue University