UC Regents

Displaying 1-40 of 311 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

    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

    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 // 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 // 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

    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 // 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 // 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 // Jan 2011

    Understanding Congestion in IEEE 802.11b Wireless Networks

    The growing popularity of wireless networks has led to cases of heavy utilization and congestion. In heavily utilized wireless networks, the wireless portion of the network is a major performance bottleneck. Understanding the behavior of the wireless portion of such networks is critical to ensure their robust operation. This understanding...

    Provided By UC Regents

  • White Papers // Feb 2010

    PRoPHET+: An Adaptive PRoPHET-Based Routing Protocol for Opportunistic Network

    The authors propose PRoPHET+, a routing scheme for opportunistic networks designed to maximize successful data delivery rate and minimize transmission delay. PRoPHET+ computes a deliverability value to determine the routing path for packets. Deliverability is calculated using a weighted function consisting of evaluations of nodes' buffer size, power, location, popularity,...

    Provided By UC Regents

  • White Papers // Jan 2011

    Identity-Based Access Control for Ad Hoc Groups

    The proliferation of group-centric computing and communication motivates the need for mechanisms to provide group access control. Group access control includes mechanisms for admission as well as revocation/ eviction of group members. Particularly in ad hoc groups, such as Peer-To-Peer (P2P) systems and Mobile Ad hoc NETworks (MANETs), secure group...

    Provided By UC Regents

  • White Papers // May 2010

    Decentralized Cognitive Radio Control Based on Inference From Primary Link Control Information

    This paper on cognitive radio access ventures beyond the more traditional "Listen-before-talk" paradigm that underlies many cognitive radio access proposals. The authors exploit the bi-directional interaction of most primary communication links. By intelligently controlling their access parameters based on the inference from observed link control signals of Primary User (PU)...

    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 // Feb 2010

    An Evaluation of Peer-to-Peer File Sharing on the Android Mobile Platform

    Handheld mobile devices are at the forefront of technology today. Every manufacturer is looking to reduce the size of their product while increasing its usability at the same time. With the growing popularity of third party applications (apps developed by individual users), there is almost no limit to what a...

    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 // 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 // Apr 2010

    Antenna Selection for Opportunistic Interference Management in MIMO Broadcast Channels

    Multi-user diversity scheme is an alternative approach to more traditional techniques like Time Division Multiple Access (TDMA) to increase the capacity of wireless cellular networks. The main idea behind this approach is that the base station selects a mobile user with the best channel condition by taking advantage of the...

    Provided By UC Regents

  • White Papers // Feb 2010

    Capacity of Wireless Networks With Heterogeneous Traffic Under Physical Model

    The throughput capacity of wireless ad hoc networks is derived when the traffic is heterogeneous but the node distribution is homogeneous. For the heterogeneous traffic the authors consider two types of traffic in the network, namely, unicast and data gathering communications. There are k sources that send different data to...

    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 // Mar 2011

    Quality-Oriented Video Delivery Over LTE Using Adaptive Modulation and Coding

    Long Term Evolution (LTE) is emerging as a major candidate for 4G cellular networks to satisfy the increasing demands for mobile broadband services, particularly multimedia delivery. MIMO (Multiple Input Multiple Output) technology combined with OFDMA and more efficient Modulation/Coding Schemes (MCS) are key physical layer technologies in LTE networks. However,...

    Provided By UC Regents

  • White Papers // Oct 2010

    Empirical Modeling and Estimation of End-to-End VoIP Delay Over Mobile Multi-Hop Wireless Networks

    Voice-over-IP (VoIP) systems face the following two general constraints: a stringent end-to-end delay constraint of at most 500 ms has to be satisfied, including not only the end-to-end networking delay, but also delays incurred due to encoding, decoding, as well as play-out buffer delays. An end-to-end Packet Delivery Ratio (PDR)...

    Provided By UC Regents

  • White Papers // Jan 2011

    CaDAR: An Efficient Routing Algorithm for Wireless-Optical Broadband Access Network

    Hybrid Wireless-Optical Broadband Access Network (WOBAN) is a combination of wireless and optical network to optimize the cost and performance of an access network. Wireless nodes collect traffic from end users and carry them to the optical part of a WOBAN using multiple hops accumulating delay at each wireless node....

    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 // Jan 2010

    Bit Allocation of WWAN Scalable H.264 Video Multicast for Heterogeneous Cooperative Peer-to-Peer Collective

    By exploiting multiple network interfaces on one device, e.g., Wireless Wide Area Network (WWAN) and Wireless Local Area Network (WLAN), peers receiving different subsets of WWAN broadcast/multicast packets can perform Cooperative Peer-to-peer Repair (CPR) by exchanging received WWAN packets with their local WLAN peers. This effectively improves the transmission success...

    Provided By UC Regents

  • White Papers // Aug 2010

    Fast Mixing of Parallel Glauber Dynamics and Low-Delay CSMA Scheduling

    Glauber dynamics is a powerful tool to generate randomized, approximate solutions to combinatorially difficult problems. It has been used to analyze and design distributed CSMA (Carrier Sense Multiple Access) scheduling algorithms for multi-hop wireless networks. In this paper, the authors derive bounds on the mixing time of a generalization of...

    Provided By UC Regents

  • White Papers // Jun 2009

    Dynamic Test Generation To Find Integer Bugs in x86 Binary Linux Programs

    Recently, integer bugs, including integer overflow, width conversion, and signed/unsigned conversion errors, have risen to become a common root cause for serious security vulnerabilities. The authors introduce new methods for discovering integer bugs using dynamic test generation on x86 binaries, and they describe key design choices in efficient symbolic execution...

    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 // 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 // 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 // Jan 2011

    AppScale: Open-Source Platform-as-a-Service

    AppScale is a scalable, distributed, and fault tolerant cloud runtime system that the authors have developed at the University of California, Santa Barbara as part of their research into the next generation of programming systems. In particular, AppScale is a cloud platform, i.e. a Platform-as-a-Service (PaaS) cloud fabric that executes...

    Provided By UC Regents

  • White Papers // Aug 2010

    A static, packer-agnostic Filter to detect similar malware samples

    The steadily increasing number of malware variants is becoming a significant problem, clogging the input queues of automated analysis tools and polluting malware repositories. The generation of malware variants is made easy by automatic packers and polymorphic engines, which can produce many distinct versions of a single executable using compression...

    Provided By UC Regents

  • White Papers // Oct 2010

    A Comprehensive Framework for Secure Query Processing on Relational Data in The Cloud

    Data security in the cloud is a big concern that blocks the widespread use of the cloud for relational data management. First, to ensure data security, data confidentiality needs to be provided when data resides in storage as well as when data is dynamically accessed by queries. Prior works on...

    Provided By UC Regents

  • White Papers // Mar 2011

    Memory Management for Multi-Language Multi-Runtime Systems on Multi-Core Architectures

    To manage the increasing complexity of software, developers employ a number of different strategies. These include using high-level, type-safe, object-oriented programming languages, executing applications within Managed Runtime Environments (MREs), modularizing software into independent isolated components, and maximizing programmer productivity by implementing each component in the most-suitable language. Moreover, administrators and...

    Provided By UC Regents

  • White Papers // Jul 2010

    Collection of Time series of appetite-related sensations using a handheld computer: a case study

    The authors present a case study in the design and subsequent use of "OKMO", a software program for the quantitative assessment of subjective appetite-related sensations, using a visual scale and running on a handheld computing device. OKMO runs on inexpensive Palm devices (PalmOS 4), and was built using only free...

    Provided By UC Regents

  • White Papers // Oct 2010

    The Combinatorial BLAS: Design, Implementation, and Applications

    This paper presents a scalable high-performance software library to be used for graph analysis and data mining. Large combinatorial graphs appear in many applications of high-performance computing, including computational biology, informatics, analytics, web search, dynamical systems, and sparse matrix methods. Graph computations are difficult to parallelize using traditional approaches due...

    Provided By UC Regents

  • White Papers // Sep 2010

    Scalable Nearest Neighbors with Guarantees in Large and Composite Networks

    The authors address the problem of k Nearest Neighbor (kNN) search in networks, according to a random walk proximity measure called Effective Importance. Their approach retrieves the exact top neighbors at query time without relying on off-line indexing or summaries of the entire network. This makes it suitable for very...

    Provided By UC Regents

  • White Papers // Jul 2010

    Concurrent Collection as an Operating System Service for Cross-Runtime Cross-Language Memory Management

    The authors present GC-as-a-Service (GaS), a cross-runtime, cross-language Garbage Collection (GC) library that can be used to simplify the implementation of runtime systems, and that exploits available multicore technologies. GaS decouples GC from other runtime components and exposes a fine-grain API for use by GC-cooperative runtimes of different programming languages...

    Provided By UC Regents

  • White Papers // Aug 2010

    Understanding the Potential of Interpreter-based Optimizations for Python

    The increasing popularity of scripting languages as general purpose programming environments calls for more efficient execution. Most of these languages, such as Python, Ruby, PHP, and JavaScript are interpreted. Interpretation is a natural implementation given the dynamic nature of these languages and interpreter portability has facilitated wide-spread use. In this...

    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 // 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 // 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 // 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