Purdue University

Displaying 1-40 of 202 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 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 // 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 // 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

    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...

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  • 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...

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  • 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,...

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  • 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,...

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  • 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...

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  • 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...

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  • 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...

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  • 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,...

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  • 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....

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  • 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...

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  • 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...

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  • 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...

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  • 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...

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  • 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

    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...

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  • 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

    Using Past Queries for Resource Selection in Distributed Information Retrieval

    Federated text search provides a unified search interface for multiple search engines of distributed text information sources. Resource selection is an important component for federated text search, which selects a small number of information sources that contain the largest number of relevant documents for a user query. Most prior research...

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  • White Papers // Jan 2011

    HighThroughput 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...

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  • White Papers // Dec 2009

    CCACK: Efficient Network Coding Based Opportunistic Routing Through Cumulative Coded Acknowledgments

    The use of random linear Network Coding (NC) has significantly simplified the design of Opportunistic Routing (OR) protocols by removing the need of coordination among forwarding nodes for avoiding duplicate transmissions. However, NC-based OR protocols face a new challenge: how many coded packets should each forwarder transmit? To avoid the...

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  • White Papers // Jan 2011

    CoCoA: Coordinated Cooperative Localization for Mobile Multi-Robot Ad Hoc Networks

    Mobile robot teams are particularly suited to applications where infrastructure is unavailable or damaged since they can be used to quickly form an infrastructure-less mobile ad hoc network performing tasks in a distributed manner. In such deployment scenarios, localization of individual robots is essential for enabling many applications. In this...

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  • White Papers // Jan 2011

    The Case for FEC-Based Reliable Multicast in Wireless Mesh Networks

    Many important applications in wireless mesh networks require reliable multicast communication. Previously, Forward Error Correction (FEC) techniques have been proved successful for providing reliability in the Internet, as they avoid the control packet implosion and scalability problems of ARQ-based protocols. In this paper, the authors examine if FEC can be...

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  • White Papers // Feb 2011

    Detecting Inconsistencies in Private Data With Secure Function Evaluation

    Erroneous and inconsistent data, often referred to as 'Dirty data', is a major worry for businesses. Prevalent techniques to improve data quality consist of discovering data quality rules, identifying records that violate those rules, and then modifying the data to either remove those violations. Most of the paper described in...

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  • White Papers // Mar 2011

    Query Processing in Private Data Outsourcing Using Anonymization

    The authors present a scheme for query processing in a private data outsourcing model. They assume that data is divided into identifying and sensitive data using an anatomy approach; only the client is able to reconstruct the original identifiable data. The key contribution of this paper is a relational query...

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  • White Papers // Jan 2011

    Network Similarity Decomposition (NSD): A Fast and Scalable Approach to Network Alignment

    As graph-structured datasets become commonplace, there is increasing need for efficient ways of analyzing such datasets. These analyses include conservation, alignment, differentiation, and discrimination, among others. When defined on general graphs, these problems are considerably harder than their well-studied counterparts on sets and sequences. This is a direct consequence of...

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  • White Papers // Jun 2010

    Isolates: Serializability Enforcement for Concurrent ML

    There has been much recent interest in exploring higher-level concurrency control abstractions such as Software Transactional Memory (STM) to alleviate the complexity of reasoning about interactions among concurrent threads of control. Isolation and atomicity are the two critical properties provided by an STM that guarantee serializability of concurrent actions. Isolation...

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  • White Papers // Apr 2010

    vSnoop: Improving TCP Throughput in Virtualized Environments Via Acknowledgement Offload

    Virtual Machine (VM) consolidation has become a common practice in clouds, Grids, and datacenters. While this practice leads to higher CPU utilization, the authors observe its negative impact on the TCP throughput of the consolidated VMs: As more VMs share the same core/CPU, the CPU is scheduling latency for each...

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  • White Papers // Mar 2010

    Lightweight Task Graph Inference for Distributed Applications

    Recent paradigm shifts in distributed computing such as the advent of cloud computing pose new challenges to the analysis of distributed executions. One important new characteristic is that the management staffs of computing platforms and the developers of applications are separated by corporate boundaries. The net result is that once...

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  • White Papers // Sep 2009

    Homomorphic Encryption Based k-out-of-n Oblivious Transfer Protocols

    Oblivious Transfer (OT) is an important cryptographic tool, which has found its usage in many crypto protocols, such as Secure Multiparty Computations [9], Certified E-mail and Simultaneous Contract Signing [20]. In this paper, the authors propose three k-OuT-of-n OT (OTn k) protocols based on additive homomorphic encryption. Two of these...

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  • White Papers // Sep 2009

    A Statistical Method for Integrated Data Cleaning and Imputation

    Real-world databases often contain both syntactic and semantic errors, in spite of integrity constraints and other safety measures incorporated into standard DBMSs. This is primarily due to the broad scope of incorrect data values that are difficult to fully express using the general types of constraints available. As a result...

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  • White Papers // Apr 2011

    On the Efficacy of Fine-Grained Traffic Splitting Protocols in Data Center Networks

    Multi-rooted tree topologies are commonly used to construct high-bandwidth data center network fabrics. In these networks, switches typically rely on Equal-Cost MultiPath (ECMP) routing techniques to split traffic across multiple paths, where each flow is routed through one of the available paths, but packets within a flow traverse the same...

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  • White Papers // Mar 2011

    c-Lock: Dynamic Lock-Coalescing for Latency-Sensitive Distributed Locking

    Transactional updates to groups of keys are common to a wide class of distributed systems, spanning MapReduce-basedworkloads, distributed key-value stores and conventional distributed object databases. Such updates are typically implemented using nested transactions/ locks. The cost of such updates is critically dependent on the nesting depth, the contention on any...

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  • White Papers // Oct 2010

    Generalizations With Probability Distributions for Data Anonymization

    Anonymization-based privacy protection ensures that data cannot be traced to an individual. To this end, an anonymizer faces two challenges. First, the output anonymization must satisfy the underlying privacy definition and second, the anonymization needs to contain as much information as possible. One way to address the latter challenge has...

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  • White Papers // Jul 2010

    Revisiting Overlay Multicasting for the Cloud

    Group communication systems (e.g., multicast, DHTs) have emerged as basic primitives for several large-scale distributed systems. Most existing systems that implement these primitives often assume a flat topology of overlay nodes. For instance, many DHTs assume that all overlay links are often homogeneous in their capacities, costs and other such...

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  • White Papers // Oct 2010

    Memory Indexing and its Use in Automated Debugging

    Execution comparison examines different executions generated by different program versions, different inputs, or by perturbations. It has a wide range of applications in debugging, regression testing, program comprehension, and security. Meaningful comparison demands that executions are aligned before they are compared, otherwise the resulting differences do not reflect semantic differences....

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  • White Papers // Jan 2011

    The Fundamental Capacity-Delay Tradeoff in Large Mobile Ad Hoc Networks

    In this paper, the authors have studied the fundamental capacity-delay tradeoff in mobile ad hoc networks under the i.i.d. mobility model. Their contributions are threefold. The authors have established the upper bound on the optimal capacity-delay tradeoff over all causal scheduling policies. The upper bound not only provides the fundamental...

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  • 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 // Jan 2011

    Radiating Sensor Selection for Distributed Beamforming in Wireless Sensor Networks

    Collaborative beamforming has already demonstrated its potential of significant power savings in distributed sensor networks. In collaborative beamforming, the antennas of the sensor nodes form a distributed antenna array in an effort to direct the radiated energy to the desired direction and thus increase the overall power efficiency of the...

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  • White Papers // Jan 2011

    XCOR: Synergistic Interflow Network Coding and Opportunistic Routing

    In the past few years, a plethora of new routing protocols have been proposed that improve the throughput of Wireless Mesh Networks (WMNs). Two of the building blocks shown to achieve significant performance benefits are Opportunistic Routing (OR) and interflow Network Coding (NC), both exploiting the broadcast nature of the...

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  • White Papers // Aug 2009

    Designing Coded Feedback for Efficient Network Coding Based Opportunistic Routing

    Opportunistic Routing (OR) is a new routing paradigm for improving throughput in lossy Wireless Mesh Networks (WMNs). In OR, a set of nodes in a belt around a routing path (i.e., the forwarding nodes or FNs) collaboratively forward packets from the source to the destination. A major challenge in OR...

    Provided By Purdue University

  • White Papers // Nov 2010

    ACConv - An Access Control Model for Conversational Web Services

    Inter-operation among different organizations is today a pressing need. Governmental, military, financial, medical and private institutions increasingly participate to distributed collaborative infrastructures. Hence, distributed, heterogeneous systems are becoming very common, as globalized organizations integrate applications running on different platforms. As a consequence, there is a growing demand for architectures and...

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  • White Papers // Oct 2009

    A Privacy-Preserving Approach to Policy-Based Content Dissemination

    The authors propose a novel scheme for selective distribution of content, encoded as documents, that preserves the privacy of the users to whom the documents are delivered and is based on an efficient and novel group key management scheme. Their document broadcasting approach is based on access control policies specifying...

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  • White Papers // Jan 2011

    Verification of Access Control Requirements in Web Services Choreography

    Web services choreography is used to design peer-to-peer applications where each peer is potentially a Web service. It defines the required behavior of participating Web services along with their interactions through message exchanges. Implementing a complex system described by choreography requires selecting actual Web services whose individual behaviors are compatible...

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  • White Papers // Jan 2011

    Security in Wireless Sensor Networks a Layer-Based Classification

    With a widespread growth in the potential applications of Wireless Sensor Networks (WSN), the need for reliable security mechanisms for them has increased manifold. Security protocols in WSNs, unlike the traditional mechanisms, need special efforts and issues to be addressed. This is attributed to the inherent computational and communicational constraints...

    Provided By Purdue University

  • White Papers // Jan 2011

    Trust-Based Privacy Preservation for Peer-to-Peer Data Sharing

    Privacy preservation in a peer-to-peer system tries to hide the association between the identity of a participant and the data that it is interested in. The authors propose a trust-based privacy preservation method for peer-to-peer data sharing. It adopts the trust relation between a peer and its collaborators (buddies). The...

    Provided By Purdue University

  • White Papers // Jan 2011

    Verification of Database Transaction Lock Management in the Presence of Role Based Access Control Policy

    In a computing environment where access to system resources is controlled by an access control policy and execution of database transactions is dictated by database locking policy, interaction between the two policies can result in constraints restricting execution of transactions. The authors present a methodology for the verification of database...

    Provided By Purdue University

  • White Papers // Sep 2009

    Peer-To-Peer Video on Demand: Challenges and Solutions

    The challenges and solutions required for Peer-To-Peer Video-on-Demand (P2P VoD) provided by a fixed provider such as a cable company are fundamentally different from those seen in traditional P2P networks or client-server VoD solutions. Unlike traditional P2P networks, the end nodes (set top boxes with DVR capabilities) are largely under...

    Provided By Purdue University

  • White Papers // Feb 2010

    Multicore-Aware Reuse Distance Analysis

    This paper presents and validates methods to extend reuse distance analysis of application locality characteristics to shared-memory multicore platforms by accounting for invalidation-based cache-coherence and inter-core cache sharing. Existing reuse distance analysis methods track the number of distinct addresses referenced between reuses of the same address by a given thread,...

    Provided By Purdue University

  • White Papers // Jan 2011

    SECOS: Key Management for Scalable and Energy Efficient Crypto on Sensors

    Wireless sensor networks are becoming a critical computational infrastructure, in which the communication between nodes needs to be protected from eavesdropping and tampering. Symmetric key cryptography is the fundamental technique being used. The protocols in this domain suffer from one or more of the problems of weak security guarantees if...

    Provided By Purdue University

  • White Papers // Jan 2011

    Trust, Risk and Economic Benefits in Online Environments

    Lack of trust is identified as one of the main constraints on online environments, particularly in terms of consumer protection. Although the elements that contribute to building trust can be identified in broad terms, there are still many uncertainties in defining and establishing trust in online environments. This paper investigates...

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  • White Papers // Jan 2011

    Information Leaks and Safe Web Services

    The paper shows that information leaks are inherent in object models based on subtyping and inclusion polymorphism. Web services interact with other systems across organizational boundaries using such an object model. In the context of web services, information leaks pose serious security and privacy concerns. A safe web service is...

    Provided By Purdue University

  • White Papers // Jan 2011

    Policy-Based Verification of Distributed Workflows in a Multi-Domain Environment

    There is a growing need to support secure interaction among autonomous domains/systems for developing distributed applications. As domains operate according to their individual security and access control policies, supporting secure interactions among domains for distributed workflows is a complex task prone to subtle errors that can have serious security implications....

    Provided By Purdue University

  • White Papers // Jan 2011

    FaultMiner: Discovering Unknown Software Defects Using Static Analysis and Data Mining

    Improving software assurance is of paramount importance given the impact of software on the lives. Static and dynamic approaches have been proposed over the years to detect security vulnerabilities. These approaches assume that the signature of a defect, for instance the use of a vulnerable library function, is known apriori....

    Provided By Purdue University

  • White Papers // Jan 2011

    Collapsar: A VM-Based Honeyfarm and Reverse Honeyfarm Architecture for Network Attack Capture and Detention

    The honeypot has emerged as an effective tool to provide insights into new attacks and exploitation trends. However, a single honeypot or multiple independently operated honeypots only provide limited local views of network attacks. Coordinated deployment of honeypots in different network domains not only provides broader views, but also creates...

    Provided By Purdue University