University of Illinois

Displaying 1-40 of 293 results

  • White Papers // Sep 2013

    Factoring RSA Keys From Certified Smart Cards: Coppersmith in the Wild

    In this paper, the authors explain how an attacker can efficiently factor 184 distinct RSA keys out of more than two million 1024-bit RSA keys downloaded from Taiwan's national \"Citizen digital certificate\" database. These keys were generated by government-issued smart cards that have built-in hardware random-number generators and that are...

    Provided By University of Illinois

  • White Papers // Aug 2013

    Generation of Control and Data Flow Graphs from Scheduled and Pipelined Assembly Code

    High-level synthesis tools generally convert abstract designs described in a high-level language into a Control and Data Flow Graph (CDFG), which is then optimized and mapped to hardware. However, there has been little work on generating CDFGs from highly pipelined software binaries, which complicate the problem of determining data flow...

    Provided By University of Illinois

  • White Papers // Jun 2013

    Authentication in Ethos

    The abstractions used to provide Operating System (OS) authentication are fundamental to a system's security. Authentication primitives should be simple, general, and robust against attack. The authors describe the authentication mechanisms of Ethos, an experimental, clean-slate operating system that has been designed for security. They reexamine and redesign software layering...

    Provided By University of Illinois

  • White Papers // May 2013

    MinimaLT: Minimal-latency Networking Through Better Security

    Minimal Latency Tunneling (MinimaLT) is a new network protocol that provides ubiquitous encryption for maximal confidentiality, including protecting packet headers. MinimaLT provides server and user authentication, extensive Denial-of-Service protections, and IP mobility while approaching perfect forward secrecy. The authors describe the protocol, demonstrate its performance relative to TLS and unencrypted...

    Provided By University of Illinois

  • White Papers // Dec 2012

    WAVES: Automatic Synthesis of Client-Side Validation Code for Web Applications

    The current practice of web application development treats the client and server components of the application as two separate but interacting pieces of software. Each component is written independently, usually in distinct programming languages and development platforms - a process known to be prone to errors when the client and...

    Provided By University of Illinois

  • White Papers // Sep 2012

    Faster Batch Forgery Identification

    The authors' goal in this paper is to minimize the cost of elliptic-curve signature verification. Batch signature verification detects whether a batch of signatures contains any forgeries. Batch forgery identification pinpoints the location of each forgery. Existing forgery-identification schemes vary in their strategies for selecting sub-batches to verify (individual checks,...

    Provided By University of Illinois

  • White Papers // Sep 2012

    Computing Small Discrete Logarithms Faster

    Computations of small discrete logarithms are feasible even in "Secure" groups, and are used as subroutines in several cryptographic protocols in the literature. For example, the Boneh-Goh-Nissim degree- 2-homomorphic public-key encryption system uses generic square-root discrete-logarithm methods for decryption. This paper shows how to use a small group-specific table to...

    Provided By University of Illinois

  • White Papers // Sep 2012

    SipHash: A Fast Short-Input PRF

    SipHash is a family of pseudorandom functions optimized for short inputs. Target applications include network traffic authentication and hash-table lookups protected against hash-flooding denial-of-service attacks. SipHash is simpler than MACs based on universal hashing, and faster on short inputs. Compared to dedicated designs for hash-table lookup, SipHash has well-defined security...

    Provided By University of Illinois

  • White Papers // Aug 2012

    Optimal Cooperative Spectrum Sensing in Cognitive Radio with Taguchi Method

    Spectrum sensing is an essential topic in cognitive radio networks to detect primary users. Cooperative spectrum sensing with linear fusion scheme is studied in multiband channel systems. The problem turns out to be a non-convex optimization problem in general with thresholds of the energy detectors and the weights of linear...

    Provided By University of Illinois

  • White Papers // Jun 2012

    Two-Way Networks: When Adaptation Is Useless

    Most wireless communication networks are two-way, where nodes act as both sources and destinations of messages. This allows for "Adaptation" at or "Interaction" between the nodes - a node's channel inputs may be functions of its message(s) and previously received signals, in contrast to feedback-free one-way channels where inputs are...

    Provided By University of Illinois

  • White Papers // Jun 2012

    Never Trust a Bunny

    Lapin is a lightweight "RFID authentication" system introduced at FSE 2012. The system is claimed to be "Provably Secure Against Active Attacks". This claim is qualified elsewhere in: attacking Lapin-n is provably as difficult as attacking an n-bit "Ring-LPN" problem introduced in the same paper. "Lapin" is a new RFID...

    Provided By University of Illinois

  • White Papers // May 2012

    On the Capacity of Multi-User Two-Way Linear Deterministic Channels

    In multi-user two-way channels nodes are both sources and destinations of messages. This allows for "Adaptation" at or "Interaction" between the nodes - the next channel inputs may be a function of the past received signals at a particular node. How to best adapt is key to two-way communication problems,...

    Provided By University of Illinois

  • White Papers // May 2012

    Exploiting Opportunistic Overhearing to Improve Performance of Mutual Exclusion in Wireless Ad Hoc Networks

    The authors design two mutual exclusion algorithms for wireless networks. Their mutual exclusion algorithms are distributed token based algorithms which exploit the opportunistic message overhearing in wireless networks. One of the algorithms is based on overhearing of token transmission. In the other algorithm, overhearing of both token and request messages...

    Provided By University of Illinois

  • White Papers // May 2012

    The Sum-Capacity of the Linear Deterministic Three-User Cognitive Interference Channel

    Inspired by cognitive networks, the authors consider the linear deterministic three-user cognitive interference channel with one primary and two secondary/cognitive transmitters which approximates the Gaussian channel at high SNR. Outer bounds on the sum-rate are derived and matching transmission schemes are provided in all interference regimes, thereby completely characterizing the...

    Provided By University of Illinois

  • White Papers // May 2012

    Waveform Scheduling Via Directed Information in Cognitive Radar

    The objective of waveform scheduling is to achieve maximal information extraction of the radar scene, which typically changes from one measurement to the next, by exploiting prior statistics and waveform diversity. In this paper waveform scheduling is addressed using information theoretic concepts. A pre-defined waveform library is assumed to be...

    Provided By University of Illinois

  • White Papers // Apr 2012

    Defining the Undefinedness of C

    This paper investigates undefined behavior in C and offers a few simple techniques for operationally specifying such behavior formally. A semantics-based undefinedness checker for C is developed using these techniques, as well as a test suite of undefined programs. The tool is evaluated against other popular analysis tools, using the...

    Provided By University of Illinois

  • White Papers // Apr 2012

    An Architecture for Dynamic Service-Oriented Computing in Networked Embedded Systems

    Software development in real-time and embedded systems has traditionally focused on stand-alone applications with static models for scheduling and resource allocation. The authors' goal is to facilitate the development of embedded applications in an open system, where tasks and resources arrive and leave dynamically, and their execution is concurrent. They...

    Provided By University of Illinois

  • White Papers // Apr 2012

    Algorithmic Approaches to Low Overhead Fault Detection for Sparse Linear Algebra

    The increasing size and complexity of High-Performance Computing systems is making it increasingly likely that individual circuits will produce erroneous results, especially when operated in a low energy mode. Previous techniques for Algorithm - Based Fault Tolerance (ABFT) have been proposed for detecting errors in dense linear operations, but have...

    Provided By University of Illinois

  • White Papers // Apr 2012

    Scoped Synchronization Constraints for Large Scale Actor Systems

    Very large scale systems of autonomous concurrent objects (Actors) require coordination models to meet two competing goals. On the one hand, the coordination models must allow Actors to dynamically modify protocols in order to adapt to requirement changes over the, likely extensive, lifetime of the system. On the other hand,...

    Provided By University of Illinois

  • White Papers // Apr 2012

    Scalable Parametric Runtime Monitoring

    Run-time monitoring is an effective means to improve the reliability of systems. In recent years, parametric monitoring, which is highly suitable for object-oriented systems, has gained significant traction. Previous work on the performance of parametric run-time monitoring has focused on the performance of monitoring only one specification at a time....

    Provided By University of Illinois

  • White Papers // Mar 2012

    JavaMOP: Efficient Parametric Runtime Monitoring Framework

    Runtime monitoring is a technique usable in all phases of the software development cycle, from initial testing, to debugging, to actually maintaining proper function in production code. Of particular importance are parametric monitoring systems, which allow the specification of properties that relate objects in a program, rather than only global...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Usable Assembly Language for GPUs: A Success Story

    The NVIDIA compilers nvcc and ptxas leave the programmer with only very limited control over register allocation, register spills, instruction selection, and instruction scheduling. In theory a programmer can gain control by writing an entire kernel in van der Laan's cudasm assembly language, but this requires tedious, error-prone tracking of...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Non-Blind Watermarking of Network Flows

    Linking network flows is an important problem in intrusion detection as well as anonymity. Passive traffic analysis can link flows but requires long periods of observation to reduce errors. Active traffic analysis, also known as flow watermarking, allows for better precision and is more scalable. Previous flow watermarks introduce significant...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Self-Partitioning Cloud Datastore for Scalable Transaction Processing Proposal

    The authors are designing a new cloud data storage system that will be highly scalable and yet still be able to provide strong data consistency guarantees. Their system extends existing cloud key/value stores with modular components for transaction management and access-based partitioning. They plan to utilize graph theory, clustering algorithms,...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Maximum Likelihood Time Delay Estimation and Cramer-Rao Bounds for Multipath Exploitation

    In this paper, time delay estimation using the maximum likelihood principle is addressed for the multipath exploitation problem, and the corresponding Cramer-Rao bounds are derived. A single wideband radar, and a target in a known reflecting geometry are assumed. If the multipath is indeed detectable and resolvable, it is shown...

    Provided By University of Illinois

  • White Papers // Mar 2012

    OSA: An Optical Switching Architecture for Data Center Networks With Unprecedented Flexibility

    Data Center Networks (DCNs) form the backbone infrastructure of many large-scale enterprise applications as well as emerging cloud computing providers. This paper describes the design, implementation and evaluation of OSA, a novel optical switching architecture for DCNs. Leveraging runtime reconfigurable optical devices, OSA dynamically changes its topology and link capacities,...

    Provided By University of Illinois

  • White Papers // Mar 2012

    From Hoare Logic to Matching Logic

    Matching logic has been recently proposed as an alternative program verification approach. Unlike Hoare logic, where one defines a language-specific proof system that needs to be proved sound for each language separately, matching logic provides a language-independent and sound proof system that directly uses the trusted operational semantics of the...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Towards Categorizing and Formalizing the JDK API

    Formal specification of correct library usage is extremely useful, both for software developers and for the formal analysis tools they use, such as model checkers or runtime monitoring systems. Unfortunately, the process of creating formal specifications is time consuming, and, for the most part, even the libraries in greatest use,...

    Provided By University of Illinois

  • White Papers // Feb 2012

    Making Maude Definitions More Interactive

    This paper presents an interface for achieving interactive executions of Maude terms by allowing console and file Input/Output (I/O) operations. This interface consists of a Maude API for I/O operations, a Java-based server offering I/O capabilities, and a communication protocol between the two implemented using the external objects concept and...

    Provided By University of Illinois

  • White Papers // Feb 2012

    On the Capacity of the Symmetric Interference Channel With a Cognitive Relay at High SNR

    The capacity of the Interference Channel with Cognitive Relay, a channel model which generalizes the broadcast, interference and cognitive interference channels, is still an open question. To make progress towards understanding this complex channel, the authors first consider the binary linear deterministic models that approximate the Gaussian channel at high...

    Provided By University of Illinois

  • White Papers // Feb 2012

    Token-DCF: An Opportunistic MAC Protocol for Wireless Networks

    IEEE 802.11 DCF is the MAC protocol currently used in wireless LANs. 802.11 DCF is inefficient due to two types of overhead; channel idle time and collision time. This paper presents the design and performance evaluation of an efficient MAC protocol for wireless networks, called Token-DCF. Token-DCF decreases both idle...

    Provided By University of Illinois

  • White Papers // Feb 2012

    Towards a Unified Theory of Operational and Axiomatic Semantics

    This paper presents a nine-rule language-independent proof system that takes an operational semantics as axioms and derives program properties, including ones corresponding to Hoare triples. This eliminates the need for language-specific Hoare-style proof rules in order to verify programs, and, implicitly, the tedious step of proving such proof rules sound...

    Provided By University of Illinois

  • White Papers // Jan 2012

    Optimizing Quality-of-Information in Cost-Sensitive Sensor Data Fusion

    This paper investigates maximizing quality of information subject to cost constraints in data fusion systems. The authors consider data fusion applications that try to estimate or predict some current or future state of a complex physical world. Examples include target tracking, path planning, and sensor node localization. Rather than optimizing...

    Provided By University of Illinois

  • White Papers // Jan 2012

    Evaluating Polynomials in Several Variables and Their Derivatives on a GPU Computing Processor

    In order to obtain more accurate solutions of polynomial systems with numerical continuation methods the users use multiprecision arithmetic. Their goal is to offset the overhead of double arithmetic accelerating the path trackers and in particular Newton's method with a general purpose graphics processing unit. In this paper, the authors...

    Provided By University of Illinois

  • White Papers // Jan 2012

    Service Composition for Advanced Multimedia Applications

    By composing distributed, autonomous services dynamically to provide new functionalities, service composition provides an attractive way for customized multimedia content production and delivery. Previous research work has addressed various aspects of service composition such as composibility, QoS-awareness, and load balancing. However, most of the work has focused on applications where...

    Provided By University of Illinois

  • White Papers // Jan 2012

    Enforcing Alias Analysis for Weakly Typed Languages

    Static analysis of programs in weakly typed languages such as C and C++ is generally not sound because of possible memory errors due to dangling pointer references, uninitialized pointers, and array bounds overflow. Optimizing compilers can produce unpredictable results when such errors occur, but this is quite undesirable for many...

    Provided By University of Illinois

  • White Papers // Dec 2011

    Making DTNs Robust Against Spoofing Attacks With Localized Countermeasures

    In this paper, the authors propose countermeasures to mitigate damage caused by spoofing attacks in Delay-Tolerant Networks (DTNs). In their model, an attacker spoofs someone else's address (the victim's) to absorb packets from the network intended for that victim. Address spoofing is arguably a very severe attack in DTNs, compared...

    Provided By University of Illinois

  • White Papers // Dec 2011

    Tiresias: Online Anomaly Detection for Hierarchical Operational Network Data

    Operational network data, management data such as customer care call logs and equipment system logs, is a very important source of information for network operators to detect problems in their networks. Unfortunately, there is lack of efficient tools to automatically track and detect anomalous events on operational data, causing ISP...

    Provided By University of Illinois

  • White Papers // Dec 2011

    Capacity of Byzantine Consensus in Capacity Limited Point-to-Point Networks

    In this paper, the authors investigate the problem of maximizing the throughput, i.e., achieving capacity, of Byzantine consensus in point-to-point networks, in which each link has a capacity constraint. They derive an upper bound of the capacity of consensus in general point-to-point networks, and prove its tightness in 4-node complete...

    Provided By University of Illinois

  • White Papers // Dec 2011

    The Security Impact of a New Cryptographic Library

    This paper introduces a new cryptographic library, NaCl, and explains how the design and implementation of the library avoid various types of cryptographic disasters suffered by previous cryptographic libraries such as OpenSSL. For most cryptographic operations there exist widely accepted standards, such as the Advanced Encryption Standard (AES) for secret-key...

    Provided By University of Illinois

  • White Papers // Mar 2011

    Matching Logic: An Alternative to Hoare/Floyd Logic

    This paper introduces matching logic, a novel framework for defining axiomatic semantics for programming languages, inspired from operational semantics. Matching logic specifications are particular first-order formulae with constrained algebraic structure, called patterns. Program configurations satisfy patterns iff they match their algebraic structure and satisfy their constraints. Using a simple IMPerative...

    Provided By University of Illinois

  • White Papers // May 2010

    A Formal Executable Semantics of Verilog

    This paper describes a formal executable semantics for the Verilog hardware description language. The goal of the authors' formalization is to provide a concise and mathematically rigorous reference augmenting the prose of the official language standard, and ultimately to aid developers of Verilog-based tools; e.g., simulators, test generators, and verification...

    Provided By University of Illinois

  • White Papers // Jan 2012

    Optimizing Quality-of-Information in Cost-Sensitive Sensor Data Fusion

    This paper investigates maximizing quality of information subject to cost constraints in data fusion systems. The authors consider data fusion applications that try to estimate or predict some current or future state of a complex physical world. Examples include target tracking, path planning, and sensor node localization. Rather than optimizing...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Non-Blind Watermarking of Network Flows

    Linking network flows is an important problem in intrusion detection as well as anonymity. Passive traffic analysis can link flows but requires long periods of observation to reduce errors. Active traffic analysis, also known as flow watermarking, allows for better precision and is more scalable. Previous flow watermarks introduce significant...

    Provided By University of Illinois

  • White Papers // May 2012

    Exploiting Opportunistic Overhearing to Improve Performance of Mutual Exclusion in Wireless Ad Hoc Networks

    The authors design two mutual exclusion algorithms for wireless networks. Their mutual exclusion algorithms are distributed token based algorithms which exploit the opportunistic message overhearing in wireless networks. One of the algorithms is based on overhearing of token transmission. In the other algorithm, overhearing of both token and request messages...

    Provided By University of Illinois

  • White Papers // Nov 2011

    Experimental Performance Comparison of Byzantine Fault-Tolerant Protocols for Data Centers

    In this paper, the authors implement and evaluate three different Byzantine Fault-Tolerant (BFT) state machine replication protocols for data centers: BASIC: The classic solution from Pease, Shostak, and Lamport ; Digest: A simplified version of the seminal practical BFT protocol PBFT by Castro and Liskov ; and NCBA: a network...

    Provided By University of Illinois

  • White Papers // Dec 2011

    Capacity of Byzantine Consensus in Capacity Limited Point-to-Point Networks

    In this paper, the authors investigate the problem of maximizing the throughput, i.e., achieving capacity, of Byzantine consensus in point-to-point networks, in which each link has a capacity constraint. They derive an upper bound of the capacity of consensus in general point-to-point networks, and prove its tightness in 4-node complete...

    Provided By University of Illinois

  • White Papers // Oct 2008

    Wardrop Routing in Wireless Networks

    Routing protocols for multi-hop wireless networks have traditionally used shortest-path routing to obtain paths to destinations, and do not consider traffic load or delay as an explicit factor in the choice of routes. The authors focus on static mesh networks, and formally establish that if the number of sources is...

    Provided By University of Illinois

  • White Papers // Mar 2012

    Self-Partitioning Cloud Datastore for Scalable Transaction Processing Proposal

    The authors are designing a new cloud data storage system that will be highly scalable and yet still be able to provide strong data consistency guarantees. Their system extends existing cloud key/value stores with modular components for transaction management and access-based partitioning. They plan to utilize graph theory, clustering algorithms,...

    Provided By University of Illinois

  • White Papers // Jul 2011

    Multi-Core and Network Aware MPI Topology Functions

    MPI standard offers a set of topology-aware interfaces that can be used to construct graph and Cartesian topologies for MPI applications. These interfaces have been mostly used for topology construction and not for performance improvement. To optimize the performance, in this paper the authors use graph embedding and node/network architecture...

    Provided By University of Illinois

  • White Papers // Jan 2011

    Minimizing MPI Resource Contention in Multithreaded Multicore Environments

    With the ever-increasing numbers of cores per node in high-performance computing systems, a growing number of applications are using threads to exploit shared memory within a node and MPI across nodes. This hybrid programming model needs efficient support for multithreaded MPI communication. In this paper, the authors describe the optimization...

    Provided By University of Illinois

  • White Papers // Jun 2010

    PMI: A Scalable Parallel Process-Management Interface for Extreme-Scale Systems

    Parallel programming models on large-scale systems require a scalable system for managing the processes that make up the execution of a parallel program. The process-management system must be able to launch millions of processes quickly when starting a parallel program and must provide mechanisms for the processes to exchange the...

    Provided By University of Illinois

  • White Papers // Jun 2010

    Enabling Concurrent Multithreaded MPI Communication on Multicore Petascale Systems

    With the ever-increasing numbers of cores per node on HPC systems, applications are increasingly using threads to exploit the shared memory within a node, combined with MPI across nodes. Achieving high performance when a large number of concurrent threads make MPI calls is a challenging task for an MPI implementation....

    Provided By University of Illinois

  • White Papers // Aug 2009

    MPI on a Million Processors

    Petascale machines with close to a million processors will soon be available. Although MPI is the dominant programming model today, some researchers and users wonder (and perhaps even doubt) whether MPI will scale to such large processor counts. In this paper, the authors examine this issue of how scalable is...

    Provided By University of Illinois

  • White Papers // Aug 2010

    MPI at Exascale

    With petascale systems already available, researchers are devoting their attention to the issues needed to reach the next major level in performance, namely, exascale. Explicit message passing using the Message Passing Interface (MPI) is the most commonly used model for programming petascale systems today. In this paper, the authors investigate...

    Provided By University of Illinois

  • White Papers // Apr 2012

    An Architecture for Dynamic Service-Oriented Computing in Networked Embedded Systems

    Software development in real-time and embedded systems has traditionally focused on stand-alone applications with static models for scheduling and resource allocation. The authors' goal is to facilitate the development of embedded applications in an open system, where tasks and resources arrive and leave dynamically, and their execution is concurrent. They...

    Provided By University of Illinois

  • White Papers // Apr 2012

    Scoped Synchronization Constraints for Large Scale Actor Systems

    Very large scale systems of autonomous concurrent objects (Actors) require coordination models to meet two competing goals. On the one hand, the coordination models must allow Actors to dynamically modify protocols in order to adapt to requirement changes over the, likely extensive, lifetime of the system. On the other hand,...

    Provided By University of Illinois

  • White Papers // Dec 2009

    Scheduling Heterogeneous Real-Time Traffic Over Fading Wireless Channels

    The authors develop a general approach for designing scheduling policies for real-time traffic over wireless channels. They extend prior work, which characterizes a real-time flow by its traffic pattern, delay bound, timely-throughput requirement, and channel reliability, to allow time-varying channels, allow clients to have different deadlines, and allow for the...

    Provided By University of Illinois

  • White Papers // Feb 2010

    Dynamic Channel Reservation to Enhance Channel Access by Exploiting Structure of Vehicular Networks

    VANET protocols need to exploit the special structure of vehicular networks. This structure includes the one-dimensional nature of roads, the structure of lanes, the group mobility of vehicles, and the communication patterns of the envisaged applications. It is therefore of interest to examine how to specifically tailor VANET protocols to...

    Provided By University of Illinois

  • White Papers // Apr 2010

    Optimal Computation of Symmetric Boolean Functions in Tree Networks

    In this paper, the authors address the scenario where nodes with sensor data are connected in a tree network, and every node wants to compute a given symmetric Boolean function of the sensor data. They first consider the problem of computing a function of two nodes with integer measurements. They...

    Provided By University of Illinois

  • White Papers // May 2011

    Jellyfish: Networking Data Centers, Randomly

    Data centers today form the backbone of cloud operations. A well provisioned data center network is important to ensure that servers do not face bandwidth bottlenecks to utilization; to isolate services from each other; and to gain more freedom in workload placement, rather than having to tailor placement of workloads...

    Provided By University of Illinois

  • White Papers // Dec 2011

    Tiresias: Online Anomaly Detection for Hierarchical Operational Network Data

    Operational network data, management data such as customer care call logs and equipment system logs, is a very important source of information for network operators to detect problems in their networks. Unfortunately, there is lack of efficient tools to automatically track and detect anomalous events on operational data, causing ISP...

    Provided By University of Illinois

  • White Papers // Jul 2011

    Towards Practical Avoidance of Information Leakage in Enterprise Networks

    Preventing exfiltration of sensitive data is a central challenge facing many modern networking environments. In this paper, the authors propose a network-wide method of confining and controlling the flow of sensitive data within a network. Their approach is based on black-box differencing - they run two logical copies of the...

    Provided By University of Illinois

  • White Papers // Dec 2011

    Making DTNs Robust Against Spoofing Attacks With Localized Countermeasures

    In this paper, the authors propose countermeasures to mitigate damage caused by spoofing attacks in Delay-Tolerant Networks (DTNs). In their model, an attacker spoofs someone else's address (the victim's) to absorb packets from the network intended for that victim. Address spoofing is arguably a very severe attack in DTNs, compared...

    Provided By University of Illinois

  • White Papers // Nov 2011

    Lattice Codes for the Gaussian Relay Channel: Decode-and-Forward and Compress-and-Forward

    Lattice codes are known to achieve capacity in the Gaussian point-to-point channel, thereby achieving the same rates as random Gaussian codebooks. Lattice codes are also known to outperform random codes for certain channel models that are able to exploit their linearity. In this paper, the authors show that lattice codes...

    Provided By University of Illinois

  • White Papers // Jun 2011

    Achievable Rate Regions and Performance Comparison of Half Duplex Bi-Directional Relaying Protocols

    In a bi-directional relay channel, two nodes wish to exchange independent messages over a shared wireless half-duplex channel with the help of a relay. In this paper, the authors derive achievable rate regions for four new half-duplex protocols and compare these to four existing half-duplex protocols and outer bounds. In...

    Provided By University of Illinois

  • White Papers // Aug 2011

    A Lattice Compress-and-Forward Scheme

    Lattice codes have been shown to perform as well as random codes for certain Gaussian channels, and to outperform random codes for specific Gaussian channels. As much is known about lattice codes and their performance in single path (point-to-point, multiple access and broadcast where information flows along one path) source...

    Provided By University of Illinois

  • White Papers // Jun 2011

    Capacity to Within 3 Bits for a Class of Gaussian Interference Channels With a Cognitive Relay

    The Inter-Ference Channel with a Cognitive Relay (IFC-CR) consists of a classical two-user interference channel in which the two independent messages are also non-causally known at a cognitive relay node. In this paper a special class of IFC-CRs in which the sources do not create interference at the non-intended destinations...

    Provided By University of Illinois

  • White Papers // Jun 2011

    A New Capacity Result for the Z-Gaussian Cognitive Interference Channel

    This paper proposes a novel outer bound for the Gaussian cognitive interference channel in strong interference at the primary receiver based on the capacity of a multi-antenna broadcast channel with degraded message set. It then shows that for the Z-channel, i.e., when the secondary receiver experiences no interference and the...

    Provided By University of Illinois

  • White Papers // Jun 2011

    The Capacity of the Interference Channel With a Cognitive Relay in Strong Interference

    The interference channel with a cognitive relay consists of a classical interference channel with two source-destination pairs and with an additional cognitive relay that has a priori knowledge of the sources' messages and aids in the sources' transmission. The authors derive a new outer bound for this channel using an...

    Provided By University of Illinois

  • White Papers // Jun 2011

    Lattice Strategies for a Multi-Pair Bi-Directional Relay Network

    The authors consider a cellular network inspired channel model which consists of the bi-directional exchange of information between a base-station and M terminal nodes with the help of a relay. The base-station has a message for each of M terminals, and conversely, each terminal node has a message for the...

    Provided By University of Illinois

  • White Papers // Feb 2011

    An Outer Bound Region for the Parallel Two-Way Channel With Interference

    The classical interference channel models the communication limits of two independent, interfering streams of one-way data. In this paper, the authors extend the classical interference channel model to a new channel model in which two streams of two-way data interfere with each other. In the absence of interference, this model...

    Provided By University of Illinois

  • White Papers // Sep 2010

    List Decoding for Nested Lattices and Applications to Relay Channels

    The authors demonstrate a decoding scheme for nested lattice codes which is able to decode a list of a particular size which contains the transmitted codeword with high probability. This list decoder is analogous to that used in random coding arguments in achievability schemes of relay channels, and allows for...

    Provided By University of Illinois

  • White Papers // May 2009

    How I Learned to Stop Worrying and Love Plugins

    This position paper argues that browsers should be responsible for specifying and enforcing security policies for browser plugins. By enabling the browser to make security decisions on behalf of the plugin, browsers can significantly reduce the impact of plugin vulnerabilities and eliminate much of the risk posed by today's plugin...

    Provided By University of Illinois

  • White Papers // Jul 2011

    Online Advertisement, Optimization and Stochastic Networks

    In this paper, the authors propose a stochastic model to describe how search service providers charge client companies based on users' queries for the keywords related to these companies' ads by using certain advertisement assignment strategies. They formulate an optimization problem to maximize the long-term average revenue for the service...

    Provided By University of Illinois

  • White Papers // Sep 2011

    Holistic 3D Reconstruction of Urban Structures From Low-Rank Textures

    The authors introduce a new approach to reconstructing accurate camera geometry and 3D models for urban structures in a holistic fashion, i.e., without relying on extraction or matching of traditional local features such as points and edges. Instead, they use semi-global or global features based on transform invariant low-rank textures,...

    Provided By University of Illinois

  • White Papers // Feb 2011

    DustDoctor: A Self-Healing Sensor Data Collection System

    This paper presents a tool, called DustDoctor, for troubleshooting sensor data fusion systems where data are combined from multiple heterogeneous sources to compute actionable information. Application examples include target detection, critical infrastructure monitoring, and participatory sensing. In such systems, the correctness of end results may become compromised for a variety...

    Provided By University of Illinois

  • White Papers // Mar 2012

    OSA: An Optical Switching Architecture for Data Center Networks With Unprecedented Flexibility

    Data Center Networks (DCNs) form the backbone infrastructure of many large-scale enterprise applications as well as emerging cloud computing providers. This paper describes the design, implementation and evaluation of OSA, a novel optical switching architecture for DCNs. Leveraging runtime reconfigurable optical devices, OSA dynamically changes its topology and link capacities,...

    Provided By University of Illinois

  • White Papers // Jun 2011

    All-Optical Switching Data Center Network Supporting 100Gbps Upgrade and Mixed-Line-Rate Interoperability

    Over an 8-rack, 32-server WDM-based all-optical switching data center network, the authors show the network upgrade using single-wavelength or multi-wavelength 100 Gbps signals, and further show the mixed-line-rate interoperability between 100 Gbps and 10 Gbps signals. As one of the fast growing sectors in the internet applications, Data Center Networks...

    Provided By University of Illinois

  • White Papers // Jan 2012

    Service Composition for Advanced Multimedia Applications

    By composing distributed, autonomous services dynamically to provide new functionalities, service composition provides an attractive way for customized multimedia content production and delivery. Previous research work has addressed various aspects of service composition such as composibility, QoS-awareness, and load balancing. However, most of the work has focused on applications where...

    Provided By University of Illinois