University of Illinois

Displaying 1-40 of 216 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

    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 // 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 // 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

    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 // 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 // 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 // Sep 2005

    Classifying Crew Performance Failures in Commercial Aviation Accidents: Can We Get the Numbers Right?

    The purpose of accident investigation is to identify and organize a description of the process through which interacting elements and conditions result in an unfortunate event. Unfortunately, if accident investigators lack a cohesive definition of human factors issues, the investigation into human performance may be unsystematic, incomplete, or leave significant...

    Provided By University of Illinois

  • White Papers // May 2005

    Human Error and General Aviation Accidents: A Comprehensive, Fine-Grained Analysis Using HFACS

    The Human Factors Analysis and Classification System (HFACS) is a theoretically based tool for investigating and analyzing human error associated with accidents and incidents. Previous research performed at both at the University of Illinois and the Civil Aerospace Medical Institute (CAMI) have been highly successful and have shown that HFACS...

    Provided By University of Illinois

  • White Papers // Jan 2010

    Parallel Objects: Virtualization and In-Process Components

    Developing complex parallel applications that run efficiently on large parallel machines is dif-cult because the programmer has to handle many interrelated issues. Two issues that are of interest here are the specification of the parallel algorithm, and its efficient parallel implementation. Most current parallel programming models require the programmer to...

    Provided By University of Illinois

  • White Papers // Sep 2010

    Proteus: A Topology Malleable Data Center Network

    Full-bandwidth connectivity between all servers of a data center may be necessary for all-to-all traffic patterns, but such interconnects suffer from high cost, complexity, and energy consumption. Recent work has argued that if all-to-all traffic is uncommon, oversubscribed network architectures that can adapt the topology to meet traffic demands, are...

    Provided By University of Illinois

  • White Papers // Sep 2009

    Secure Unified Cellular Ad Hoc Network Routing

    Previous simulations have shown substantial performance gains can be achieved by using hybrid cellular and Wireless LAN (WLAN) approaches. In a hybrid system, a proxy in an area of strong connectivity (And therefore higher bandwidth) forwards traffic on behalf of a client in an area of weaker connectivity (And therefore...

    Provided By University of Illinois

  • White Papers // Jan 2010

    Interference-Aware Loop-Free Routing For Mesh Networks

    In recent years, there has been an explosive growth in the development of mesh networks to provide cheap yet high band width Internet access to areas that does not have coverage of high-bandwidth wired networks. Such mesh networks are composed of static wireless nodes. Each of these wireless nodes can...

    Provided By University of Illinois

  • White Papers // Jan 2010

    Efficient Metadata Management for Cloud Computing Applications

    Cloud computing applications require scalable, elastic and fault tolerant storage system. In this paper, the authors describe how metadata management can be improved for a file system built for large scale data-intensive applications. The authors implement Ring File System (RFS) that uses a single hop Distributed Hash Table, found in...

    Provided By University of Illinois

  • White Papers // Jan 2010

    Log Correlation for Intrusion Detection: A Proof of Concept

    Intrusion detection is an important part of networked systems security protection. Although commercial products exist, finding intrusions has proven to be a difficult task with limitations under current techniques. Therefore, improved techniques are needed. The authors argue the need for correlating data among different logs to improve intrusion detection systems...

    Provided By University of Illinois

  • White Papers // Jan 2010

    An Architecture for Regulatory Compliant Database Management

    Spurred by financial scandals and privacy concerns, governments worldwide have moved to ensure confidence in digital records by regulating their retention and deletion. These requirements have led to a huge market for compliance storage servers, which ensure that data are not shredded or altered before the end of their mandatory...

    Provided By University of Illinois

  • White Papers // Sep 2009

    OCast: Optimal Multicast Routing Protocol for Wireless Sensor Networks

    In this paper, authors describe oCast, an energy-optimal multicast routing protocol for wireless sensor networks. The general minimum-energy multicast problem is NP-hard. Intermittent connectivity that results from duty-cycling further complicates the problem. Nevertheless, authors present both a centralized and distributed algorithm that are provably optimal when the number of destinations...

    Provided By University of Illinois

  • White Papers // Jan 2010

    An XML-Based Quality of Service Enabling Language for the Web

    In this paper, the authors introduce an XML-based Hierarchical QoS Markup Language, called HQML, to enhance distributed multimedia applications on the World Wide Web (WWW) with Quality of Service (QoS) capability. The design of HQML is based on two observations: the absence of a systematic QoS specification language, that can...

    Provided By University of Illinois

  • White Papers // Jan 2011

    On the Use of Compilers in DSP Laboratory Instruction

    A modern DSP laboratory course should teach students how to quickly develop efficient applications using a mixture of C and assembly instructions. Since typical irregular DSP microprocessor architectures present some challenges to traditional optimizing compilers, the authors introduced a novel new interactive optimizing compiler, VISTA, in a DSP laboratory course...

    Provided By University of Illinois

  • White Papers // Jan 2011

    Bypass Routing: An On-Demand Local Recovery Protocol for Ad Hoc Networks

    On-demand routing protocols for ad hoc networks reduce the cost of routing in high mobility environments. However, route discovery in on-demand routing is typically performed via network-wide flooding, which consumes a substantial amount of bandwidth. In this paper, the authors present bypass routing, a local recovery protocol that aims to...

    Provided By University of Illinois

  • White Papers // May 2010

    Overcoming an Untrusted Computing Base: Detecting and Removing Malicious Hardware Automatically

    The computer systems security arms race between attackers and defenders has largely taken place in the domain of software systems, but as hardware complexity and design processes have evolved, novel and potent hardware-based security threats are now possible. This paper presents a hybrid hardware/software approach to defending against malicious hardware....

    Provided By University of Illinois

  • White Papers // Aug 2009

    A Static-Hybrid Approach for Providing Low Delay Routing for Real Time Applications

    Multichannel, multihop wireless networks can improve system performance by allowing more simultaneous transmissions in the network than when compared to a single channel network. This in turn results in a higher network throughput and improved spectral efficiency. In order to maintain connectivity across nodes that operate on different channels, most...

    Provided By University of Illinois

  • White Papers // Sep 2009

    Adjacent Channel Interference Reduction in Multichannel Wireless Networks Using Intelligent Channel Allocation

    The performance of a multichannel, multi-radio wireless network is often limited by interference due to concurrent transmissions on the same and adjacent channels. These interference effects may be either due to simultaneous traffic activity by the multiple radios within a node or due to transmission by neighboring nodes. In this...

    Provided By University of Illinois

  • White Papers // Dec 2010

    WiSP: A Protocol for Overcoming MAC Overheads Using Packet Size Dependent Channel Widths

    In this paper, the authors propose to reduce the effect of rate-independent MAC overheads in random access protocols by partitioning the transmission channel spectrum into a narrow channel and a wide channel. The narrow channel is used for transmitting the short packets (approximately 100 bytes long) and the wide channel...

    Provided By University of Illinois

  • White Papers // Jan 2011

    Capacity of Byzantine Agreement With Finite Link Capacity

    The authors consider the problem of maximizing the throughput of Byzantine agreement, when communication links have finite capacity. Byzantine agreement is a classical problem in distributed computing. In existing literature, the communication links are implicitly assumed to have infinite capacity. The problem changes significantly when the capacity of links is...

    Provided By University of Illinois

  • White Papers // Apr 2010

    Capacity of Byzantine Agreement: Complete Characterization of Four-Node Networks

    In this paper, the authors consider the problem of maximizing the throughput of Byzantine agreement. Byzantine agreement is a classical problem in distributed computing, with initial solutions presented in the seminal work of Pease, Shostak and Lamport. Many variations on the Byzantine agreement problem have been introduced in the past,...

    Provided By University of Illinois

  • White Papers // Mar 2010

    Selfish Misbehavior in the Optimal Cross-Layered Rate Control of Wireless Networks

    The authors consider the problem of selfish misbehavior in the optimal cross-layered rate control mechanism of wireless networks. Rate control algorithms of wireless networks are designed under the assumption that network hosts will follow the algorithm specifications. In this paper, they explain a scenario in which a selfish user achieves...

    Provided By University of Illinois

  • White Papers // Mar 2010

    A Distributed Throughput-Optimal CSMA/CA

    This paper addresses a distributed throughput-optimal CSMA/CA for wireless ad hoc networks, which is called the preemptive CSMA/CA. It achieves the optimality in a completely distributed fashion, even with discrete backoff time, non-zero carrier sense delay and data packet collisions. The algorithm is derived from the extension of Q-CSMA by...

    Provided By University of Illinois

  • White Papers // Mar 2010

    SHORT: A Static-Hybrid Approach for Routing Real Time Applications Over Multichannel, Multihop Wireless Networks

    Many of the existing multichannel wireless network implementations rely on channel switching capability of the wireless radios to ensure network connectivity. However, due to both software and hardware restrictions switching channels incur a significant delay, which can be prohibitive for many delay sensitive, real time applications, such as VoIP and...

    Provided By University of Illinois

  • White Papers // Jan 2010

    On Providing Non-Uniform Scheduling Guarantees in a Wireless Network

    Significant research effort has been directed towards the design and performance analysis of imperfect scheduling policies for wireless networks. These imperfect schedulers are of interest despite being sub-optimal, as they allow for more tractable implementation at the expense of some loss in performance. However much of this prior work takes...

    Provided By University of Illinois

  • White Papers // Oct 2009

    Scheduling in Multi-Channel Wireless Networks

    The availability of multiple orthogonal channels in a wireless network can lead to substantial performance improvement by alleviating contention and interference. However, this also gives rise to non-trivial channel coordination issues. The situation is exacerbated by variability in the achievable data-rates across channels and links. Thus, scheduling in such networks...

    Provided By University of Illinois

  • White Papers // Nov 2010

    Efficient Access Algorithms for Dynamic Many-Tag Passive RFID Storage Systems

    In this paper, the authors investigate efficient algorithms for accessing information stored in a large number of RFID tags. Interrogators, equipped with RFID scanners, regularly arrive at the tag system, read from and write messages to the tags, and then leave. They develop techniques for the interrogators to read the...

    Provided By University of Illinois

  • White Papers // Nov 2010

    Overcoming MAC Overheads Using Packet Size Dependent Channel Widths

    In this paper, the authors propose to reduce the MAC overheads in random access protocols by partitioning the channel spectrum used into a narrow channel and a wide channel. The narrow channel is used for transmitting the short packets (approximately 100 bytes long) and the wide channel is used for...

    Provided By University of Illinois

  • White Papers // Nov 2010

    A Channel Assignment Algorithm for Opportunistic Routing in Multichannel, Multi-Radio Wireless Mesh Networks

    Opportunistic routing emerged as a novel technique to cope with the problem of highly unpredictable and lossy wireless channels in urban wireless mesh networks. However, existing opportunistic routing protocols only consider single-radio wireless nodes, and assume that all the nodes work on the same channel, without exploiting possible concurrent transmissions...

    Provided By University of Illinois

  • White Papers // Oct 2009

    Experiences Validating the Access Policy Tool in Industrial Settings

    The Access Policy Tool (APT) analyzes the firewall configuration in an enterprise network for compliance with global access policy, e.g., such as describes the industry's best practices. APT is the culmination of several years of academic research and development; in this last year the authors have been working with industrial...

    Provided By University of Illinois

  • White Papers // Oct 2009

    Complexity Bounds for the Verification of Real-Time Software

    The authors present uniform approaches to establish complexity bounds for decision problems such as reachability and simulation, which arise naturally in the verification of timed software systems. The authors model timed software systems as timed automata augmented with a data store (like a pushdown stack) and show that there is...

    Provided By University of Illinois

  • White Papers // Jan 2011

    A Vehicle-to-Vehicle Communication Protocol for Cooperative Collision Warning

    This paper proposes a vehicle-to-vehicle communication protocol for cooperative collision warning. Emerging wireless technologies for Vehicle-To-Vehicle (V2V) and Vehicle-To-Roadside (V2R) communications such as DSRC are promising to dramatically reduce the number of fatal roadway accidents by providing early warnings. One major technical challenge addressed in this paper is to achieve...

    Provided By University of Illinois

  • White Papers // Dec 2009

    MIS: Malicious Nodes Identification Scheme in Network-Coding-Based Peer-to-Peer Streaming

    Network coding has been shown to be capable of greatly improving quality of service in P2P live streaming systems (e.g., IPTV). However, network coding is vulnerable to pollution attacks where malicious nodes inject into the network bogus data blocks that are combined with other legitimate blocks at downstream nodes, leading...

    Provided By University of Illinois

  • White Papers // Sep 2010

    Tiered Incentives for Integrity Based Queuing

    The authors propose a tiered incentive system called Integrity-Based Queuing (IBQ) for protection against Internet Distributed Denial-of-Service (DDoS) attacks. The authors' proposal can be implemented step-by-step where each integrity improvement brings a direct benefit to the autonomous system making it. IBQ proposes preferential queuing based on integrity: good, bad and...

    Provided By University of Illinois

  • White Papers // Nov 2010

    Modified Version of De Jong Radiopropagation Model

    a semi deterministic propagation model based on De Jong recommendations is described. It is an extended 2D-ray tracing model for planning microcell in urban environment. It uses virtual sources, in order to model the Wave Propagation phenomena (building transmissions, tree scattering, diffraction by external corners, and wall reflections) of a...

    Provided By University of Illinois

  • White Papers // Jan 2011

    Achieving Delay Guarantees in Ad Hoc Networks by Adapting IEEE 802.11 Contention Windows

    In this paper, the authors propose a new protocol, named DDA (Distributed Delay Allocation), which provides average delay guarantees to real-time multimedia applications in wireless ad hoc networks. By adapting the contention window sizes of IEEE 802.11, DDA schedules packets of flows according to their individual delay requirements. The novelty...

    Provided By University of Illinois

  • White Papers // Jun 2010

    An Empirical Study of Reported Bugs in Server Software With Implications for Automated Bug Diagnosis

    Reproducing bug symptoms is a prerequisite for performing automatic bug diagnosis. Do bugs have characteristics that ease or hinder automatic bug diagnosis? In this paper, the authors conduct a thorough empirical study of several key characteristics of bugs that affect reproducibility at the production site. They examine randomly selected bug...

    Provided By University of Illinois

  • White Papers // Jan 2011

    Integrating Dynamic Power Management in Systems With Multiple DVS Components

    Recent embedded computing platforms offer multiple independent clocks for different components involved in processing a single instruction stream, such as CPU and memory, giving rise to a new category of power management policies, called MultiDVS, where the different components can be clocked down to different degrees, independently. This paper presents...

    Provided By University of Illinois

  • White Papers // Jan 2011

    A Cross-Layer Routing and Congestion Control for Distributed Systems

    Distributed systems have been widely deployed and used in different fields. The Internet itself with all the challenges it brings is one of the successful distributed systems. There has been a lot of research in the efficient design, implementation and evaluation of distributed systems. One of the research challenges in...

    Provided By University of Illinois

  • White Papers // Oct 2010

    Resource Inflation Threats to Denial of Service Countermeasures

    Currency-based mechanisms have been proposed as a way to use resource fairness among contenders for a service to thwart Denial of Service (DoS) attacks. Under resource fairness, a server allocates its service to the clients in proportion to their payment of a resource, making the resource serve as a kind...

    Provided By University of Illinois

  • White Papers // Nov 2010

    Social Network-Aware Disk Management

    Disk access patterns of social networking applications are different from those of traditional applications. However, today's disk layout techniques are not adapted to social networking workloads and thus suffer in performance. In this paper, the authors first present disk layout techniques that leverage community structure in the social graph to...

    Provided By University of Illinois

  • White Papers // Dec 2010

    Dynamic Mapping of an as Network Into a Smaller Network of Border Routers

    In this paper the authors present a cross layer routing and congestion control scheme which can map an enterprise network into a smaller network of boarder routers. One of the boarder routers in the scheme called a main node computes the virtual link (tunnel) capacities and corresponding queue size for...

    Provided By University of Illinois