University of Waterloo

Displaying 1-40 of 181 results

  • White Papers // Aug 2012

    A Framework for Ubiquitous IP Communications in Vehicle to Grid Networks

    The electrical grid is a critical infrastructure that is slowly moving towards a more reliable and efficient supply system: the Smart Grid. As part of this migration process, a new group of energy-aware and emission-free technologies are being developed. Electric vehicles are a promising technology that belongs to that group....

    Provided By University of Waterloo

  • White Papers // Aug 2012

    Decentralized Inverter Control in Microgrids Based on Power Sharing Information Through Wireless Communications

    For the future smart grid, decentralized inverter control is essential in Distributed Generation (DG) micro-grids where a powerful central controller is unavailable for cost and reliability concerns. However, decentralized inverter control suffers from limited system stability mainly because of the lack of communications among different inverters. In this paper, the...

    Provided By University of Waterloo

  • White Papers // Jun 2012

    Enable Pervasive Healthcare Through Continuous Remote Health Monitoring

    In this paper, the authors introduce a novel Remote Health Monitoring (RHM) system to enable high-quality pervasive healthcare services to users with low delivery delay and reduced costs. They define the RHM architecture and summarize the design considerations. They then present a promising commercialized solution, ViiCare, with system infrastructures and...

    Provided By University of Waterloo

  • White Papers // Apr 2012

    Implementing Pairings at the 192-Bit Security Level

    The authors implement asymmetric pairings derived from Kachisa-Schaefer-Scott (KSS), Barreto-Naehrig (BN), and Barreto-Lynn-Scott (BLS) elliptic curves at the 192-bit security level. Somewhat surprisingly, they find pairings derived from BLS curves with embedding degree 12 to be the fastest for their serial as well as their parallel implementations. The serial implementations...

    Provided By University of Waterloo

  • White Papers // Apr 2012

    FIFO Queueing Policies for Packets With Heterogeneous Processing

    The authors consider the problem of managing a bounded size First-In-First-Out (FIFO) queue buffer, where each incoming unit-sized packet requires several rounds of processing before it can be transmitted out. Their objective is to maximize the total number of successfully transmitted packets. They consider both push-out (when the policy is...

    Provided By University of Waterloo

  • White Papers // Mar 2012

    Cross-Band Interference Reduction Trade-Offs in SISO and MISO OFDM-Based Cognitive Radios

    Cognitive radio is a promising approach for efficient utilization of radio spectrum. Due to its high spectral efficiency and flexibility, OFDM is considered as a good signaling scheme for cognitive radios. In this paper, the authors investigate the problem of cross-band interference minimization in OFDM-based cognitive systems. Cross-band interference is...

    Provided By University of Waterloo

  • White Papers // Mar 2012

    Multiagent Coordination in Microgrids Via Wireless Networks

    The future smart grid is expected to be an integration of intelligent microgrids featured by localized electricity generation, storage, and consumption. Wireless communication is a promising means to facilitate pervasive microgrid monitoring and control at a high flexibility and low deployment cost. In order to avoid a single point of...

    Provided By University of Waterloo

  • White Papers // Mar 2012

    SUCCESS: A Secure User-Centric and Social-Aware Reputation Based Incentive Scheme for DTNs

    Delay/Disruption Tolerant Networks (DTNs) are self-organized wireless ad-hoc networks, where end-to-end connectivity can not be guaranteed and communications rely on the assumption that the nodes are willing to store-carry-and-forward bundles in an opportunistic way. However, this assumption would be easily violated due to the selfish nodes which are unwilling to...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    Optimally Robust Private Information Retrieval

    The authors give a protocol for multi-server information-theoretic private information retrieval which achieves the theoretical limit for Byzantine robustness. That is, the protocol can allow a client to successfully complete queries and identify server misbehavior in the presence of the maximum possible number of malicious servers. They have implemented their...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    Multidimensional Meet-in-the-Middle Attack and Its Applications to GOST, KTANTAN and Hummingbird-2

    This paper investigates a new approach to analyze symmetric ciphers by dividing the algorithms to consecutive sub-ciphers and then evaluating them separately. This attack is suitable for ciphers with simple key schedules and having block sizes smaller than key lengths. The authors have successfully applied this multidimensional approach to the...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    A Secure Payment Scheme With Low Communication and Processing Overhead for Multihop Wireless Networks

    The authors propose RACE, a report-based payment scheme for multi-hop wireless networks to stimulate node cooperation, regulate packet transmission, and enforce fairness. The nodes submit lightweight payment reports (instead of receipts) to the Accounting Center (AC) and temporarily store undeniable security tokens called Evidences. The reports contain the alleged charges...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    Enabling Pervasive Healthcare With Privacy Preservation in Smart Community

    Smart community is an emerging Internet of Things application. It supports a variety of high-value automated services such as pervasive healthcare through a multi-hop community network of smart homes in a local residential region. In this paper, the authors study privacy preserving data communication between patients and an online healthcare...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    PReFilter: An Efficient Privacy-Preserving Relay Filtering Scheme for Delay Tolerant Networks

    Without direct path, information delivery in sparse Delay Tolerant Networks (DTNs) typically relies on intermittent relays, making the transmission not only unreliable but also time consuming. To make the matter even worse, the source nodes may transmit some encrypted "Junk" information, similar as the spam emails in current mail systems,...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Exploiting Prediction to Enable Secure and Reliable Routing in Wireless Body Area Networks

    In this paper, the authors propose a distributed Prediction-based Secure and Reliable routing framework (PSR) for emerging Wireless Body Area Networks (WBANs). It can be integrated with a specific routing protocol to improve the latter's reliability and prevent data injection attacks during data communication. In PSR, using past link quality...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Location Privacy Preservation in Collaborative Spectrum Sensing

    Collaborative spectrum sensing has been regarded as a promising approach to enable secondary users to detect primary users by exploiting spatial diversity. In this paper, the authors consider a converse question: could space diversity be exploited by a malicious entity, e.g., an external attacker or an untrusted Fusion Center (FC),...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Cost-Effective Barrier Coverage by Mobile Sensor Networks

    Barrier coverage problem in emerging mobile sensor networks has been an interesting research issue. Existing solutions to this problem aim to decide one-time movement for individual sensors to construct as many barriers as possible, which may not work well when there are no sufficient sensors to form a single barrier....

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Cooperative Cognitive Radio Networking Using Quadrature Signaling

    A quadrature signaling based two-phase cooperation framework for cooperative cognitive radio networking is proposed. By leveraging the degrees of freedom provided by orthogonal modulation, secondary users are able to relay the traffic of primary users and transmit their own in the same time slot without interference. To evaluate the cooperation...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Intermodeling, Queries, and Kleisli Categories

    Specification and maintenance of relationships between models are vital for MDE. The authors show that a wide class of such relationships can be specified in a compact and precise manner, if inter-model mappings are allowed to link derived model elements computed by corresponding queries. Composition of such mappings is not...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    On the Limitations of the Naive Lattice Decoding

    In this paper, the inherent drawbacks of the naive lattice decoding for MIMO fading systems is investigated. The authors show that using the naive lattice decoding for MIMO systems has considerable deficiencies in terms of the rate-diversity trade-off. Unlike the case of maximum-likelihood decoding, in this case, even the perfect...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Communication Over MIMO Broadcast Channels Using Lattice-Basis Reduction

    A new viewpoint for adopting the lattice reduction in communication over MIMO broadcast channels is introduced. Lattice basis reduction helps one to reduce the average transmitted energy by modifying the region which includes the constellation points. Also, the outage probability for both cases of fixed-rate users and fixed sum-rate is...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    LLL Reduction Achieves the Receive Diversity in MIMO Decoding

    Diversity order is an important measure for the performance of communication systems over MIMO fading channels. In this paper, the authors prove that in MIMO multiple access systems (or MIMO point-to-point systems with V-BLAST transmission), lattice-reduction-aided decoding achieves the maximum receive diversity (which is equal to the number of receive...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Soft Reconstruction of Speech in the Presence of Noise and Packet Loss

    Exploiting the residual redundancy in a source coder output stream during the decoding process has been proven to be a bandwidth efficient way to combat the noisy channel degradations. In this paper, the authors consider soft reconstruction of speech spectrum, in GSM Adaptive Multi-Rate and IS-641 vocoders, transmitted over a...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Spectral-Efficient Differential Space-Time Coding Using Non-Full-Diverse Constellations

    In this paper, a method is proposed to construct spectral-efficient unitary space-time codes for high-rate differential communications over multiple-antenna channels. Unlike most of the known methods which are designed to maximize the diversity product (the minimum determinant distance), the authors' objective is to increase the spectral efficiency. The simulation results...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    CommitCoin: Carbon Dating Commitments With Bitcoin

    In the standard definition of a commitment scheme, the sender commits to a message and immediately sends the commitment to the recipient interested in it. However, the sender may not always know at the time of commitment who will become interested in verifying it. Further, when the interested party does...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Extended Combinatorial Constructions for Peer-to-Peer User-Private Information Retrieval

    The authors consider User-Private Information Retrieval (UPIR), an interesting alternative to Private Information Retrieval (PIR) introduced by Domingo-Ferrer et al.. In UPIR, the database knows which records have been retrieved, but does not know the identity of the person making the query. The goal of UPIR, then, is to disguise...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Efficient Algorithms to Solve a Class of Resource Allocation Problems in Large Wireless Networks

    The authors focus on efficient algorithms for resource allocation problems in large wireless networks. They first investigate the link scheduling problem and identify the properties that make it possible to compute solutions efficiently. They, then show that the node on-off scheduling problem shares these features and is amenable to the...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Throughput-Lifetime Tradeoffs in Multihop Wireless Networks Under a Realistic Interference Model

    Throughput and lifetime are both crucial design objectives for multi-hop wireless networks. In general, it is not sufficient to optimize either of them separately. As these two objectives are often conflicting with each other, the authors can only hope to identify the tradeoffs between them. This entails a harder problem...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    TESP2: Timed Efficient Source Privacy Preservation Scheme for Wireless Sensor Networks

    Recent advances in micro electro mechanical systems and wireless communication have paved the way for the rapid deployment of wireless sensor networks, which have been well recognized as a ubiquitous and general approach for some emerging applications such as real-time traffic monitoring, ecosystem and battlefield surveillance. Typically, a wireless sensor...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Re-Encryption-Based Key Management Towards Secure and Scalable Mobile Applications in Clouds

    Cloud computing confers strong economic advantages, but many clients are reluctant to implicitly trust a third-party cloud provider. To address these security concerns, data may be transmitted and stored in encrypted form. Major challenges exist concerning the aspects of the generation, distribution, and usage of encryption keys in cloud systems,...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Faster Facility Location and Hierarchical Clustering

    The authors propose several methods to speed up the facility location, and the single link and the complete link clustering algorithms. The local search algorithm for the facility location is accelerated by introducing several space partitioning methods and a parallelisation on the CPU of a standard desktop computer. The influence...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Efficient On-Demand Data Service Delivery to High-Speed Trains in Cellular/Infostation Integrated Networks

    In this paper, the authors investigate on-demand data services for high-speed trains via a cellular/infostation integrated network. Service requests and acknowledgements are sent through the cellular network to a content server, while data delivery is achieved via trackside infostations. The optimal resource allocation problem is formulated by taking account of...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Multipath Transmission for Wireless Internet Access - From an End-to-End Transport Layer Perspective

    With the growing demand of Internet services, network operators have put significant efforts to improve network error resilience and efficiency. Since there exist different wired/wireless technologies for Internet access such as Digital Subscriber Line (DSL), Ethernet, and worldwide interoperability for microwave access (WiMax), a mobile host can use multiple access...

    Provided By University of Waterloo

  • White Papers // Nov 2011

    Network Cooperation for Energy Saving in Green Radio Communications

    Financial and environmental considerations have motivated a trend in wireless communication network design and operation to minimize the amount of energy consumption. Such a trend is referred to as green radio communications. In this paper, network cooperation is investigated as a means of energy saving. Networks with overlapped coverage can...

    Provided By University of Waterloo

  • White Papers // Nov 2011

    A Cloud-Based Scheme for Protecting Source-Location Privacy Against Hotspot-Locating Attack in Wireless Sensor Networks

    In wireless sensor networks, adversaries can make use of traffic information to locate the monitored objects, e.g., to hunt endangered animals or kill soldiers. In this paper, the authors first define a hotspot phenomenon that causes an obvious inconsistency in the network traffic pattern due to a large volume of...

    Provided By University of Waterloo

  • White Papers // Oct 2011

    Self Adaptive Contention Aware Routing Protocol for Intermittently Connected Mobile Networks

    This paper introduces a novel multi-copy routing protocol, called Self Adaptive Utility-based Routing Protocol (SAURP), for Delay Tolerant Networks (DTNs) that are possibly composed of a vast number of devices in miniature such as smart phones of heterogeneous capacities in terms of energy resources and buffer spaces. SAURP is characterized...

    Provided By University of Waterloo

  • White Papers // Oct 2011

    Network-Wide Local Unambiguous Failure Localization (NWL-UFL) Via Monitoring Trails

    Monitoring trail (m-trail) has been proposed as an effective approach for link failure localization in all-optical WDM (Wavelength Division Multiplexing) mesh networks. Previous studies in failure localization rely on alarm dissemination via control plane signaling such that the network controller can collect the flooded alarms to form an alarm code...

    Provided By University of Waterloo

  • White Papers // Oct 2011

    Generating Range Fixes for Software Configuration

    To prevent configuration errors, highly configurable software often allows defining constraints over the available options. As these constraints can be complex, fixing a configuration that violates one or more constraints can be challenging. Although several fix-generation approaches exist, their applicability is limited because they typically generate only one fix, failing...

    Provided By University of Waterloo

  • White Papers // Sep 2011

    Model Synchronization, Mappings, Tile Algebra, and Categories

    The paper presents a novel algebraic framework for specification and design of model synchronization tools. The basic premise is that synchronization procedures, and hence algebraic operations modeling them, are diagrammatic: they take a configuration (diagram) of models and mappings as their input and produce a diagram as the output. Many...

    Provided By University of Waterloo

  • White Papers // Sep 2011

    Characterizing Task Usage Shapes in Google~s Compute Clusters

    The increase in scale and complexity of large compute clusters motivates a need for representative workload bench-marks to evaluate the performance impact of system changes, so as to assist in designing better scheduling algorithms and in carrying out management activities. To achieve this goal, it is necessary to construct workload...

    Provided By University of Waterloo

  • White Papers // Sep 2011

    Resolving State Inconsistency in Distributed Fault-Tolerant Real-Time Dynamic TDMA Architectures

    State consistency in safety-critical distributed systems is mandatory for synchronizing distributed decisions as found in dynamic Time Division Multiple Access (TDMA) schedules in the presence of faults. A TDMA schedule that supports networked systems making decisions at run time is sensitive to transient faults, because stations can make incorrect local...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    Multidimensional Meet-in-the-Middle Attack and Its Applications to GOST, KTANTAN and Hummingbird-2

    This paper investigates a new approach to analyze symmetric ciphers by dividing the algorithms to consecutive sub-ciphers and then evaluating them separately. This attack is suitable for ciphers with simple key schedules and having block sizes smaller than key lengths. The authors have successfully applied this multidimensional approach to the...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    Optimally Robust Private Information Retrieval

    The authors give a protocol for multi-server information-theoretic private information retrieval which achieves the theoretical limit for Byzantine robustness. That is, the protocol can allow a client to successfully complete queries and identify server misbehavior in the presence of the maximum possible number of malicious servers. They have implemented their...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    PReFilter: An Efficient Privacy-Preserving Relay Filtering Scheme for Delay Tolerant Networks

    Without direct path, information delivery in sparse Delay Tolerant Networks (DTNs) typically relies on intermittent relays, making the transmission not only unreliable but also time consuming. To make the matter even worse, the source nodes may transmit some encrypted "Junk" information, similar as the spam emails in current mail systems,...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    Enabling Pervasive Healthcare With Privacy Preservation in Smart Community

    Smart community is an emerging Internet of Things application. It supports a variety of high-value automated services such as pervasive healthcare through a multi-hop community network of smart homes in a local residential region. In this paper, the authors study privacy preserving data communication between patients and an online healthcare...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Exploiting Prediction to Enable Secure and Reliable Routing in Wireless Body Area Networks

    In this paper, the authors propose a distributed Prediction-based Secure and Reliable routing framework (PSR) for emerging Wireless Body Area Networks (WBANs). It can be integrated with a specific routing protocol to improve the latter's reliability and prevent data injection attacks during data communication. In PSR, using past link quality...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Cost-Effective Barrier Coverage by Mobile Sensor Networks

    Barrier coverage problem in emerging mobile sensor networks has been an interesting research issue. Existing solutions to this problem aim to decide one-time movement for individual sensors to construct as many barriers as possible, which may not work well when there are no sufficient sensors to form a single barrier....

    Provided By University of Waterloo

  • White Papers // Jul 2011

    An Efficient and Secure User Revocation Scheme in Mobile Social Networks

    Mobile Social Network (MSN) is a promising networking and communication platform for users having similar interests (or attributes) to connect and interact with one another. For many recently introduced secure MSN data communication schemes, attribute-based encryption is often adopted to preserve user privacy. These schemes are mainly to prevent outside...

    Provided By University of Waterloo

  • White Papers // Feb 2009

    A New Achievable Rate for the Gaussian Parallel Relay Channel

    Schein and Gallager introduced the Gaussian parallel relay channel in 2000. They proposed the Amplify-and-Forward (AF) and the Decode-and-Forward (DF) strategies for this channel. For a long time, the best known achievable rate for this channel was based on the AF and DF with time sharing (AF-DF). Recently, a Rematch-and-Forward...

    Provided By University of Waterloo

  • White Papers // Oct 2008

    Cooperative Strategies for the Half-Duplex Gaussian Parallel Relay Channel: Simultaneous Relaying Versus Successive Relaying

    This paper investigates the problem of communication for a network composed of two half-duplex parallel relays with additive white Gaussian noise. Two protocols, i.e., Simultaneous and Successive relaying, associated with two possible relay orderings are proposed. The simultaneous relaying protocol is based on Dynamic Decode and Forward (DDF) scheme. For...

    Provided By University of Waterloo

  • White Papers // Nov 2008

    On the Optimal Design of Wireless Relay Networks

    It is known that the achievable data rate per user can be increased when relays are deployed in wireless networks. However, the drawback of this solution is that some of the network resources should be allocated to the relays. In this paper, the authors consider a two-tier network where all...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    On the Limitations of the Naive Lattice Decoding

    In this paper, the inherent drawbacks of the naive lattice decoding for MIMO fading systems is investigated. The authors show that using the naive lattice decoding for MIMO systems has considerable deficiencies in terms of the rate-diversity trade-off. Unlike the case of maximum-likelihood decoding, in this case, even the perfect...

    Provided By University of Waterloo

  • White Papers // Apr 2008

    On the Diversity-Multiplexing Tradeoff in Multiple-Relay Network

    This paper studies the setup of a multiple-relay network in which K half-duplex multiple-antenna relays assist in the transmission between a/several multiple-antenna transmitter(s) and a multiple-antenna receiver. Each two nodes are assumed to be either connected through a quasi-static Rayleigh fading channel, or disconnected. The authors propose a new scheme,...

    Provided By University of Waterloo

  • White Papers // May 2008

    Robust Joint Source-Channel Coding for Delay-Limited Applications

    In this paper, the authors consider the problem of robust joint source-channel coding over an additive white Gaussian noise channel. They propose a new scheme which achieves the optimal slope of the Signal-To-Distortion (SDR) curve (unlike the previously known coding schemes). Also, they propose a family of robust codes which...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Communication Over MIMO Broadcast Channels Using Lattice-Basis Reduction

    A new viewpoint for adopting the lattice reduction in communication over MIMO broadcast channels is introduced. Lattice basis reduction helps one to reduce the average transmitted energy by modifying the region which includes the constellation points. Also, the outage probability for both cases of fixed-rate users and fixed sum-rate is...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    LLL Reduction Achieves the Receive Diversity in MIMO Decoding

    Diversity order is an important measure for the performance of communication systems over MIMO fading channels. In this paper, the authors prove that in MIMO multiple access systems (or MIMO point-to-point systems with V-BLAST transmission), lattice-reduction-aided decoding achieves the maximum receive diversity (which is equal to the number of receive...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Soft Reconstruction of Speech in the Presence of Noise and Packet Loss

    Exploiting the residual redundancy in a source coder output stream during the decoding process has been proven to be a bandwidth efficient way to combat the noisy channel degradations. In this paper, the authors consider soft reconstruction of speech spectrum, in GSM Adaptive Multi-Rate and IS-641 vocoders, transmitted over a...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Spectral-Efficient Differential Space-Time Coding Using Non-Full-Diverse Constellations

    In this paper, a method is proposed to construct spectral-efficient unitary space-time codes for high-rate differential communications over multiple-antenna channels. Unlike most of the known methods which are designed to maximize the diversity product (the minimum determinant distance), the authors' objective is to increase the spectral efficiency. The simulation results...

    Provided By University of Waterloo

  • White Papers // Feb 2010

    Hummingbird: Ultra-Lightweight Cryptography for Resource-Constrained Devices

    Due to the tight cost and constrained resources of high-volume consumer devices such as RFID tags, smart cards and wireless sensor nodes, it is desirable to employ lightweight and specialized cryptographic primitives for many security applications. Motivated by the design of the well-known Enigma machine, the authors present a novel...

    Provided By University of Waterloo

  • White Papers // Aug 2010

    A Framework Toward a Self-Organizing and Self-Healing Certificate Authority Group in a Content Addressable Network

    Public-key provision in on Internet scale is crucial for securing Peer-To-Peer (P2P) applications. This paper proposes a framework for a self-organizing and self-healing Certificate Authority (CA) in a Content Addressable Network (CAN) that can provide certificates without a centralized Trusted Third Party (TTP). In the authors' framework, a CA group...

    Provided By University of Waterloo

  • White Papers // May 2010

    FPGA Implementations of the Hummingbird Cryptographic Algorithm

    Hummingbird is a new ultra-lightweight cryptographic algorithm targeted for resource-constrained devices like RFID tags, smart cards, and wireless sensor nodes. In this paper, the authors describe efficient hardware implementations of a stand-alone Hummingbird component in Field-Programmable Gate Array (FPGA) devices. They implement an encryption only core and an encryption/decryption core...

    Provided By University of Waterloo

  • White Papers // Nov 2011

    A Cloud-Based Scheme for Protecting Source-Location Privacy Against Hotspot-Locating Attack in Wireless Sensor Networks

    In wireless sensor networks, adversaries can make use of traffic information to locate the monitored objects, e.g., to hunt endangered animals or kill soldiers. In this paper, the authors first define a hotspot phenomenon that causes an obvious inconsistency in the network traffic pattern due to a large volume of...

    Provided By University of Waterloo

  • White Papers // Mar 2010

    Cross-Layer Resource Allocation for Efficient Message Dissemination in Rural Infostation Systems

    In this paper, the authors consider a rural infostation system where power and bandwidth limited infostations is deployed in a large network area with sparsely populated mobile nodes. Direct transmission services are provided to each mobile node, whereas message dissemination services facilitated by relaying are provided to a subgroup of...

    Provided By University of Waterloo

  • White Papers // Jun 2009

    DFMAC: DTN-Friendly Medium Access Control for Wireless Local Area Networks

    In this paper, the authors consider a wireless communication network for both low-speed mobile nodes in densely populated hotspots and high-speed mobile nodes roaming in a large area. Wireless Local Area Networks (WLANs) are deployed in the hotspots, while a delay/Disruption Tolerant Network (DTN) provides services to roaming nodes in...

    Provided By University of Waterloo

  • White Papers // Mar 2012

    Cross-Band Interference Reduction Trade-Offs in SISO and MISO OFDM-Based Cognitive Radios

    Cognitive radio is a promising approach for efficient utilization of radio spectrum. Due to its high spectral efficiency and flexibility, OFDM is considered as a good signaling scheme for cognitive radios. In this paper, the authors investigate the problem of cross-band interference minimization in OFDM-based cognitive systems. Cross-band interference is...

    Provided By University of Waterloo

  • White Papers // Aug 2012

    Decentralized Inverter Control in Microgrids Based on Power Sharing Information Through Wireless Communications

    For the future smart grid, decentralized inverter control is essential in Distributed Generation (DG) micro-grids where a powerful central controller is unavailable for cost and reliability concerns. However, decentralized inverter control suffers from limited system stability mainly because of the lack of communications among different inverters. In this paper, the...

    Provided By University of Waterloo

  • White Papers // Aug 2012

    A Framework for Ubiquitous IP Communications in Vehicle to Grid Networks

    The electrical grid is a critical infrastructure that is slowly moving towards a more reliable and efficient supply system: the Smart Grid. As part of this migration process, a new group of energy-aware and emission-free technologies are being developed. Electric vehicles are a promising technology that belongs to that group....

    Provided By University of Waterloo

  • White Papers // Apr 2012

    FIFO Queueing Policies for Packets With Heterogeneous Processing

    The authors consider the problem of managing a bounded size First-In-First-Out (FIFO) queue buffer, where each incoming unit-sized packet requires several rounds of processing before it can be transmitted out. Their objective is to maximize the total number of successfully transmitted packets. They consider both push-out (when the policy is...

    Provided By University of Waterloo

  • White Papers // Mar 2012

    SUCCESS: A Secure User-Centric and Social-Aware Reputation Based Incentive Scheme for DTNs

    Delay/Disruption Tolerant Networks (DTNs) are self-organized wireless ad-hoc networks, where end-to-end connectivity can not be guaranteed and communications rely on the assumption that the nodes are willing to store-carry-and-forward bundles in an opportunistic way. However, this assumption would be easily violated due to the selfish nodes which are unwilling to...

    Provided By University of Waterloo

  • White Papers // Jun 2012

    Enable Pervasive Healthcare Through Continuous Remote Health Monitoring

    In this paper, the authors introduce a novel Remote Health Monitoring (RHM) system to enable high-quality pervasive healthcare services to users with low delivery delay and reduced costs. They define the RHM architecture and summarize the design considerations. They then present a promising commercialized solution, ViiCare, with system infrastructures and...

    Provided By University of Waterloo

  • White Papers // Feb 2012

    A Secure Payment Scheme With Low Communication and Processing Overhead for Multihop Wireless Networks

    The authors propose RACE, a report-based payment scheme for multi-hop wireless networks to stimulate node cooperation, regulate packet transmission, and enforce fairness. The nodes submit lightweight payment reports (instead of receipts) to the Accounting Center (AC) and temporarily store undeniable security tokens called Evidences. The reports contain the alleged charges...

    Provided By University of Waterloo

  • White Papers // Dec 2011

    Multipath Transmission for Wireless Internet Access - From an End-to-End Transport Layer Perspective

    With the growing demand of Internet services, network operators have put significant efforts to improve network error resilience and efficiency. Since there exist different wired/wireless technologies for Internet access such as Digital Subscriber Line (DSL), Ethernet, and worldwide interoperability for microwave access (WiMax), a mobile host can use multiple access...

    Provided By University of Waterloo

  • White Papers // Jan 2010

    Fast Discrete Fourier Spectra Attacks on Stream Ciphers

    In this paper, the authors present some new results on the selective discrete Fourier spectra attack, introduced first as the recent Ronjom-Helleseth attack and the modifications due to Gong et al. The focal point of this paper is to fill some gaps in the theory of analysis in terms of...

    Provided By University of Waterloo

  • White Papers // May 2009

    Near-Complementary Sequences With Low PMEPR for Peak Power Control in Multicarrier Communications

    A periodic autocorrelation, Boolean functions, Golay complementary sequences, Multi-Carrier Code Division Multiple Access (MC-CDMA), Multicarrier communications, Orthogonal codes, Orthogonal Frequency-Division Multiplexing (OFDM), Peak-to-Average Power Ratio (PAPR), Peak-to-Mean Envelope Power Ratio (PMEPR), Reed-Muller codes, Sequences. Multicarrier communications have recently attracted much attention in wireless applications. The Orthogonal Frequency Division Multiplexing (OFDM)...

    Provided By University of Waterloo

  • White Papers // Jun 2009

    Multiplicative Characters, the Weil Bound, and Polyphase Sequence Families With Low Correlation

    Sequences with low correlation find many applications in wireless communications for acquiring the correct timing information and distinguishing multiple users or channels with low mutual interference. It is desirable that sequences have variable alphabet sizes for adaptive modulation schemes which allow variable data rates in wireless systems according to channel...

    Provided By University of Waterloo

  • White Papers // Jul 2009

    Ultra-Lightweight Cryptography for Low-Cost RFID Tags: Hummingbird Algorithm and Protocol

    Motivated by the design of the well-known Enigma machine, the authors present a novel ultra-lightweight encryption scheme, referred to as Hummingbird, and its applications to a privacy-preserving identification and mutual authentication protocol for RFID applications. Hummingbird can provide the designed security with a small block size and is therefore expected...

    Provided By University of Waterloo

  • White Papers // Jun 2011

    BUPLE: Securing Passive RFID Communication Through Physical Layer Enhancements

    Although RFID systems offer many noteworthy characteristics, security and privacy issues associated with them are not easy to address. In this paper, the authors investigate how to solve the eavesdrop-ping, modification and one particular type of relay attacks toward the tag-to-reader communication in passive RFID systems without requiring lightweight ciphers...

    Provided By University of Waterloo

  • White Papers // Apr 2012

    Implementing Pairings at the 192-Bit Security Level

    The authors implement asymmetric pairings derived from Kachisa-Schaefer-Scott (KSS), Barreto-Naehrig (BN), and Barreto-Lynn-Scott (BLS) elliptic curves at the 192-bit security level. Somewhat surprisingly, they find pairings derived from BLS curves with embedding degree 12 to be the fastest for their serial as well as their parallel implementations. The serial implementations...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Location Privacy Preservation in Collaborative Spectrum Sensing

    Collaborative spectrum sensing has been regarded as a promising approach to enable secondary users to detect primary users by exploiting spatial diversity. In this paper, the authors consider a converse question: could space diversity be exploited by a malicious entity, e.g., an external attacker or an untrusted Fusion Center (FC),...

    Provided By University of Waterloo

  • White Papers // Mar 2012

    Multiagent Coordination in Microgrids Via Wireless Networks

    The future smart grid is expected to be an integration of intelligent microgrids featured by localized electricity generation, storage, and consumption. Wireless communication is a promising means to facilitate pervasive microgrid monitoring and control at a high flexibility and low deployment cost. In order to avoid a single point of...

    Provided By University of Waterloo

  • White Papers // Jan 2012

    Cooperative Cognitive Radio Networking Using Quadrature Signaling

    A quadrature signaling based two-phase cooperation framework for cooperative cognitive radio networking is proposed. By leveraging the degrees of freedom provided by orthogonal modulation, secondary users are able to relay the traffic of primary users and transmit their own in the same time slot without interference. To evaluate the cooperation...

    Provided By University of Waterloo