UC Regents

Displaying 1-40 of 287 results

  • White Papers // Apr 2015

    Per-Core DVFS With Switched-Capacitor Converters for Energy Efficiency in Manycore Processors

    Integrating multiple power converters on-chip improves energy efficiency of many core architectures. Switched Capacitor (SC) DC-DC converters are compatible with conventional CMOS processes, but traditional implementations suffer from limited conversion efficiency. The authors propose a dynamic voltage and frequency scaling scheme with SC converters that achieves high converter efficiency by...

    Provided By UC Regents

  • White Papers // Nov 2014

    Constrained Interpolation for Guided Logic Synthesis

    Craig interpolation is a known method for expressing a target function f as a function of a given set of base functions G. The resulting interpolant represents the dependency function h, such that f

    Provided By UC Regents

  • White Papers // Apr 2014

    m-Inductive Properties of Logic Circuits

    In this paper, the authors introduce the concept of m-inductiveness over a set of signals S in a sequential circuit. The m-inductive property can be used for equivalence-checking or improved sequential optimization. When applied to verification, only equivalency of signals in S and primary outputs need to be checked. When...

    Provided By UC Regents

  • White Papers // Apr 2014

    Enumeration of Irredundant Circuit Structures

    A new approach to Boolean decomposition and matching is proposed. It uses enumeration of all support-reducing decompositions of Boolean functions up to 16 inputs. The approach is implemented in a new framework that compactly stores multiple circuit structures. The method makes use of pre-computations performed offline, before the framework is...

    Provided By UC Regents

  • White Papers // Oct 2013

    Algebraic MACs and Keyed-Verification Anonymous Credentials

    The authors consider the problem of constructing anonymous credentials for use in a setting where the issuer of credentials is also the verifier, or more generally where the issuer and verifier have a shared key. In this setting they can use Message Authentication Codes (MACs) instead of public key signatures...

    Provided By UC Regents

  • White Papers // Oct 2013

    New Trapdoor Projection Maps for Composite-Order Bilinear Groups

    An asymmetric pairing over groups of composite order is a bilinear map e: G1 G2 - GT for groups G1 and G2 of composite order N = pq. The authors observe that a recent construction of pairing-friendly elliptic curves in this setting by the researcher exhibits surprising and unprecedented structure:...

    Provided By UC Regents

  • White Papers // Jun 2013

    Measuring the Practical Impact of DNSSEC Deployment

    DNSSEC extends DNS with a public-key infrastructure, providing compatible clients with cryptographic assurance for DNS records they obtain, even in the presence of an active network attacker. As with many internet protocol deployments, administrators deciding whether to deploy DNSSEC for their DNS zones must perform cost/benefit analysis. For some fraction...

    Provided By UC Regents

  • White Papers // Jun 2012

    Establishing Browser Security Guarantees through Formal Shim Verification

    Web browsers mediate access to valuable private data in domains ranging from health care to banking. Despite this critical role, attackers routinely exploit browser vulnerabilities to exfiltrate private data and take over the underlying system. The authors present QUARK, a browser whose kernel has been implemented and verified in Coq....

    Provided By UC Regents

  • White Papers // Mar 2012

    Logic Synthesis for Disjunctions of Boolean Functions

    In this paper, the authors develop theoretical foundations and present a practical algorithm for optimizing multi-output Boolean function M(x) whose outputs are combined using Boolean OR operator into a single-output Boolean function S(x). The proposed algorithm simplifies the logic structure of function M(x) and may change or remove some of...

    Provided By UC Regents

  • White Papers // Mar 2012

    Sequential Logic Synthesis Using Symbolic Bi-Decomposition

    The authors review some general theorems, proved in a previous paper, about situations when SEC can be reduced to a Combinational Equivalence Checking (CEC) problem. Then, they show how these can be applied to the verification of sequentially clock-gated circuits. A new method based on these theorems was applied to...

    Provided By UC Regents

  • White Papers // Feb 2012

    Multiple-Input Relay Design for More Compact Implementation of Digital Logic Circuits

    Multiple-input relays have been proposed to implement digital logic more compactly than single-input relays. Although a multiple-input relay has a larger footprint than a single-input relay for the same input voltage range, the reduction in device count is advantageous because of the significant area required for the suspension beams and...

    Provided By UC Regents

  • White Papers // Nov 2011

    Characterization of Dynamic SRAM Stability in 45 nm CMOS

    Optimization of SRAM yield using dynamic stability metrics has been evaluated in the past to ensure continued scaling of bit-cell size and supply voltage in future technology nodes. Various dynamic stability metrics have been proposed but they have not been used in practical failure analysis and compared with conventional static...

    Provided By UC Regents

  • White Papers // Aug 2011

    Improved Spectrum Access Control of Cognitive Radios Based on Primary ARQ Signals

    Cognitive radio systems capable of opportunistic spectrum access represent a new paradigm for improving the efficiency of current spectrum utilization. In this paper, the authors present a novel cognitive channel access method based on learning from both primary channel transmissions and the receiver ARQ feedback signals. This new sensing-plus-confirmation scheme...

    Provided By UC Regents

  • White Papers // Aug 2011

    Quality-of-Information Aware Networking for Tactical Military Networks

    In tactical military networks, decisions must often be made quickly based on information at hand. It is a challenge to provide decision makers with a notion of the quality of the information they have, or to provide a method by which decision makers can specify a required quality of information....

    Provided By UC Regents

  • White Papers // Aug 2011

    FERMI: A FEmtocell Resource Management System for Interference Mitigation in OFDMA Networks

    The demand for increased spectral efficiencies is driving the next generation broadband access networks towards deploying smaller cells (femtocells) and sophisticated air interface technologies (Orthogonal Frequency Division Multiple Access or OFDMA). The dense deployment of femtocells however, makes interference and hence resource management both critical and extremely challenging. In this...

    Provided By UC Regents

  • White Papers // Aug 2011

    LEISURE: A Framework for Load-Balanced Network-Wide Traffic Measurement

    Network-wide traffic measurement is of interest to network operators to uncover global network behavior for the management tasks of traffic accounting, debugging or troubleshooting, security, and traffic engineering. Increasingly, sophisticated network measurement tasks such as anomaly detection and security forensic analysis are requiring in-depth fine-grained flow-level measurements. However, performing in-depth...

    Provided By UC Regents

  • White Papers // Jul 2011

    On the Empirical Performance of Self-Calibrating WiFi Location Systems

    The pervasive deployment of 802.11 in modern enterprise buildings has long made it an attractive technology for constructing indoor location services. To this end, a broad range of algorithms have been proposed to accurately estimate location from 802.11 signal strength measurements, some without requiring manual calibration for each physical location....

    Provided By UC Regents

  • White Papers // Jul 2011

    Quasi-Planar Bulk CMOS Technology for Improved SRAM Scalability

    Following Moore's law, transistor density has roughly doubled with each new CMOS technology generation largely due to the steady miniaturization of the transistor. A simple approach for manufacturing quasi-planar bulk MOSFET structures is demonstrated and shown to be effective not only for improving device performance but also for reducing variation...

    Provided By UC Regents

  • White Papers // Jul 2011

    Enhanching in Vehicle Digital Maps Via GPS Crowdsourcing

    In this paper, the authors propose a simple and effective method to extend digital maps with the location and timing of stop-signs and traffic lights in a city, given GPS traces collected by on-road vehicles. Their system finds the location and timing of traffic lights and stop-signs using a small...

    Provided By UC Regents

  • White Papers // Jul 2011

    TouchLogger: Inferring Keystrokes On Touch Screen From Smartphone Motion

    Attacks that use side channels, such as sound and electromagnetic emanation, to infer keystrokes on physical keyboards are ineffective on smartphones without physical keyboards. The authors describe a new side channel, motion, on touch screen smartphones with only soft keyboards. Since typing on different locations on the screen causes different...

    Provided By UC Regents

  • White Papers // Jul 2011

    Cooperative Jamming for Secure Communications in MIMO Relay Networks

    Secure communications can be impeded by eavesdroppers in conventional relay systems. This paper proposes cooperative jamming strategies for two-hop relay networks where the eavesdropper can wiretap the relay channels in both hops. In these approaches, the normally inactive nodes in the relay network can be used as cooperative jamming sources...

    Provided By UC Regents

  • White Papers // Jul 2011

    No Plan Survives Contact: Experience With Cybercrime Measurement

    An important mode of empirical security research involves analyzing the behavior, capabilities, and motives of adversaries. By definition, such measurements cannot be conducted in controlled settings and require "Engagement" directly with adversaries, their infrastructure or their ecosystem. However, the operational complexities required to successfully carry out such measurements are significant...

    Provided By UC Regents

  • White Papers // Jul 2011

    Improving the Way We Design Games for Learning by Examining How Popular Video Games Teach

    One of the reasons why commercial video games are popular is that they effectively teach players how to play the game - in many cases as the player plays the game itself. This paper focuses on how to effectively integrate teaching "How to play a game" with teaching an "Instructional...

    Provided By UC Regents

  • White Papers // Jul 2011

    Variability of Location Management Costs With Different Mobilities and Timer Periods to Update Locations

    In this paper, the authors examine the location management costs in mobile communication networks utilizing the timer-based method. From the study of the probabilities that a mobile terminal changes a number of Location Areas between two calls, they identify a threshold value of 0.7 for the Call-to-Mobility Ratio (CMR) below...

    Provided By UC Regents

  • White Papers // Jul 2011

    Performance and Yield Benefits of Quasi-Planar Bulk CMOS Technology for 6-T SRAM at the 22-nm Node

    The performance and threshold voltage variability of quasi-planar bulk MOSFETs are compared against those of conventional bulk MOSFETs, via Three-Dimensional (3-D) device simulations with gate line-edge roughness and atomistic doping profiles, at 25nm gate length. The nominal performance of Six Transistor (6-T) SRAM cells is studied via 3-D simulation of...

    Provided By UC Regents

  • White Papers // Jun 2011

    BOTMAGNIFIER: Locating Spambots on the Internet

    Unsolicited bulk email (spam) is used by cyber-criminals to lure users into scams and to spread malware infections. Most of these unwanted messages are sent by spam botnets, which are networks of compromised machines under the control of a single (malicious) entity. Often, these botnets are rented out to particular...

    Provided By UC Regents

  • White Papers // Jun 2011

    Measuring Pay-Per-Install: The Commoditization of Malware Distribution

    Recent years have seen extensive diversification of the "Underground economy" associated with malware and the subversion of Internet-connected systems. This trend towards specialization has compelling forces driving it: miscreants readily apprehend that tackling the entire value-chain from malware creation to monetization in the presence of ever-evolving countermeasures poses a daunting...

    Provided By UC Regents

  • White Papers // May 2011

    Authenticated and Misuse-Resistant Encryption of Key-Dependent Data

    This paper provides a comprehensive treatment of the security of Authenticated Encryption (AE) in the presence of key-dependent data, considering the four variants of the goal arising from the choice of universal nonce or random nonce security and presence or absence of a header. The authors present attacks showing that...

    Provided By UC Regents

  • White Papers // May 2011

    Just-in-Time Compilation for FPGA Processor Cores

    Portability benefits have encouraged the trend of distributing applications using processor-independent instructions, a.k.a. bytecode, and executing that bytecode on an emulator running on a target processor. Transparent Just-In-Time (JIT) compilation of bytecode to native instructions is often used to increase application execution speed without sacrificing portability. Recent work has proposed...

    Provided By UC Regents

  • White Papers // May 2011

    Concurrently Secure Computation in Constant Rounds

    The authors study the problem of constructing concurrently secure computation protocols in the plain model, where no trust is required in any party or setup. While the well established UC framework for concurrent security is impossible to achieve in this setting, a meaningful notion of concurrent security based on Super-Polynomial...

    Provided By UC Regents

  • White Papers // May 2011

    RFID Assisted Vehicle Positioning in VANETs

    With technological advancement, recent VANET applications such as safe driving and emergency rescue often demand high position accuracy. Unfortunately, however, conventional localization systems, e.g., GPS, hardly meet new accuracy requirements. To overcome this limitation, this paper proposes an RFID-assisted localization system. The proposed system employs the DGPS concept to improve...

    Provided By UC Regents

  • White Papers // May 2011

    Exploring the Effects of Feed-Forward and Feedback on Information Disclosure and User Experience in a Context-Aware Recommender System

    When disclosing information to a recommender system, users need to trade off its usefulness for receiving better recommendations with the privacy risks incurred through its disclosure. The paper describes a series of studies that will investigate the use of feed-forward and feedback messages to inform users about the potential usefulness...

    Provided By UC Regents

  • White Papers // May 2011

    Some Issues in WSN, MANET and Cellular Security

    In this position paper, the authors address some current limitations and challenges as well as emerging directions in three related areas of secure communication: security in Wireless Sensor Networks - WSNs, security in Mobile Ad hoc NETworks - MANETs, and security in Cellular Phone Networks. Sensors that obtain information by...

    Provided By UC Regents

  • White Papers // May 2011

    Analyzing Interaction Communication Networks in Enterprises and Identifying Hierarchies

    With the proliferation of electronic modes of communication (e.g., e-mails, short messages), a group of people in an enterprise can form several distinct Communication Interaction Networks, or CINs for short. A CIN is essentially a graph representation of "Who talks to whom" among a group of individuals. In this paper,...

    Provided By UC Regents

  • White Papers // May 2011

    Correlated-Input Secure Hash Functions

    The authors undertake a general study of hash functions secure under correlated inputs, meaning that security should be maintained when the adversary sees hash values of many related high-entropy inputs. Such a property is satisfied by a random oracle, and its importance is illustrated by study of the "Avalanche effect,"...

    Provided By UC Regents

  • White Papers // May 2011

    Database-Agnostic Transaction Support for Cloud Infrastructures

    In this paper, the authors present and empirically evaluate the performance of Database-Agnostic Transaction (DAT) support for the cloud. Their design and implementation of DAT is scalable, fault-tolerant, and requires only that the datastore provide atomic, row-level access. Their approach enables applications to employ a single transactional datastore API that...

    Provided By UC Regents

  • White Papers // May 2011

    SAIL: A Scalable Approach for Wide-Area IP Mobility

    The Internet is becoming increasingly mobile, with not only smartphones outnumbering stationary hosts, but also cars, buses, trains and airplanes all coming online. This makes Internet mobility support more important than ever. However, the existing standard mobility support protocols, mainly Mobile IPv6 and NEtwork MObility (NEMO), suffer from triangle routing...

    Provided By UC Regents

  • White Papers // May 2011

    On the Symmetry of User Mobility in Wireless Networks

    In this paper analyzed WLAN - GPS -and synthetic traces that record mobility in a variety of network environments. The authors observe that from a macroscopic level, human mobility is symmetric. In other words, the number of users that move from point A to point B approximates the number of...

    Provided By UC Regents

  • White Papers // May 2011

    A Comparitive Study of Achievability of Security Against Related-Key Attack

    This paper begins with a practical contribution, namely a way to leverage the RKA security of blockciphers to provide RKA security for a suite of high-level primitives. This motivates a more general theoretical question, namely, when is it possible to transfer RKA security from a primitive P1 to a primitive...

    Provided By UC Regents

  • White Papers // May 2011

    GQ: Practical Containment for Measuring Modern Malware Systems

    Measurement and analysis of modern malware systems such as botnets relies crucially on execution of specimens in a setting that enables them to communicate with other systems across the Internet. Ethical, legal, and technical constraints, however, demand containment of resulting network activity in order to prevent the malware from harming...

    Provided By UC Regents

  • White Papers // Oct 2009

    Ziv-Lempel Data Compression

    Large text or graphics files are often compressed in order to save storage space or to speed up transmission when the file is shipped. Most operating systems have compression utilities, and some file transfer programs automatically compress, ship, and uncompress the file, without user intervention. However, a popular compression method...

    Provided By UC Regents

  • White Papers // Sep 2010

    Development And Freedom As Risk Management

    The author has argued that many development and freedom measures such as health, education, political and civil liberties are important constituents of human welfare. The author concur with conjecture that an important reason these measures affect human welfare is because they allow individuals to better cope with risk and uncertainty...

    Provided By UC Regents

  • White Papers // Sep 2009

    Reflections on UNIX Vulnerabilities

    The UNIX operating system was developed in a friendly, collaborative environment without any particular predefined objectives. As it entered less friendly environments, expanded its functionality, and became the basis for commercial, infrastructure, and home systems, vulnerabilities in the system affected its robustness and security. This paper presents a brief history...

    Provided By UC Regents

  • White Papers // Sep 2010

    Ten Years Past and Ten Years From Now

    Ten years ago, computer security was an arcane discipline that many academics did not see as an interesting or deep research area. Today, that perception has changed. Information assurance and computer security touch every aspect of the lives, and the interconnections with more traditional academic disciplines such as analysis of...

    Provided By UC Regents

  • White Papers // Jan 2011

    Induced Churn as Shelter From Routing-Table Poisoning

    Structured overlays are an important and powerful class of overlay networks that has emerged in recent years. They are typically targeted at peer-to-peer deployments involving millions of user-managed machines on the Internet. In this paper the authors address routing-table poisoning attacks against structured overlays, in which adversaries attempt to intercept...

    Provided By UC Regents

  • White Papers // Oct 2010

    A Data-First Architecture for Unstructured Wireless Networks

    The authors have returned to the drawing board to rethink the basic approach to unstructured wireless networks connected or disconnected multi-hop wireless networks whose topology is in a constant state of ux. Current protocols for these networks tend to adopt the Internet protocol stack, originally designed for static, wired networks....

    Provided By UC Regents

  • White Papers // Aug 2010

    The Potential of Cloud Computing: Opportunities and Challenges

    Cloud computing is not a flash in the pan: it has the potential to be as influential and transformative as the microprocessor. It opens genuinely new opportunities for more agile innovation, faster and higher quality research, and agile entrepreneurship, and exposes direct incentives and opportunities for more energy-efficient computing. While...

    Provided By UC Regents

  • White Papers // May 2011

    Database-Agnostic Transaction Support for Cloud Infrastructures

    In this paper, the authors present and empirically evaluate the performance of Database-Agnostic Transaction (DAT) support for the cloud. Their design and implementation of DAT is scalable, fault-tolerant, and requires only that the datastore provide atomic, row-level access. Their approach enables applications to employ a single transactional datastore API that...

    Provided By UC Regents

  • White Papers // Jul 2010

    TurboSync: Clock Synchronization for Shared Media Networks Via Principal Component Analysis With Missing Data

    Clock synchronization in shared media networks is particularly challenging because the operating conditions are dynamic and the resources limited. This paper presents TurboSync, an accurate and bandwidth efficient synchronization scheme. Unlike traditional solutions that synchronize pairs of nodes, TurboSync, is able to synchronize entire node clusters. TurboSync relies on principal...

    Provided By UC Regents

  • White Papers // Jul 2011

    Enhanching in Vehicle Digital Maps Via GPS Crowdsourcing

    In this paper, the authors propose a simple and effective method to extend digital maps with the location and timing of stop-signs and traffic lights in a city, given GPS traces collected by on-road vehicles. Their system finds the location and timing of traffic lights and stop-signs using a small...

    Provided By UC Regents

  • White Papers // Jan 2011

    Running Consistent, Parallel Experiments in Vehicular Environment

    The comparison of different applications and protocols in Vehicular Ad hoc NETworks (VANETs) is a very difficult task. This is mainly due to the nature of VANET, for which it is virtually impossible to replicate the same exact environment in two separate experiments. This paper introduces a flexible experiment structure...

    Provided By UC Regents

  • White Papers // May 2011

    RFID Assisted Vehicle Positioning in VANETs

    With technological advancement, recent VANET applications such as safe driving and emergency rescue often demand high position accuracy. Unfortunately, however, conventional localization systems, e.g., GPS, hardly meet new accuracy requirements. To overcome this limitation, this paper proposes an RFID-assisted localization system. The proposed system employs the DGPS concept to improve...

    Provided By UC Regents

  • White Papers // Jan 2011

    An Integrated Multi-Layer Approach for Seamless Soft Handoff in Mobile Ad Hoc Networks

    The handoff problem in ad hoc networks needs to be treated through an integrated multi-layer approach, due to its major differences with respect to the counterpart in infrastructure-based networks. In this paper, an integrated framework through the cross layer approach is presented to deal with the handoff problem in heterogeneous...

    Provided By UC Regents

  • White Papers // Aug 2010

    DOTS: A Propagation Delay-Aware Opportunistic MAC Protocol for Underwater Sensor Networks

    UnderWater Acoustic Sensor Networks (UW-ASNs) use acoustic links as a means of communications and are accordingly confronted with long propagation delays, low bandwidth, and high transmission power consumption. This unique situation, however, permits multiple packets to concurrently propagate in the underwater channel, which must be exploited in order to improve...

    Provided By UC Regents

  • White Papers // Sep 2010

    Randomized Channel Hopping Scheme for Anti-Jamming Communication

    Jamming attacks have been recently studied as wireless security threats disrupting reliable RF communication in a wireless network. By emitting noise-like signals arbitrarily on the shared wireless medium, a jammer can easily disturb the network. Countermeasures such as Frequency-Hopping Spread Spectrum enable nodes to avoid the jamming attacks by hopping...

    Provided By UC Regents

  • White Papers // Mar 2010

    Energy-Efficient Accelerometer Data Transfer for Human Body Movement Studies

    Wireless sensors with accelerometers are widely used in various studies on human body movements. The most challenging problem in a small body-attachable sensing unit is how to maximize the battery lifetime. Previously, the preferred approach was to reduce the number of transmissions through data compression. Compressed Sensing(C-S) is an emerging...

    Provided By UC Regents

  • White Papers // Jan 2010

    AutoGait: A Mobile Platform that Accurately Estimates the Distance Walked

    AutoGait is a mobile platform that autonomously discovers a user's walking profile and accurately estimates the distance walked. The discovery is made by utilizing the GPS in the user's mobile device when the user is walking outdoors. This profile can then be used both indoors and outdoors to estimate the...

    Provided By UC Regents

  • White Papers // Oct 2009

    Network Coding Multicast Performance When Some Nodes Do Not Code

    Network coding was found to be useful for ad hoc wireless multicast in disruptive channel and connectivity conditions. In heterogeneous networks, comprising teams with different technical preparedness, it is possible that only the radios of the most advanced teams have sufficient resources to network encode/decode. In this case, an interesting...

    Provided By UC Regents

  • White Papers // Jan 2011

    The Effects of MAC Protocols on Ad Hoc Network Communication

    As mobile computing gains popularity, the need for ad hoc routing protocols will continue to grow. There have been numerous simulations comparing the performance of these protocols under varying conditions and constraints. One question that arises is whether the choice of MAC protocol affects the relative performance of the routing...

    Provided By UC Regents

  • White Papers // Jan 2011

    Capacity of Composite Networks: Combining Social and Wireless Ad Hoc Networks

    The authors define composite networks when nodes communicate only with their long-range social contacts and there is no direct link between a node and its long-range contact. Each node has a single long-range contact and all nodes within its transmission range are local contacts for the node. The long-range contact...

    Provided By UC Regents

  • White Papers // Mar 2010

    Opportunistic Interference Management Increases the Capacity of Ad Hoc Networks

    Since the landmark work by Gupta and Kumar on the capacity of wireless ad hoc networks, considerable attention has been devoted to improving or analyzing their results. Ozgur et al. demonstrated that the capacity of random wireless ad hoc network scales linearly with n by allowing nodes to cooperate intelligently...

    Provided By UC Regents

  • White Papers // Dec 2009

    Topology Control for Effective Interference Cancellation in Multi-User MIMO Networks

    In multi-user MIMO networks, receivers decode multiple concurrent signals using Successive Interference Cancellation (SIC). With SIC a weak target signal can be deciphered in the presence of stronger interfering signals. However, this is only feasible if each strong interfering signal satisfies a Signal-to-Noise-plus-Interference Ratio (SINR) requirement. This necessitates the appropriate...

    Provided By UC Regents

  • White Papers // Feb 2010

    Jamming-Resistant Communication: Channel Surfing Without Negotiation

    Channel surfing is an effective method to prevent jamming attacks in wireless communications. In traditional channel surfing schemes, two parties have to negotiate beforehand, in order to agree on the channel switching sequence. However, the negotiation process itself is vulnerable to jamming attacks. In this paper, the authors propose a...

    Provided By UC Regents

  • White Papers // Aug 2010

    Structural Solutions to Dynamic Scheduling for Multimedia Transmission in Unknown Wireless Environments

    In this paper, the authors propose a systematic solution to the problem of scheduling delay-sensitive media data for transmission over time-varying wireless channels. They first formulate the dynamic scheduling problem as a Markov Decision Process (MDP) that explicitly considers the users' heterogeneous multimedia data characteristics (e.g. delay deadlines, distortion impacts...

    Provided By UC Regents

  • White Papers // Jan 2011

    QoS Routing in Wireless Mesh Networks

    Wireless Mesh Networks (WMNs) have been attracting both academia and the industry off late due to their inherent advantages of providing seamless broadband connectivity to community users. Though there has been some recent research on routing in these networks, a preliminary survey of literature tells that not much has been...

    Provided By UC Regents

  • White Papers // Jan 2011

    On the Feasibility of Peer-to-Peer Web Indexing and Search

    This paper discusses the feasibility of peer-to-peer full-text keyword search of the Web. Two classes of keyword search techniques are in use or have been proposed: flooding of queries over an overlay network (as in Gnutella), and intersection of index lists stored in a distributed hash table. The authors present...

    Provided By UC Regents

  • White Papers // Jan 2011

    Request-Aware Scheduling for Busy Internet Services

    Internet traffic is bursty and network servers are often overloaded with surprising events or abnormal client request patterns. This paper studies scheduling algorithms for interactive network services that use multiple threads to handle incoming requests continuously and concurrently. The authors' investigation with applications from Ask Jeeves search shows that during...

    Provided By UC Regents

  • White Papers // Apr 2010

    Resource Management in Multi-Clusters: Cloud Provisioning

    Cloud computing - running large-scale computation- and data-intensive services on inexpensive on-the-fly clusters - has become increasingly popular in recent years due to the advent of MapReduce and similar large-scale data parallel systems. Cloud provisioning, i.e., allocating resources for cluster requests, is the first step toward instantiating such clusters. In...

    Provided By UC Regents

  • White Papers // Oct 2009

    Directional Neighbor Discovery in 60 GHz Indoor Wireless Networks

    The unlicensed 60 GHz band brings the promise of multi-gigabit data rates to support new applications such as high definition video over wireless links. Signal propagation in the 60 GHz band significantly differs from that in the traditionally used 2.4 and 5 GHz bands. The propagation and penetration losses in...

    Provided By UC Regents

  • White Papers // Dec 2009

    Rate Adaptation in Congested Wireless Networks Through Real-Time Measurements

    Rate adaptation is a critical component that impacts the performance of IEEE 802.11 wireless networks. In congested networks, traditional rate adaptation algorithms have been shown to choose lower data-rates for packet transmissions, leading to reduced total network throughput and capacity. A primary reason for this behavior is the lack of...

    Provided By UC Regents

  • White Papers // Oct 2010

    A Quantitative Comparison of Communication Paradigms for MANETs

    Mobile Ad hoc NETworks (MANET) present a challenging area for application development. The combination of mobile nodes and wireless communication can create highly dynamic networks with frequent disconnections and unpredictable availability. Several language paradigms have been applied to MANETs, but there has been no quantitative comparison of alternative approaches. This...

    Provided By UC Regents

  • White Papers // Sep 2010

    Local Estimation of Collision Probabilities in 802.11 WLANs: An Experimental Study

    Current 802.11 networks do not typically achieve the maximum potential throughput despite link adaptation and cross-layer optimization techniques designed to alleviate many causes of packet loss. A primary contributing factor is the difficulty in distinguishing between various causes of packet loss, including collisions caused by high network use, co-channel interference...

    Provided By UC Regents

  • White Papers // Mar 2011

    SenSec: A Scalable and Accurate Framework for Wireless Sensor Network Security Evaluation

    The use of Wireless Sensor Networks (WSNs) is expanding rapidly in a variety of fields. As the use of sensors evolves from merely capturing data to real-time event detection and response, sensor networks must provide accurate and authentic data to guarantee operational integrity. Security solutions are necessary to prevent malicious...

    Provided By UC Regents

  • White Papers // Jan 2011

    HIT: A Human-Inspired Trust Model

    This paper presents a new approach to assign trust levels in ad hoc networks. The system is inspired by the human concept of trust. The trust level considers the recommendation of trustworthy neighbors and their own experience. For the recommendation computation, the authors take into account not only the trust...

    Provided By UC Regents

  • White Papers // Mar 2011

    Secret-Key Generation Using Correlated Sources and Channels

    The authors study the problem of generating a shared secret key between two terminals in a joint source-channel setup - the terminals communicate over a discrete memoryless wiretap channel and additionally the terminals have access to correlated discrete memoryless source sequences. They establish lower and upper bounds on the secret-key...

    Provided By UC Regents

  • White Papers // Jun 2011

    BOTMAGNIFIER: Locating Spambots on the Internet

    Unsolicited bulk email (spam) is used by cyber-criminals to lure users into scams and to spread malware infections. Most of these unwanted messages are sent by spam botnets, which are networks of compromised machines under the control of a single (malicious) entity. Often, these botnets are rented out to particular...

    Provided By UC Regents

  • White Papers // Mar 2011

    The Underground Economy of Spam: A Botmaster's Perspective of Coordinating Large-Scale Spam Campaigns

    Spam accounts for a large portion of the email exchange on the Internet. In addition to being a nuisance and a waste of costly resources, spam is used as a delivery mechanism for many criminal scams and large-scale compromises. Most of this spam is sent using botnets, which are often...

    Provided By UC Regents

  • White Papers // Dec 2010

    EXPOSURE: Finding Malicious Domains Using Passive DNS Analysis

    The Domain Name Service (DNS) plays an important role in the operation of the Internet, providing a two-way mapping between domain names and their numerical identifiers. Given its fundamental role, it is not surprising that a wide variety of malicious activities involve the domain name service in one way or...

    Provided By UC Regents

  • White Papers // May 2011

    SAIL: A Scalable Approach for Wide-Area IP Mobility

    The Internet is becoming increasingly mobile, with not only smartphones outnumbering stationary hosts, but also cars, buses, trains and airplanes all coming online. This makes Internet mobility support more important than ever. However, the existing standard mobility support protocols, mainly Mobile IPv6 and NEtwork MObility (NEMO), suffer from triangle routing...

    Provided By UC Regents

  • White Papers // Oct 2009

    On the Economics of Anonymity

    Decentralized anonymity infrastructures are still not in wide use today. While there are technical barriers to a secure robust design, the authors' lack of understanding of the incentives to participate in such systems remains a major roadblock. Here the authors explore some reasons why anonymity systems are particularly hard to...

    Provided By UC Regents