UC Regents

Displaying 1-40 of 348 results

  • 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 // 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

    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 // 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

    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 // 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 // Apr 2011

    Seeker - A Bandwidth-Based Association Control Framework for Wireless Mesh Networks

    The rapid deployment of wireless mesh networks across universities and enterprises, and the pervasiveness of mobile devices equipped with Wi-Fi connectivity, has resulted in a scenario wherein end users have the option to choose from a multitude of access points at any given location. Moreover, with the increasing availability of...

    Provided By UC Regents

  • White Papers // Apr 2011

    Programming Support for Distributed Optimization and Control in Cyber-Physical Systems

    Large-scale actuator control problems in Cyber-Physical Systems (CPSs) are often expressed within the networked optimization model. While significant advances have taken place in optimization techniques, their widespread adoption in practical implementations is impeded by the complexity of inter-node coordination and lack of programming support that is necessary for sharing information...

    Provided By UC Regents

  • White Papers // Apr 2011

    (Im)Possible Frontiers: A Comment

    The existence of mean-variance efficient positive portfolios - portfolios with no negative weights - is a key requirement for equilibrium in the Capital Asset Pricing Model (CAPM). Brennan and Lo (2010) define an "Impossible frontier" as a frontier on which all portfolios have at least one negative weight. They prove...

    Provided By UC Regents

  • White Papers // Apr 2011

    Collusion-Resilient Quality of Information Evaluation Based on Information Provenance

    The quality of information is crucial for decision making in many dynamic information sharing environments such as sensor and tactical networks. Information trustworthiness is an essential parameter in assessing the information quality. In this paper, the authors present a trust model to evaluate the trustworthiness of information as well as...

    Provided By UC Regents

  • White Papers // Apr 2011

    Digitizing Physical Objects in the Home

    Technology in the home has brought about a number of changes in the way things are being done. Particularly interesting is the question as to whether some ways of doing activities are now being replaced given the availability of technology at an affordable cost. The ownership of a home computer...

    Provided By UC Regents

  • White Papers // Apr 2011

    Systemic Sovereign Credit Risk: Lessons From The U.S. And Europe

    The authors study the nature of systemic sovereign credit risk using CDS spreads for the U.S. Treasury, individual U.S. states, and major European countries. Using a multifactor affine framework that allows for both systemic and sovereign-specific credit shocks, they find that there is considerable heterogeneity across U.S. and European issuers...

    Provided By UC Regents

  • White Papers // Mar 2011

    Database Scalability, Elasticity, and Autonomy in the Cloud

    The proliferation of technology in the past two decades has created an interesting dichotomy for users. There is very little disagreement that an individual's life is significantly enriched as a result of easy access to information and services using a wide spectrum of computing platforms such as personal workstations, laptop...

    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 // Mar 2011

    Learning From Repetitive Acquisitions: Evidence From The Time Between Deals

    Repetitive acquisitions involve benefits and costs. Benefits accrue from learning about the takeover process while costs involve integrating the combined firms. These benefits and costs are not directly observable from outside the firm but this paper proposes a simple model to infer their relative importance from the time between successive...

    Provided By UC Regents

  • White Papers // Mar 2011

    Usability of Display-Equipped RFID Tags for Security Purposes

    Recent emergence of high-end RFID tags capable of performing public key operations enables some new applications in commerce (e.g., RFID-enabled credit cards) and security (e.g., ePassports and access control badges). While the use of public key cryptography mitigates many difficult security issues, certain important usability-related issues remain, particularly, when RFID...

    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 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

    Decentralized Cognitive MAC for Dynamic Spectrum Access

    The authors consider the problem of opportunistic Dynamic Spectrum Access (DSA) in an ad hoc network in which unlicensed secondary users communicate through channels not used by the primary users. Decentralized cognitive medium access control protocols are presented that allow secondary users to recognize spectrum opportunity and transmit based on...

    Provided By UC Regents

  • White Papers // Aug 2009

    Geo-Based Inter-Domain Routing (GIDR) Protocol for Manets

    Inter-domain routing for MANETs (Mobile Ad Hoc NETworks) draws increasing attention because of military and vehicular applications. The existing Border Gateway Protocol (BGP) is the de facto inter-domain routing protocol for the Internet. But BGP is not applicable to MANETs because the BGP design is based on a static Internet...

    Provided By UC Regents

  • White Papers // Nov 2010

    MobiCom 2010 Poster: Frequency Quorum Rendezvous for Fast and Resilient Key Establishment Under Jamming Attack

    Jamming attacks have been studied as wireless security threats disrupting reliable RF communication in a wireless network. Existing countermeasures often make use of spread-spectrum techniques such as Frequency Hopping Spread Spectrum and Direct Sequence Spread Spectrum. Communication parties rely on a pre-shared common key (hopping sequence or spread code) which...

    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 // Sep 2009

    A Distributed Numerical Approach to Interference Alignment and Applications to Wireless Interference Networks

    Recent results establish the optimality of interference alignment to approach the Shannon capacity of interference networks at high SNR. However, the extent to which interference can be aligned over a finite number of signaling dimensions remains unknown. Another important concern for interference alignment schemes is the requirement of global channel...

    Provided By UC Regents

  • White Papers // Mar 2010

    On the Minimum Side Information of MIMO Broadcast Channel

    The authors introduce a technique to achieve Dirty Paper Coding (DPC) capacity asymptotically with minimum feedback required reported to date in literature. Their approach called interference management, is based on a new multi-user diversity scheme designed for wireless cellular networks. When there are K antennas at the base station with...

    Provided By UC Regents

  • White Papers // Apr 2010

    Impact of Multi-Packet Transmission and Reception on Throughput Capacity of Wireless Ad Hoc Networks

    The authors study the capacity of random wireless ad hoc networks when nodes are capable Multi-Packet Transmission and Reception (MPTR). This paper extends the unified framework of (n, m and k)-cast by Wang et al. with Single-Packet Reception (SPR) capability for each node to MPTR. (n, m and k)-cast considers...

    Provided By UC Regents

  • White Papers // Mar 2010

    The Capacity of Multihop Relay Wireless Networks

    The throughput capacity of wireless ad hoc networks is an important topic that has been studied extensively in the literature. Most of these studies are based on the assumption that all the nodes in the network are either source or destination. However, there is another important group of networks where...

    Provided By UC Regents

  • White Papers // Dec 2009

    The Capacity of Ad Hoc Networks With Heterogeneous Traffic Using Cooperation

    The authors study the scaling laws for wireless ad hoc networks in which the distribution of n nodes in the network is homogeneous but the traffic they carry is heterogeneous. They present a separation theorem for heterogeneous traffic showing that the optimum order throughput capacity can be attained in a...

    Provided By UC Regents

  • White Papers // Mar 2010

    ElasTraS: An Elastic, Scalable, and Self Managing Transactional Database for the Cloud

    Cloud computing has emerged as a pervasive platform for deploying scalable and highly available Internet applications. To facilitate the migration of data-driven applications to the cloud: elasticity, scalability, fault-tolerance, and self-manageability (henceforth referred to as cloud features) are fundamental requirements for DataBase Management Systems (DBMS) driving such applications. Even though...

    Provided By UC Regents

  • White Papers // Feb 2010

    Key-Value Datastores Comparison in AppScale

    The authors present a simple framework that employs a single API - the Datastore API from the Google App Engine cloud computing platform - to interface to different open source distributed database technologies in use today. They use the framework to "Plug in" different databases to the API so that...

    Provided By UC Regents

  • White Papers // Oct 2009

    Vshmem: Shared-Memory OS-Support for Multicore-based HPC systems

    As a result of the huge performance potential of multi-core microprocessors, HPC infrastructures are rapidly integrating them into their architectures in order to expedite the performance growth of the next generation HPC systems. However, as the number of cores per processor increase to 100 or 1000s of cores, they are...

    Provided By UC Regents

  • White Papers // Aug 2009

    Verification of String Manipulating Programs Using Multi-Track Automata

    Verification of string manipulation operations is a crucial problem in computer security. The authors present a new symbolic string verification technique that can be used to prove that vulnerabilities that result from improper string manipulation do not exist in a given program. They formally characterize the string verification problem as...

    Provided By UC Regents

  • White Papers // Aug 2009

    Tackling Bidder Collusion in Dynamic Spectrum Auctions (Extended)

    Dynamic spectrum auction is an effective solution to manage spectrum across many small networks. As the number of participants grows, collusion poses a serious threat to auction performance. Small groups of colluding bidders can make use of the interference constraints to manipulate auction outcomes, leading to unfair spectrum distribution and...

    Provided By UC Regents

  • White Papers // Jul 2009

    Mining the Network Behavior of Bots

    A botnet is a network of compromised hosts that fulfills the malicious intents of an attacker. Once installed, a bot is typically used to steal sensitive information, send SPAM, perform DDoS attacks, and other illegal activities. Research in botnet detection has been quite prolific in the past years, producing detection...

    Provided By UC Regents

  • White Papers // Jun 2009

    Generating Vulnerability Signatures for String Manipulating Programs Using Automata-based Forward and Backward Symbolic Analyses

    Given a program and an attack pattern (specified as a regular expression), the authors automatically generate string-based vulnerability signatures, i.e., a characterization that includes all malicious inputs that can be used to generate attacks. They use an automata-based string analysis framework. Using forward reachability analysis they compute an over-approximation of...

    Provided By UC Regents

  • White Papers // Jun 2009

    Spectrum Allocation for Frequency-Agile Radio Networks under Physical Interference Models

    Spectrum frequency allocation problems are fundamental problems in wireless spectrum auctions and wireless LAN management. Due to their complexity, most existing proposals simplify the allocation problems by reducing physical interference to a graph-based interference model. In this paper, the authors propose LIGHTHOUSE, a new line of efficient approximation algorithms that...

    Provided By UC Regents

  • White Papers // Mar 2009

    Multicasting in the Hypercube, Chord and Binomial Graphs

    Multicasting is a communication primitive that allows a node in a network to send a message to multiple destination nodes. There are many ways in which multicasting can be implemented. For example, when an e-mail is sent to k destinations, e-mailing systems make k copies of the message and send...

    Provided By UC Regents

  • White Papers // Jun 2009

    In-Depth Evaluation of Popular Interest Point Detectors on Video Streams

    The authors present an in-depth evaluation of popular interest point detectors, which, in contrast to existing evaluations, is targeted towards the application in visual tracking and augmented reality. In particular, candidate algorithms, testbed, and performance criteria are chosen with respect to the application of visual tracking. They evaluate the impact...

    Provided By UC Regents

  • White Papers // Apr 2009

    TRUST:A General Framework for Truthful Double Spectrum Auctions (Extended)

    The authors design truthful double spectrum auctions where multiple parties can trade spectrum based on their individual needs. Open, market-based spectrum trading motivates existing spectrum owners (as sellers) to lease their selected idle spectrum to new spectrum users, and provides new users (as buyers) the spectrum they desperately need. The...

    Provided By UC Regents

  • White Papers // Apr 2009

    Strongly Regular Grammars and Regular Approximation of Context-Free Languages

    The authors consider algorithms for approximating context - free grammars by regular grammars, making use of Chomsky's characterization of non-self-embedding grammars as generating regular languages and a transformation by Mohri and Nederhof on sets of mutually recursive non-terminals. They give an exposition of strongly regular grammars and this transformation, and...

    Provided By UC Regents

  • White Papers // Aug 2009

    Thread Cooperation in Multicore Architectures for Frequency Counting Over Multiple Data Streams

    Many real-world data stream analysis applications such as network monitoring, click stream analysis and others require combining multiple streams of data arriving from multiple sources. This is referred to as multi-stream analysis. To deal with high stream arrival rates, it is desirable that such systems be capable of supporting very...

    Provided By UC Regents

  • White Papers // Jun 2009

    Anonymizing Edge-Weighted Social Network Graphs

    The increasing popularity of social networks has initiated a fertile research area in information extraction and data mining. Although such analysis can facilitate better understanding of sociological, behavioral, and other interesting phenomena, there is growing concern about personal privacy being breached, thereby requiring effective anonymization techniques. If the authors consider...

    Provided By UC Regents

  • White Papers // Jan 2009

    On Stateless Multicounter Machines

    The authors investigate the computing power of stateless multicounter machines with reversal-bounded counters. Such a machine hasm-counters operating on a one-way input delimited by left and right end markers. The move of the machine depends only on the symbol under the input head and the signs of the counters (zero...

    Provided By UC Regents

  • White Papers // Nov 2008

    Clouded Data: Comprehending Scalable Data Management Systems

    Managing petabytes of data for millions of users has been a challenge for big internet based enterprises such as Google, Yahoo!, and Amazon. Even though database management systems have a long history of managing enterprise level data and information, they are deemed to be unsuitable in this context. This resulted...

    Provided By UC Regents

  • White Papers // Nov 2008

    Gaussian Elimination Based Algorithms on the GPU

    The authors implemented and evaluated several Gaussian elimination based algorithms on Graphic Processing Units (GPUs). These algorithms, LU decomposition without pivoting, all-pairs shortest-paths, and transitive closure, all have similar data access patterns. The impressive computational power and memory bandwidth of the GPU make it an attractive platform to run such...

    Provided By UC Regents

  • White Papers // Sep 2008

    Improving Anonymity using Social Links

    Protecting user privacy in network communication is vital in today's open networking environment. Current anonymous routing protocols provide anonymity by forwarding traffic through a static path of randomly selected relay nodes. In practice, however, malicious relays can perform passive logging attacks to compromise the anonymity of a flow. This degradation...

    Provided By UC Regents

  • White Papers // Sep 2008

    Rome: Performance and Anonymity using Route Meshes

    Deployed anonymous networks such as Tor focus on delivering messages through end-to-end paths with high anonymity. Selection of routers in the anonymous path construction is either performed randomly, or relies on self-described resource availability from each router, which makes the system vulnerable to low-resource attacks. In this paper, the authors...

    Provided By UC Regents

  • White Papers // Jan 2011

    Efficient Algorithms and Routing Protocols for Handling Transient Single Node Failures

    Single node failures represent more than 85% of all node failures in the today's large communication networks such as the Internet. Also, these node failures are usually transient. Consequently, having the routing paths globally recomputed does not pay off since the failed nodes recover fairly quickly, and the recomputed routing...

    Provided By UC Regents