University of Calgary

Displaying 1-40 of 498 results

  • White Papers // Nov 2014

    To Go or Not to Go: On Energy-aware and Communication-aware Robotic Operation

    The authors consider the scenario where a mobile robot needs to visit a number of Points Of Interest (POIs) in a workspace, gather their generated bits of information, and successfully transmit them to a remote station, while operating in a realistic communication environment, minimizing its total energy consumption (including both...

    Provided By University of Calgary

  • White Papers // May 2014

    Asymptotically Optimal Sequential Tests for Anomaly Detection: Switching with Memory

    Each anomalous process incurs a cost per unit time until its anomaly is identified and fixed. Different anomalous processes may incur different costs depending on their criticality to the system. Switching between processes and state declarations are allowed at all times, while decisions are based on all past observations and...

    Provided By University of Calgary

  • White Papers // May 2014

    Enhanced Lattice-Based Signatures on Reconfigurable Hardware

    The recent Bimodal LattIce Signature Scheme (BLISS) showed that lattice-based constructions have evolved to practical alternatives to RSA or ECC. Besides reasonably small signatures with 5600 bits for a 128-bit level of security, BLISS enables extremely fast signing and signature verification in software. However, due to the complex sampling of...

    Provided By University of Calgary

  • White Papers // May 2014

    A Sampling-Based Approach to Scalable Constraint Satisfaction in Linear Sampled-Data Systems - Part I: Computation

    Sampled-Data (SD) systems, which are composed of both discrete- and continuous-time components, are arguably one of the most common classes of cyber-physical systems in practice; most modern controllers are implemented on digital platforms while the plant dynamics that are being controlled evolve continuously in time. As with all cyber-physical systems,...

    Provided By University of Calgary

  • White Papers // May 2014

    Scalable Fault-Tolerant Data Feeds in AsterixDB

    In this paper, the authors describe the support for data feed ingestion in AsterixDB, an open-source Big Data Management System (BDMS) that provides a platform for storage and analysis of large volumes of semi-structured data. Data feeds are a mechanism for having continuous data arrive into a BDMS from external...

    Provided By University of Calgary

  • White Papers // May 2014

    ReDHiP: Recalibrating Deep Hierarchy Prediction for Energy Efficiency

    Recent hardware trends point to increasingly deeper cache hierarchies. In such hierarchies, accesses that lookup and miss in every cache involve significant energy consumption and degraded performance. To mitigate these problems, in this paper the authors propose Recalibrating Deep Hierarchy Prediction (ReDHiP), an architectural mechanism that predicts Last-Level Cache (LLC)...

    Provided By University of Calgary

  • White Papers // Apr 2014

    Multi-Level Coded Caching

    Recent work has demonstrated that for content caching, joint design of storage and delivery can yield significant benefits over conventional caching approaches. This is based on storing content in the caches, so as to create coded-multicast opportunities even amongst users with different demands. Such a coded-caching scheme has been shown...

    Provided By University of Calgary

  • White Papers // Apr 2014

    SELFISHMIGRATE: A Scalable Algorithm for Non-Clairvoyantly Scheduling Heterogeneous Processors

    Many computer architects believe that architectures consisting of heterogeneous processors will be the dominant architectural design in the future: simulation studies indicate that, for a given area and power budget, heterogeneous multiprocessors can offer an order of magnitude better performance for typical workloads. Looking at the consequences of Moore's Law...

    Provided By University of Calgary

  • White Papers // Mar 2014

    Lithography-Induced Limits to Scaling of Design Quality

    Quality and value of an IC product are functions of power, performance, area, cost and reliability. The forthcoming 2013 ITRS roadmap observes that while manufacturers continue to enable potential Moore's Law scaling of layout densities, the \"Realizable\" scaling in competitive products has for some years been significantly less. In this...

    Provided By University of Calgary

  • White Papers // Feb 2014

    The Melbourne Shuffle: Improving Oblivious Storage in the Cloud

    The authors present a simple, efficient, and secure data-oblivious randomized shuffle algorithm. This is the first secure data-oblivious shuffle that is not based on sorting. Their method can be used to improve previous oblivious storage solutions for network-based outsourcing of data. One of the unmistakable recent trends in networked computation...

    Provided By University of Calgary

  • White Papers // Feb 2014

    Optimal Reliability-Constrained Overdrive Frequency Selection In Multicore Systems

    In leading-edge process technologies, reliability is a first-class constraint for both IC design and system operation. For multicore systems, reliability affects task scheduling decisions since it constrains both performance and throughput. Previous works on reliability-constrained task scheduling have two basic limitations: either they cannot guarantee lifetime (e.g., that the chip...

    Provided By University of Calgary

  • White Papers // Jan 2014

    NOLO : A No-Loop, Predictive Useful Skew Methodology for Improved Timing in IC Implementation

    Useful skew is a well-known design technique that adjusts clock sink latencies to improve performance and/or robustness of high-performance IC designs. Current design methodologies apply useful skew after the netlist has been synthesized (e.g., with a uniform skew or clock uncertainty assumption on all flops), and after placement has been...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Timing Margin Recovery with Flexible Flip-Flop Timing Model

    In timing signoff for leading-edge SOCs, even few-picosecond timing violations will not only increase design turnaround time, but also degrade design quality (e.g., through power increase from insertion of extra buffers). Conventional flip-flop timing models have fixed values of setup/hold times and clock-to-q (c2q) delay, with some advanced \"Setup-Hold Pessimism...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Design Considerations for Solar Energy Harvesting Wireless Embedded Systems

    Sustainable operation of battery powered wireless embedded systems (such as sensor nodes) is a key challenge, and considerable research effort has been devoted to energy optimization of such systems. Environmental energy harvesting, in particular solar based, has emerged as a viable technique to supplement battery supplies. However, designing an efficient...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Ubiquitous Access to Distributed Data in Large-Scale Sensor Networks through Decentralized Erasure Codes

    Consider a large-scale wireless sensor network of n nodes, where a fraction k out of n generates data packets of global interest. Assuming that the individual nodes have limited storage and computational capabilities, the authors address the problem of how to enable ubiquitous access to the distributed data packets. Specially,...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Dynamic Information Flow Tracking on Multicores

    Dynamic Information Flow Tracking (DIFT) is a promising technique for detecting software attacks. Due to the computationally intensive nature of the technique, prior efficient implementations rely on specialized hardware support whose only purpose is to enable DIFT. Alternatively, prior software implementations are either too slow resulting in execution time increases...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Data Placement Based on the Seek Time Analysis of a MEMS-based Storage Device

    Reducing access times to secondary I/O devices has long been the focus of many systems researchers. With traditional disk drives, access time is the composition of transfer time, seek time and rotational latency, so many techniques as to minimize these factors, such as ordering I/O requests or intelligently placing data,...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Introduction to Hardware-Dependent Software Design

    Microelectronics is ubiquitous and took over large parts of the people daily life. Together with an increasing profileration of such embedded systems, their complexities are growing exponentially. Due to the rapidly increasing software content in embedded systems, Hardware-dependent Software (HdS) has become a critical topic in system design. In this...

    Provided By University of Calgary

  • White Papers // Jan 2014

    A Flexible, Syntax Independent Representation (SIR) for System Level Design Models

    System Level Design (SLD) is widely seen as a solution for bridging the gap between chip complexity and design productivity of Systems on Chip (SoC). SLD relieves the designer from detailed manual implementation by raising the level of abstraction in design models. There are many different modeling approaches to SLD....

    Provided By University of Calgary

  • White Papers // Jan 2014

    Creating Explicit Communication in SoC Models Using Interactive Re-Coding

    Communication exploration has become a critical step during SoC design. Researchers in the CAD community have proposed fast and efficient techniques for comprehensive design space exploration to expedite this critical design step. Although these advances have been helpful in reducing the design time significantly, the overall design time of the...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Group Key Agreement Efficient in Communication

    In recent years, group-oriented applications and protocols have been gaining popularity. Such applications typically involve communication over open networks where security is an important concern. Group key management is one of the basic building blocks in securing group communication. Most prior research in group key management focused on minimizing computation...

    Provided By University of Calgary

  • White Papers // Jan 2014

    On the Utility of Distributed Cryptography in P2P and MANETs: the Case of Membership Control

    Peer-to-peer systems enable efficient resource aggregation and are inherently scalable since they do not depend on any centralized authority. However, lack of a centralized authority, prompts many security-related challenges. Providing efficient security services in these systems is an active research topic which is receiving much attention in the security research...

    Provided By University of Calgary

  • White Papers // Jan 2014

    SRDP: Securing Route Discovery in DSR

    Routing is a critical function in multi-hop Mobile Ad-hoc NETworks (MANETs). A number of MANET-oriented routing protocols have been proposed, of which DSR is widely considered both the simplest and the most effective. At the same time, security in MANETs - especially, routing security - presents a number of new...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Impact of Attacks on a Secure Ad Hoc Routing Protocol: Performance Analysis and Countermeasures

    Mobile ad hoc networks have been an area of increasing research activity. Recently, a number of proto-cols have been proposed which secure ad hoc net-work routing; however, the evaluation of such protocols has been lacking. In particular, performance evaluations of such protocols have either been with-out an attacker, or under...

    Provided By University of Calgary

  • White Papers // Jan 2014

    RBWA: An Efficient Random-Bit Window-Based Authentication Protocol

    Given the wide and rapid deployment of \"Visitor networks\", how to authenticate the user and account the usage on the per-packet basis securely and yet efficiently is still a challenging problem. In this paper, the authors explore the tradeoff between performance and security, and propose a per-data-packet authentication and access...

    Provided By University of Calgary

  • White Papers // Jan 2014

    An Analysis Framework for Security in Web Applications

    Software systems interact with outside environments (e.g., by taking inputs from a user) and usually have particular assumptions about these environments. Unchecked or improperly checked assumptions can affect security and reliability of the systems. A major class of such problems is the improper validation of user inputs. In this paper,...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Security Issues in a Future Vehicular Network

    Both modern high-speed motorways and vehicles that drive upon them are becoming increasingly intelligent. In particular, communication devices are being installed in more and more cars and roadside infrastructure components. In this paper, the authors present a novel infrastructure for vehicular communication on highways and propose some potential applications aimed...

    Provided By University of Calgary

  • White Papers // Jan 2014

    A GALS Many-Core Heterogeneous DSP Platform with Source-Synchronous On-Chip Interconnection Network

    In this paper, the authors present a many-core heterogeneous computational platform that employs a GALS compatible circuit-switched on-chip network. The platform targets streaming DSP and embedded applications that have a high degree of task-level parallelism among computational kernels. The test chip was fabricated in 65nm CMOS consisting of 164 simple...

    Provided By University of Calgary

  • White Papers // Jan 2014

    High Throughput and Energy Efficient LDPC Decoders Using Multi-Split-Row Threshold Method

    Low Density Parity Check (LDPC) codes have received significant attention due to their superior error correction performance, and have been considered by emerging communication standards such as 10 Gigabit Ethernet (10GBASE-T), Digital Video Broadcasting (DVBS2), WiMAX (802.16e), Wi-Fi (802.11n) and WPANs (802.15.3c). Due to the codes' inherently irregular and global...

    Provided By University of Calgary

  • White Papers // Jan 2014

    On Computation and Resource Management in Networked Embedded Systems

    In this paper, the authors present the idea of managing the comprising computations of an application performed by an embedded networked system. An efficient algorithm for exploiting the timing slack of building blocks of the application is proposed. The slack of blocks can be utilized by replacing them with slower...

    Provided By University of Calgary

  • White Papers // Jan 2014

    A Low-Cost High-Speed Source-Synchronous Interconnection Technique for GALS Chip Multiprocessors

    The Globally Asynchronous Locally Synchronous (GALS) design style for a large area chip has become increasingly attractive due to the difficulty of designing global clocking circuits at high clock frequencies in the GHz range. In this paper, the authors present a high-speed interconnect network for a GALS multiprocessing system composed...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Modeling and Detecting Control Errors in Microprocessors

    Hardware verification has long been handicapped by the absence of good high-level design error models. To be useful for design validation, error models should satisfy three requirements: tests (simulation vectors) that cover the modeled errors should also provide very high coverage of actual design errors; the modeled errors should be...

    Provided By University of Calgary

  • White Papers // Jan 2014

    Power-Aware Register Renaming in High-Performance Processors Using Compiler Support

    Recently, energy consumption in embedded systems has become more and more important, mainly due to the fact that many systems are now being designed as mobile devices, i.e., they have to operate on battery power instead of using abundant power from wall sockets. One important aspect of such devices is...

    Provided By University of Calgary

  • White Papers // Dec 2013

    Bridging Automotive Systems, Safety and Software Engineering with a Seamless Toolchain

    Multi-core technologies strongly support functional integration, e.g. integration of different applications on the same control unit. However, these applications require different safety concepts with different levels of criticality; and providing consistency of the safety concept during the entire product lifecycle is a tedious task. The aim of this paper is...

    Provided By University of Calgary

  • White Papers // Nov 2013

    Asymptotically Efficient Lattice-Based Digital Signatures

    The authors present a general framework that converts certain types of linear collision-resistant hash functions into one-time signatures. Their generic construction can be instantiated based on both general and ideal (e.g. cyclic) lattices, and the resulting signature schemes are provably secure based on the worst-case hardness of approximating the shortest...

    Provided By University of Calgary

  • White Papers // Oct 2013

    Communication-Efficient MPC for General Adversary Structures

    A MultiParty Computation (MPC) protocol allows a set of players to compute a function of their inputs while keeping the inputs private and at the same time securing the correctness of the output. Most MPC protocols assume that the adversary can corrupt up to a fixed fraction of the number...

    Provided By University of Calgary

  • White Papers // Oct 2013

    Developing Systems for API Governance

    As scalable information technology evolves to a more cloud-like model, digital assets (code, data and software environments) that increasingly form the basis of research and education require curation as web-accessible services. \"Serviceizing\" digital assets consists of encapsulating assets in software that exposes them to web and mobile applications via well-defined,...

    Provided By University of Calgary

  • White Papers // Sep 2013

    Self-Consistency and Consistency-Based Detection and Diagnosis of Malicious Circuitry

    Hardware Trojans (HTs) have become a major concern in the modern IC industry, especially with the fast growth in IC outsourcing. HT detection and diagnosis are challenging due to the huge number of gates in modern IC designs and the high cost of testing. The authors propose a scalable and...

    Provided By University of Calgary

  • White Papers // Sep 2013

    Quantitative Intellectual Property Protection Using Physical-Level Characterization

    Hardware metering, the extraction of unique and persistent IDentifiers (IDs), is a crucial process for numerous Integrated Circuit (IC) intellectual property protection tasks, including protecting designs from unauthorized manufacturing. The currently known hardware metering approaches, however, are subject to alternations due to device aging, since they employ unstable manifestational IC...

    Provided By University of Calgary

  • White Papers // Aug 2013

    Graph Queries in a Next-Generation Datalog System

    The recent revival of interest in Datalog is driven by various developments that include the emergence of natural application areas, such as computer networking, parallel and distributed programming, and distributed data management, and the success of industrial-strength systems. Recent theoretical advances have enabled the use of special monotonic aggregates in...

    Provided By University of Calgary

  • White Papers // Aug 2012

    A Framework to Eliminate Backdoors From Response-Computable Authentication

    Response-Computable Authentication (RCA) is a two-party authentication model widely adopted by authentication systems, where an authentication system independently computes the expected user response and authenticates a user if the actual user response matches the expected value. Such authentication systems have long been threatened by malicious developers who can plant backdoors...

    Provided By University of Calgary

  • White Papers // Oct 2009

    Optimum Power Allocation Against Information Leakage in Wireless Network

    The authors investigate the problem of eavesdropping control in wireless communications networks. When a confidential message is transmitted through a wireless network, there is a potential security breach or 'Information leakage' due to the network's susceptibility to eavesdropping. In this paper, they quantify the information leakage problem in the context...

    Provided By University of Calgary

  • White Papers // Oct 2009

    A Theoretical Treatment of PA Power Optimization in Clipped MIMO-OFDM Systems

    In this paper, the authors present a theoretical framework for determining the optimal clipping level for a Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) system. They start by modeling of the clipping noise, and propose a Maximum Likelihood (ML) receiver for the resulting signal. The Bit Error...

    Provided By University of Calgary

  • White Papers // Nov 2010

    DMND: Collecting Data from Mobiles Using Named Data

    Technology advances in computations and wireless communications have made it economically feasible for manufacturers to collect data from vehicles on the road in order to monitor their operations and detect any potential problems. However to make this a reality requires a new architecture that can effectively handle vehicle mobility, intermittent...

    Provided By University of Calgary

  • White Papers // Jan 2012

    Data Naming in Vehicle-to-Vehicle Communications

    Vehicular networking is becoming reality. Today vehicles use TCP/IP to communicate with centralized servers through cellular networks. However many vehicular applications, such as information sharing for safety and real time traffic purposes, desire direct V2V communications which is difficult to achieve using the existing solutions. This paper explores the named-data...

    Provided By University of Calgary

  • White Papers // Nov 2012

    Cross-Layer Virtual Observers for Embedded Multiprocessor System-on-Chip (MPSoC)

    There is a growing concern about the increasing vulnerability of future computing systems to errors in the underlying hardware due to manufacturing process variability, exponentially increasing power dissipation and heating, as well as drastic and harsh environments such systems may have to operate in. This research proposes the concept of...

    Provided By University of Calgary

  • White Papers // Jan 2013

    Tie-Set Based Fault Tolerance for Autonomous Recovery of Double-Link Failures

    In this paper, the authors propose a mechanism for coping with double-link failures in an autonomous and distributed manner. They call it Tie-set Based Fault Tolerance (TBFT) because it utilizes tie-sets, which represent a set of the edges comprising a loop within the graph that represents the network. An autonomous...

    Provided By University of Calgary

  • White Papers // Aug 2012

    CrowdMAC: A Crowdsourcing System for Mobile Access

    Staggering growth levels in the number of mobile devices and amount of mobile Internet usage has caused network providers to move away from unlimited data plans to less flexible charging models. As a result, users are being required to pay more for short accesses or under-utilize a longer-term data plan....

    Provided By University of Calgary

  • White Papers // Jan 2013

    Improving Sensor Data Delivery During Disaster Scenarios With Resilient Overlay Networks

    In this paper, the authors consider many-to-one communication, in particular Internet-connected sensors and their relation to disaster response. They explore the application of resilient overlay networks to aid these devices, or individuals if they consider participatory sensing, in quickly and effectively routing around geographically correlated failures in the underlying network...

    Provided By University of Calgary

  • White Papers // Apr 2013

    Smart Communications Via a Tree-Based Overlay Over Multiple and Heterogeneous (TOMH) Spontaneous Networks

    The current networking scenario is characterized by widespread availability of ubiquitous devices with significant processing capabilities, e.g., Smartphones, tablets, and laptops. In addition, the simultaneous availability of multiple connectivity interfaces, e.g., cellular, WiFi, and Ethernet, pushes towards spontaneous networking scenarios where devices create a multi-network environment based on collaborative and...

    Provided By University of Calgary

  • White Papers // Oct 2012

    Exploiting an Elastic 2-Tiered Cloud Architecture for Rich Mobile Applications

    This dissertation exploits 2-Tier cloud architecture for rich mobile applications. It is based on the observation that using local resources in close proximity to the user, i.e. local clouds or cloudlets (in the second tier), can increase the quality and performance of mobile applications. In contrast, public cloud offerings (in...

    Provided By University of Calgary

  • White Papers // Jan 2013

    Compressive Link Acquisition in Multiuser Communications

    An important receiver operation is to detect the presence specific preamble signals with unknown delays in the presence of scattering, Doppler effects and carrier offsets. This task, referred to as "Link acquisition", is typically a sequential search over the transmitted signal space. Recently, many authors have suggested applying sparse recovery...

    Provided By University of Calgary

  • White Papers // Mar 2013

    Mobility-Assisted Energy-Aware User Contact Detection in Mobile Social Networks

    Many practical problems in mobile social networks such as routing, community detection, and social behavior analysis, rely on accurate user contact detection. The frequently used method for detecting user contact is through Bluetooth on Smartphones. However, Bluetooth scans consume lots of power. Although increasing the scan duty cycle can reduce...

    Provided By University of Calgary

  • White Papers // Mar 2013

    Inference-Driven Dynamic Access Scheme for Interference Management in Heterogeneous Networks

    Recent statistics have shown that more than 50% of voice calls and more than 70% of data traffic originate from indoor cellular subscribers. Yet, historically, substantial activities in wireless research and development have focused on high speed mobile users and the resulting fast fading channel problems. In fact, current cellular...

    Provided By University of Calgary

  • White Papers // Dec 2010

    Toward Region-And Action-Aware Second Life Clients: A Parameterized Second Life Traffic Model

    Virtual worlds, such as Second Life, are computer-simulated spaces divided into multiple regions, in which each user controls an avatar to perform actions (such as run and fly) in order to interact with other users. From a set of publicly available Second Life traces, the authors find that Second Life...

    Provided By University of Calgary

  • White Papers // Mar 2013

    Incentive Design for Heterogeneous User-Generated Content Networks

    In User-Generated Content (UGC) networks, users produce content and share it with other users with which they are connected over an (exogenously-determined) underlying topology. Such networks thrive if their users produce a sufficiently large amount of content. However, it is widely observed that self-interested users tend to lurk, i.e. only...

    Provided By University of Calgary

  • White Papers // May 2013

    Decentralizing Network Inference Problems with Multiple-Description Fusion Estimation (MDFE)

    Two forms of network inference (or tomography) problems have been studied rigorously: traffic matrix estimation or completion based on link-level traffic measurements, and link-level loss or delay inference based on end-to-end measurements. These problems are often posed as UnderDetermined Linear Inverse (UDLI) problems and solved in a centralized manner, where...

    Provided By University of Calgary

  • White Papers // Feb 2013

    Disaster-Resilient Virtual-Network Mapping and Adaptation in Optical Networks

    Today's Internet applications include grid- and cloud-computing services which can be implemented by mapping Virtual Networks (VNs) over physical infrastructure such as an optical network. VN mapping is a resource-allocation problem where fractions of the resources (e.g., bandwidth and processing) in the physical infrastructure (e.g., optical network and servers/data-centers) are...

    Provided By University of Calgary

  • White Papers // May 2013

    Local Privacy and Minimax Bounds: Sharp Rates for Probability Estimation

    The authors provide a detailed study of the estimation of probability distributions - discrete and continuous - in a stringent setting in which data is kept private even from the statistician. They give sharp minimax rates of convergence for estimation in these locally private settings, exhibiting fundamental tradeoffs between privacy...

    Provided By University of Calgary

  • White Papers // May 2011

    A Robust Trust Model for Named-Data Networks

    Any future Internet architecture must offer improved protection and resilience over today's network, which is subject to pervasive and persistent attacks. A recently emerging architecture, Named-Data Network (NDN), treats content as the primitive entity. This leads to decoupling location from identity, security and access, and retrieving content by name. NDN...

    Provided By University of Calgary

  • White Papers // Feb 2013

    Utility-Aware Deferred Load Balancing in the Cloud Driven by Dynamic Pricing of Electricity

    Distributed computing resources in a cloud computing environment provides an opportunity to reduce energy and its cost by shifting loads in response to dynamically varying availability of energy. This variation in electrical power availability is represented in its dynamically changing price that can be used to drive workload deferral against...

    Provided By University of Calgary

  • White Papers // Feb 2013

    Path Consolidation for Dynamic Right-Sizing of Data Center Networks

    Data center topologies typically consist of multi-rooted trees with many equal-cost paths between a given pair of hosts. Existing power optimization techniques do not utilize this property of data center networks for power proportionality. In this paper, the authors exploit this opportunity and show that significant energy savings can be...

    Provided By University of Calgary

  • White Papers // Dec 2012

    Securing Instrumented Environments over Content-Centric Networking: the Case of Lighting Control and NDN

    Instrumented environments, such as modern Building Automation Systems (BAS), are becoming commonplace and are increasingly interconnected with (and sometimes by) enterprise networks and the Internet. Regardless of the underlying communication platform, secure control of devices in such environments is a challenging task. The current trend is to move from proprietary...

    Provided By University of Calgary

  • White Papers // Feb 2011

    Space-Constrained Gram-Based Indexing for Efficient Approximate String Search

    Answering approximate queries on string collections is important in applications such as data cleaning, query relaxation, and spell checking, where inconsistencies and errors exist in user queries as well as data. Many existing algorithms use gram-based inverted-list indexing structures to answer approximate string queries. These indexing structures are "Notoriously" large...

    Provided By University of Calgary

  • White Papers // Jun 2012

    A New Worst-Case Throughput Bound for Oblivious Routing in Odd Radix Mesh Network

    Networks-on-Chip (NoC) has been proposed as a new intra-chip communication infrastructure. Regular topologies, especially the mesh topology, have been widely deployed. The choice of oblivious routing algorithm, which is oblivious of the network state when determining a route, has a significant impact on the network performance, such as the throughput...

    Provided By University of Calgary

  • White Papers // Mar 2013

    Interest Flooding Attack and Countermeasures in Named Data Networking

    Distributed Denial of Service (DDoS) attacks are an ongoing problem in today's Internet, where packets from a large number of compromised hosts thwart the paths to the victim site and/or overload the victim machines. In a newly proposed future Internet architecture, Named Data Networking (NDN), end users request desired data...

    Provided By University of Calgary

  • White Papers // Jan 2013

    NDN.JS: A JavaScript Client Library for Named Data Networking

    NDN.JS is the first JavaScript implementation of a client library for Named Data Networking (NDN). It facilitates NDN experimentation and usage by enabling end nodes to interact with an NDN network without installing the CCNx code package. It is also a first step towards exploring NDNbased Web architecture. NDN.JS is...

    Provided By University of Calgary

  • White Papers // May 2012

    Explaining BGP Slow Table Transfers

    Although there have been a plethora of studies on TCP performance in supporting of various applications, relatively little is known about the interaction between TCP and BGP, which is a specific application running on top of TCP. This paper investigates BGP's slow route propagation by analyzing packet traces collected from...

    Provided By University of Calgary

  • White Papers // Jan 2012

    A Comparative Study of Architectural Impact on BGP Next-Hop Diversity

    Large ISPs have been growing rapidly in both the size and global connectivity. To scale with the sheer number of routers, many providers have replaced the flat full-mesh iBGP connectivity with a hierarchical architecture, using either Route-Reflection (RR) or AS confederation. Given that each intermediate iBGP router in the hierarchy...

    Provided By University of Calgary

  • White Papers // Jan 2010

    Longitudinal Study of BGP Monitor Session Failures

    BGP routing data collected by RouteViews and RIPE RIS have become an essential asset to both the network research and operation communities. However, it has long been speculated that the BGP monitoring sessions between operational routers and the data collectors fail from time to time. Such session failures lead to...

    Provided By University of Calgary

  • White Papers // Aug 2011

    Design Implications for Enterprise Storage Systems Via Multi-Dimensional Trace Analysis

    Enterprise storage systems are facing enormous challenges due to increasing growth and heterogeneity of the data stored. Designing future storage systems requires comprehensive in-sights that existing trace analysis methods are ill-equipped to supply. In this paper, the authors seek to provide such insights by using a new methodology that leverages...

    Provided By University of Calgary

  • White Papers // Oct 2011

    Automating Application Deployment in Infrastructure Clouds

    Cloud computing systems are becoming an important platform for distributed applications in science and engineering. Infrastructure as a Service (IaaS) clouds provide the capability to provision Virtual Machines (VMs) on demand with a specific configuration of hardware resources, but they do not provide functionality for managing resources once they are...

    Provided By University of Calgary

  • White Papers // Sep 2012

    Cloud Platform Datastore Support

    There are many datastore systems to choose from that differ in many ways including public versus private cloud support, data management interfaces, programming languages, supported feature sets, fault tolerance, consistency guarantees, configuration, and their deployment processes. In this paper, the authors focus on technologies for structured data access (database/datastore systems)...

    Provided By University of Calgary

  • White Papers // Aug 2012

    A Pluggable Autoscaling Service for Open Cloud PaaS Systems

    In this paper, the authors present the design, implementation, and evaluation of a pluggable autoscaler within an open cloud Platform-as-a-Service (PaaS). They redefine High Availability (HA) as the dynamic use of virtual machines to keep services available to users, making it a subset of elasticity (the dynamic use of virtual...

    Provided By University of Calgary

  • White Papers // Dec 2009

    User Selection in Multiuser MIMO Systems With Secrecy Considerations

    This paper investigates simple user selection strategies in a multiuser downlink system with a single transmitter, multiple legitimate receivers, and a single eavesdropper, where all nodes are equipped with multiple antennas. No information regarding the eavesdropper is presumed at the transmitter, and the authors examine the MIMO downlink channel with...

    Provided By University of Calgary

  • White Papers // Aug 2010

    Wireless Relay Communications With Unmanned Aerial Vehicles: Performance and Optimization

    In this paper, the authors investigate a communication system in which Unmanned Aerial Vehicles (UAVs) are used as relays between ground-based terminals and a network base-station. They develop an algorithm for optimizing the performance of the ground-to-relay links through control of the UAV heading angle. To quantify link performance, they...

    Provided By University of Calgary

  • White Papers // Aug 2010

    Dynamic UAV Relay Positioning for the Ground-to-Air Uplink

    In this paper, the authors consider a collection of mobile single-antenna ground nodes communicating with a multi-antenna Unmanned Aerial Vehicle (UAV) on a multiple-access ground-to-air wireless communications link. The UAV uses beamforming to mitigate the inter-user interference and achieve Spatial Division Multiple Access (SDMA). In addition, the UAV dynamically adjusts...

    Provided By University of Calgary

  • White Papers // Nov 2010

    Closed-Loop Tracking Using Multimodal RF/EO Sensors

    This paper addresses the problem of using multiple, spatially distributed RF/EO sensors for target tracking. Data from the multi-modal sensors is collected at a fusion center, and used to track multiple objects in the sensors' field of view. Continuous approximations are made of the sensors' resolution in range, range rate...

    Provided By University of Calgary

  • White Papers // Nov 2010

    MIMO Interference Channel With Confidential Messages: Game Theoretic Beamforming Designs

    The authors study the achievable rate regions of the Multiple-Input Multiple-Output (MIMO) interference channel with confidential messages sent to two receivers. Under this model, each receiver is an eavesdropper for the other link and tries to decode both its own message and the message intended for the other receiver. They...

    Provided By University of Calgary

  • White Papers // Nov 2010

    Securing Multi-Antenna Two-Way Relay Channels With Analog Network Coding Against Eavesdroppers

    This paper investigates the vulnerability of Analog Network Coding (ANC) to physical layer attacks from adversarial users, when all nodes are equipped with multiple antennas. Specifically, the authors examine the MIMO Two Way Relay Channel (TWRC) with two users trying to communicate with each other via a relay node in...

    Provided By University of Calgary