2012 Schedule

  • 04/06/2012 @ : room BC 01
    The I&C Summer Research Institute

    The Summer Research Institute is an I&C Annual Event.  During this period the laboratories focus on an active exchange of research ideas with visiting scholars from renowned international institutions worldwide.  The visitors give one-hour talks on their research, accessible to a broad audience.  This year from 11th-14th June, as part of SuRI, we are organising the Algorithmic Frontiers Workshop.

    Organized by Profs. Christoph Koch, Aleksander Madry, Ruediger Urbanke
  • 04/06/2012 @ 10:30 room BC 01
    Emergent dynamics in a model of visual cortex
    Prof. Lai-Sang Young, New York University, USA

    Abstract :
    This paper proposes that the network dynamics of the mammalian visual cortex are highly structured and strongly shaped by temporally localized barrages of excitatory and inhibitory firing we call `multiple-firing events' (MFEs). Our proposal is based on careful study of a network of spiking neurons built to reflect the coarse physiology of a small patch of layer 2/3 of V1. When appropriately benchmarked this network is capable of reproducing the qualitative features of a range of phenomena observed in the real visual cortex, including orientation tuning, spontaneous background patterns, surround suppression and gamma-band oscillations. Detailed investigation into the relevant regimes reveals causal relationships among dynamical events driven by a strong competition between the excitatory and inhibitory populations. It suggests that along with firing rates, MFE characteristics can be a powerful signature of a regime. Testable predictions based on model observations and dynamical analysis are proposed.

    Organized by SuRI 2012
  • 04/06/2012 @ 14:00 room BC 01
    Reasoning Challenges for Guard Applications
    Dr. Mike Whalen, University of Minnesota Software Engineering Center, USA

    Abstract :
    Guardol is a domain-specific language designed to facilitate the construction of correct network guards operating over tree-shaped data. The Guardol system generates Ada code from Guardol programs and also provides speci cation and automated veri cation support.
    Guard programs and specications are translated to higher order logic, then deductively transformed to a form suitable for a SMT-style decision procedure for recursive functions over tree-structured data.
    The result is that certain complex properties of Guardol programs can be proved fully automatically.  Reasoning challenges for guards involve several aspects:
       - Reasoning about tree structured data
       - Reasoning about strings
       - Reasoning about arrays
    as well as language design to easily support such reasoning.  In this talk we describe how some of these challenges have been addressed, and how several are yet to be addressed.

    Bio :
    Software plays an increasing role in the operation of critical systems. As these systems become more complex, ensuring software correctness becomes much more difficult. I am interested in automated formal techniques for precisely specifying, implementing, and verifying software. To support these activities, I have developed several translation and analysis tools to support formal reasoning and test case generation. I have significant experience in applying formal verification and auto-test generation techniques to production DO178B Level A and B avionics software development efforts.
    I have 15 years experience in software development and analysis, including 10 years experience in Model-Based Development & safety-critical systems. Most of that time has been spent developing simulation, translation, testing, and formal analysis tools for Model-Based Development languages including Simulink, Stateflow, Lustre, and RSML-e. I have led successful formal verification projects on large industrial avionics models, including displays (Rockwell-Collins ADGS-2100 Window Manager), redundancy management and control allocation (AFRL CerTA FCS program) and autoland (AFRL CerTA CPD program). I was the lead developer of the Rockwell-Collins Gryphon tool suite, which can be used for compilation, test-case generation, and formal analysis of Simulink/Stateflow models. This tool suite has been used both for academic research and industrial verification projects.
    I completed my PhD at the University of Minnesota in January, 2005.  As a graduate student, I worked in the Critical Systems Research Group ( CriSys ), where I helped design a synchronous language called Requirements State Machine Language without Events (RSML-e).  My Masters thesis provided the first complete formalization of RSML-e, written in the Z formalism. This formalization has formed the backbone of the RSML-e NIMBUS Simulator and translation tools from RSML-e to model checking and theorem proving tools.  My PhD dissertation re-formalized RSML-e using higher-order abstract syntax and structural operational semantics to create a provably-correct translator from RSML-e to a subset of C.

    Organized by SuRI 2012
  • 06/06/2012 @ 11:00 room BC 01
    A History of Lattice-Based Encryption Schemes
    Dr. Vadim Lyubashevsky, Ecole Normale Superieure, Paris, France

    Abstact:
    Lattice-based cryptography can trace its roots back to the early attempts by researchers to create encryption schemes based on the hardness of the knapsack problem. In this talk, I will describe today's various encryption schemes based on lattices and show the way that they "should have" evolved starting from knapsacks. The talk will cover the NTRU cryptosystem (Hoffstein, Pipher, Silverman 1998), Regev's LWE cryptoscheme (Regev 2005), the recent simple scheme based on Subset Sum (Lyubashevsky, Palacio, Segev 2010), the provably-secure and practical Ring-LWE scheme (Lyubashevsky, Peikert, and Regev 2010), and a provably-secure modification of the NTRU scheme (Stehle, Steinfeld 2011).

    Bio:
    Vadim Lyubashevsky obtained his Ph.D. in Computer Science from the University of California, San Diego in 2008. He is currently an INRIA researcher and a member of the CASCADE cryptography team at ENS Paris. His research mostly focuses on building efficient, provably secure cryptographic schemes based on the hardness of lattice problems. He has co-authored numerous articles in international conferences, among which are the currently most-efficient lattice-based signature and encryption schemes that possess a proof of security.

    Organized by SuRI 2012
  • 06/06/2012 @ 15:30 room BC 01
    Parallel Programming Should Be -- And Can Be -- Deterministic-by-default
    Prof. Vikram S. Adve, University of Illinois at Urbana-Champaign, USA

    Abstract:
    How can we make parallel programming accessible to average developers in the vast commodity applications arena? I will argue that "deterministic-by-default" parallel programming models are part of the answer. With such a model, the programmer is freed from the burden of reasoning about thread interleavings, data races, deadlock, or the intricacies of memory models.  Unfortunately, this goal is challenging to achieve for modern imperative, object-oriented languages. I will describe Deterministic Parallel Java, a deterministic-by-default parallel programming language that guarantees sequential semantics (except where requested otherwise) for explicitly parallel programs.  The deterministic guarantees are achieved using a region-based type and effect system that is a simple extension to base Java. Programmers can combine nondeterministic algorithms with deterministic ones in a data race-free, isolated, manner, with the strongest safety guarantees of any parallel language or system. DPJ also supports the safe use of expressive parallel frameworks.  An interactive tool called DPJizer, under development, enables programmers to port existing Java code to DPJ semi-automatically. We are now exploring how these techniques can be extended to C++, combined with existing parallel languages such as Cilk++ or OpenMP, and applied to large, industrial code bases.

    Bio:
    Vikram Adve is a Professor of Computer Science at the University of Illinois at Urbana-Champaign. His research interests include compilers and programmming languages, and their use for improving software productivity, security and reliability.  His research group developed the LLVM Compiler Infrastructure, a widely distributed and novel compiler framework for 'lifelong' optimization of programs. LLVM is in production use by several companies including Apple, Adobe, Cray, and others, and has replaced GCC as the primary compiler on both iOS 5 and MacOS X. LLVM is also used by a large number of open source projects and research groups.  Adve has been Associate Editor of ACM TOPLAS and Program Chair or Co-chair for ASPLOS, VEE, and LCPC. Adve has  also received the NSF CAREER award, the UIUC Computer Science Department's Outstanding Junior Faculty Award, and paper awards at several conferences including PLDI, SOSP and ICSE, among others.

    Organized by SuRI 2012
  • 07/06/2012 @ 11:15 room BC 01
    A Simple Proof of Threshold Saturation for Coupled Scalar Recursions
    Prof. Henry Pfister

    Abstract:
    It is well-known that belief-propagation (BP) decoding of low-density parity-check (LDPC) codes is suboptimal and that the noise threshold of maximum-a-posteriori (MAP) decoding can be larger than the BP threshold.  Recently, Kudekar et al. showed that regular LDPC ensembles can be "spatially coupled" so that their BP noise threshold saturates to the MAP noise threshold of the original ensemble.  These new ensembles are actually LDPC convolutional (LDPCC) codes and the new result explains an earlier observation by Lentmaier et al. that terminated LDPCC codes allow reliable communication at rates very close to capacity.
    From a statistical physics point of view, LDPC codes can be associated with a collection of electrons whose spins are coupled.  Above the MAP threshold, this system behaves like a liquid.  Below the BP threshold, this system spontaneously crystallizes into the minimum-energy configuration.  If the noise level is between the BP threshold and the MAP threshold, the system behaves like a super-cooled liquid: the system remains a liquid unless there is a seed crystal to start the crystal growth.  Spatial coupling alters the ensemble to include a seed crystal and allows the information to crystallize when the noise is below the MAP threshold.
    This talk presents a simple proof of threshold saturation that applies to a broad class of coupled scalar recursions.  In particular, it applies to the density-evolution (DE) equations of irregular LDPC codes on the erasure channel and the joint iterative decoding of LDPC codes on intersymbol-interference channels with erasure noise.  Extensions to coupled vector recursions will also be discussed along with their connection to universality in multiuser scenarios.

    Organized by SuRI 2012
  • 07/06/2012 @ 14:00 room BC 01
    Provenance Views in Workflows
    Prof. Susan B. Davidson, University of Pennsylvania, USA 

    Abstract:
    The ability to capture, manage and query workflow provenance is increasingly important for scientific as well as business applications. However provenance is a double-edged sword:   Providing complete information in response to provenance queries may not only be overwhelming for the user, but may reveal confidential information.  In this talk, we discuss the use of provenance views to alleviate these problems, and show how they can be used to address privacy concerns as well as to provide varying levels of provenance information, from fine-grained, database-style information to coarse-grained workflow-style information.  We also discuss how provenance queries can be efficiently processed over provenance views.

    Bio:
    Susan B. Davidson received the B.A. degree in Mathematics from Cornell University, Ithaca, NY, in 1978, and the M.A. and Ph.D. degrees in Electrical Engineering and Computer Science from Princeton University, Princeton NJ, in 1980 and 1982. Dr. Davidson is the Weiss Professor and Chair of Computer and Information Science at the University of Pennsylvania, where she has been since 1982.
    Dr. Davidson's research interests include database and web-based systems, scientific data management, and "big data". She co-developed the Kleisli data integration system (with Drs. Buneman, Tannen, Overton, and Wong), which was used for on-the-fly data integration of large genomic datasets. She has also developed techniques for provenance management in scientific workflow systems, including support for search and query, techniques for focusing user attention on "relevant'' provenance information, and marrying database-style and workflow-style provenance management using Pig-Latin to elucidate the function of black-box modules. More recently, she has focused on privacy concerns surrounding the capture and use of provenance information in both databases and workflow systems.
    Dr. Davidson was the founding co-director of the Penn Center for Bioinformatics from 1997-2003, and the founding co-director of the Greater Philadelphia Bioinformatics Alliance. She holds a secondary appointment in the Department of Genetics, is an ACM Fellow, received the Lenore Rowe Williams Award (2002), and was a Fulbright Scholar and recipient of a Hitachi Chair (2004). She currently serves on the VLDB Executive Committee, the CRA Board, and is a member of the CCC Council.

    Organized by SuRI 2012
  • 07/06/2012 @ 15:00 room BC 01
    Towards Domain-Specific Data Management
    Prof. Yanif Ahmad, Johns Hopkins University, Baltimore, USA

    Abstract:
    To overcome scaling challenges, today's computing applications are increasingly exploiting domain-specific properties in their data, computation, and infrastructure models. In data management, specialization of monolithic relational database management systems that cannot service the needs of evermore diverse datasets has led to many new classes of data management systems. In programming languages, embedded domain-specific languages have emerged as a popular technique to express specialized primitives, operators and optimizing toolchains. We argue that data management systems should expose facilities for domain-specific data models, where we can leverage known mathematical properties and representations of our data. Combining mathematical modeling with declarative querying facilitates rich exploratory access to data, and compact data representations with tunable approximation.
    In this talk, I will first present Pulse, a query processor for continuous-time databases based on temporal polynomial models. Pulse uses piecewise polynomials to provide a compact, approximate representation of the input dataset and processes queries by solving simultaneous equation systems in contrast to set-at-a-time record processing. Pulse is able to achieve significant performance improvements by directly processing polynomials prior to discretization, and by exploiting user-defined precision bounds to reduce computation overheads. Beyond polynomial models, I will also discuss our ongoing work with processing queries on statistical models, specifically probabilistic graphical models, applying joint incremental query processing and inference techniques in the BLOG (Bayesian Logic) programming language.

    Bio:
    Yanif Ahmad is an Assistant Professor in the Department of Computer Science at the Johns Hopkins University. His research goals are to enable insightful monitoring of large streaming datasets, and to facilitate easier declarative construction of scalable systems in novel computing applications. In addition to the talk topics, Yanif's ongoing work includes exploring joint database and compiler-style optimizations for large-scale data processing and analytics, and protein data management for a petabyte-scale molecular and drug design dataset in collaboration with the Johns Hopkins Medical School. He received his PhD from Brown University, and has been a postdoctoral associate with the Database Group at Cornell University.

    Organized by SuRI 2012
  • 15/06/2012 @ 11:00 room BC 01
    Ordinal Preference Representation and Aggregation: Game-Theoretic and Combinatorial Aspects of Computational Social Choice
    Dr. Lirong Xia, Harvard University, USA

    Abstract:
    For at least two thousand years, voting has been used as one of the most effective ways to aggregate people’s ordinal preferences.
    In the last 50 years, the rapid development of Computer Science has revolutionize every aspect of the world, including social choice (voting); and meanwhile, social choice has also found applications in many fields in Computer Science, including multiagent systems, recommendation systems, and crowdsourcing. This motivates us to study (1) conceptually, how computational thinking changes the traditional theory of voting, and (2) methodologically, how to better use voting for preference/information aggregation with the help of Computer Science.
    In this talk, I will briefly discuss two research directions, one for each question asked above. The first focuses on investigating how computational thinking affects the game-theoretic aspects of voting. I will discuss the rationale and possibility of using computational complexity to protect voting from a type of strategic behavior of the voters, called manipulation. The second studies a voting setting called Combinatorial Voting, where the set of alternatives is exponentially large and has a combinatorial structure. I will focus on the design and evaluation of novel mechanisms for combinatorial voting that balance computational efficiency and the expressivity of the voting language, in light of some recent developments in Artificial Intelligence.

    Short bio:
    Lirong Xia is a postdoctoral fellow at the Center for Research on Computation and Society at Harvard University. He got a Ph.D. in Computer Science in 2011  and an M.A. in Economics in 2010, both from Duke University. His research focuses on the intersection of computer science and microeconomics, in particular computational social choice, game theory, mechanism design, and prediction markets.

    Organized by SuRI 2012
  • 18/06/2012 @ 11:00 room BC 01
    CamCube - Rethinking the Data Center Cluster
    Dr. Paolo Costa, Imperial College London, UK

    Abstract:
    Since the early days of networks, a basic principle has been that endpoints treat the network as a black box. An endpoint injects a packet with a destination address and the network delivers the packet. This principle has served us well, and has enabled the Internet to scale to billions of devices using networks owned by competing companies and running applications developed by different parties. However, this approach might not be optimal for large-scale Internet data centers, such as those run by Amazon, Google, Microsoft and Facebook, in which all the components are controlled by a single entity. In the CamCube project, we have been looking at a different approach to build data centers, borrowing ideas from the fields of high performance parallel computing, distributed systems and networking. We use a direct-connect topology, similar to those used in HPC, and a novel networking stack, which supports a key-based routing functionality. By providing applications with a more fine-grained control on network resources, CamCube enables increasing performance and reducing development complexity and cluster costs. In this talk, I will provide an overview of the CamCube platform and motivate its peculiar design choices. I will also describe the design and the evaluation of a number of services that we implemented on CamCube. These include a MapReduce service that provides significant higher performance than existing solutions running on traditional clusters.

    Bio:
    Paolo Costa is a fellow of Imperial College London. Before joining Imperial, he spent 2.5 years in the Systems and Networking Group of the Microsoft Research Lab in Cambridge and, prior to that, he had been a Postdoctoral Researcher in the Computer Systems group at Vrije Universiteit Amsterdam. He holds a M. Sc. and Ph.D. degree in Computer Engineering from the Politecnico di Milano, received, respectively, in 2002 and 2006.
    His research interests lie at the intersection of systems and networking with particular focus on large-scale networked systems, ranging from sensor and mobile networks to overlays and, more recently, data centers.

    Organized by SuRI 2012
  • 18/06/2012 @ 14:00 room BC 01
    Social Apps' Data Practices and Privacy Permission Dialogues: A Field Study
    Prof. Jens Grossklags, Pennsylvania State University, USA

    Abstract:
    Several studies have documented the constantly evolving privacy practices of social networking sites and users' misunderstandings about them. Justifiably, users have
    criticized the interfaces to "configure" their privacy preferences as opaque, disjointed, uninformative and ultimately ineffective. The same problems have also plagued the
    constantly growing economy of third-party applications and their equally troubling authentication and authorization dialogues with important options being unavailable
    at installation time and/or widely distributed across the sites' privacy options pages.
    In this talk, I will discuss the results of a field study of the current authorization dialogue for the currently dominant social networking site as well as four canonical designs of installation dialogues which are based on the internationally favored Fair Information Practice Principles (FIPPs). In particular, we study and document the effectiveness of installation-time configuration and awareness-enhancing interface changes when 250 users investigate our experimental application in the privacy of their homes.

    Bio:
    Dr. Grossklags is an Assistant Professor at the College of Information Sciences and Technology at the Pennsylvania State University. He is affiliated with the Security and Risk Analysis program and a member of the steering committee of the Center for the Study of Global Financial Stability. Previously, he served as a Postdoctoral Research Associate at the Center for Information Technology Policy, and as a Lecturer of Computer Science at Princeton University. In 2009, he completed his doctoral dissertation at UC Berkeley's School of Information. While at UC Berkeley, he also obtained master's degrees in Computer Science, and Information Management and
    Systems.
    He is studying information privacy, security, technology policy and networked interactions from a theoretical, empirical and practical perspective. Specifically,
    Dr. Grossklags is motivated to contribute to a better understanding of the current and future marketplace for personal and corporate information, and improved designs of the underlying evolving security infrastructure. His academic work is very cross-disciplinary and utilizes analytic, empirical and experimental methodologies.

    Organized by SuRI 2012
  • 19/06/2012 @ 10:00 room BC 01
    Jekyll & Hyde: a heterogeneous key-value store.
    Dr. Dushyanth Narayanan, Microsoft Research Cambridge

    Abstract:
    Data center hardware is about to get very heterogeneous in terms of CPUs, interconnects, and memory because of developments like ARM-based microservers, custom network fabrics, and hybrid memory cubes all on the horizon. What does this imply for systems design especially for cloud infrastructures?
    In this talk I will describe our recent work on “Jekyll and Hyde”: an in-memory key-value store for asymmetric clusters. The store consists of two in-memory replicas: Jekyll and Hyde. “Jekyll” is a single big memory  server (192 GB in our prototype) that holds one of the replicas.  “Hyde” is a larger number of lower-power machines across which the second replica is sharded. In our prototype we use a cluster of older-generation Intel processors but these could also  be ARM or Atom-based microservers.   By directing transactions and random-access queries to the Jekyll and parallelizable scan-based analytics to the Hyde, we leverage the strengths of each. The transactional workload benefits from the cache coherence and fast interconnect of the Jekyll, while the analytics benefit from the high aggregate bandwidth of the Hyde. An additional benefit is that the scan workloads do not compete for memory bandwidth or pollute the cache of the transactional workloads.
    If time permits I’ll then talk briefly about our ongoing work on locality-preserving partitioning.

    Bio:
    Dushyanth Narayanan is a researcher in the Systems and Networking group at Microsoft Research Cambridge. He has worked on mobile computing, storage, energy-efficiency, and most recently in data center and cloud architectures.

    Organized by SuRI 2012
  • 19/06/2012 @ 11:00 room BC 01
    Viewing the Web as a Distributed Knowledge Base
    Prof. Serge Abiteboul, INRIA Saclay, France

    Abstract:
    Information of interest may be found on the Web in a variety of forms, in many systems, and with different access protocols. A typical user may have information on many devices (smartphone, laptop, TV box, etc.), many systems (mailers, blogs, Web sites, etc.), many social networks (Facebook, Picasa, etc.). This same user may have access to more information from family, friends, associations, companies, and organizations. Today, the control and management of the diversity of data and tasks in this setting are beyond the skills of casual users. Facing similar issues, companies see the cost of managing and integrating information skyrocketing.
    We are interested here in the management of such data. Our focus is not on harvesting all the data of a particular user or a group of users and then managing it in a centralized manner. Instead, we are concerned with the management of Web data in place in a distributed manner, with a possibly large number of autonomous, heterogeneous systems collaborating to support certain tasks.
    Our thesis is that managing the richness and diversity of user-centric data residing on the Web can be tamed using a holistic approach based on a distributed knowledge base. All Web informations are represented as logical facts, and Web data management tasks as logical rules. We discuss Webdamlog, a variant of datalog for distributed data management that we use for this purpose. The automatic reasoning povided by its inference engine, operating over the Web knowledge base, greatly benefits a variety of complex data management tasks that currently require intense work and deep expertise.
    This work is part of the Webdam ERC project.

    Bio:
    Serge Abiteboul, Telecom Paris, PhD computer science, USC Los Angeles, and Thèse d’Etat, University of Paris Sud. He has held professor positions at Stanford and Ecole Polytechnique. He is one of the co-authors of Foundations of Databases, and, recently, of Web Data Management. He co-founded in 2000 a start-up, named Xyleme. He received the 1998 ACM SIGMOD Innovation Award. He has been program chair of a number of conferences including ACM PODS-95, ICALP-94, ICDT-90, ECDL-99 and VLDB-09, ICDE-11, track of WWW-12. He has been awarded in 2008 an ERC Advanced Grant, namely Webdam, on Foundations of Web Data Management. He is a member of the French Academy of Sciences since 2008.

    Organized by SuRI 2012
  • 19/06/2012 @ 14:00 room BC 01
    Privacy and Security for Location-based Applications
    Prof. Urs Hengartner, University of Waterloo, Ontario, Canada

    Abstract:
    Recently, location-based applications have become popular, with applications like Foursquare or Yelp having hundreds of thousands of users. This trend has also highlighted several security and privacy challenges of these applications. I will focus on two such challenges in my talk. First, a user's location is a crucial factor for enabling these applications.  Many applications rely on users to correctly report their location. However, if there is an incentive, users might lie about their location. A location proof architecture enables users to collect proofs for being at a location and applications to validate these proofs. It is essential that proof collection and validation do not violate user privacy. I will introduce a location proof architecture with user privacy as a key design component. Second, matchmaking is a crucial part of location-based social networking applications. It notifies users of nearby people who fulfil some criteria, such as having shared interests or friends, and who are therefore good candidates for being added to a user's social network. A danger of matchmaking is that malicious users may be able to learn any nearby user's profile.  I will introduce a privacy-preserving matchmaking protocol for location-based social networking applications. The protocol lets a potentially malicious user learn only the interests (or some other traits) that he has in common with a nearby user, but no other interests. Finally, I will present an implementation and evaluation of our work on Nexus One smartphones and demonstrate that the work is practical.

    Bio:
    Urs Hengartner is an associate professor in the David R. Cheriton School of Computer Science at the University of Waterloo, Canada.  His research interests are in information privacy and in computer and networks security.  His current research goals are to increase the security of emerging computing environments, such as location-based services, mobile social networking, and electronic voting, and to design privacy-enhancing technologies for people who want to benefit from these environments.  He has a degree in computer science from ETH Zurich and an M.S. and Ph.D. in computer science from Carnegie Mellon.

    Organized by SuRI 2012
  • 19/06/2012 @ 15:00 room BC 01
    Large-Scale Privacy-Preserving Mapping of Human Genomic Sequences on Hybrid Clouds
    Prof. Xiaofeng Wang, Indiana University at Bloomington, USA

    Abstract:
    One of the most important analyses on human DNA sequences is read mapping, which aligns a large number of short DNA sequences (called reads) produced by sequencers to a reference human genome. The analysis involves intensive computation (calculating edit distances over millions upon billions of sequences) and therefore needs to be outsourced to low-cost commercial clouds. This asks for scalable privacy preserving techniques to protect the sensitive information sequencing reads contain. Such a demand cannot be met by the existing techniques, which are either too heavyweight to sustain data-intensive computations or vulnerable to re-identification attacks. In this talk, I describe a new technique that makes an important step towards secure and scalable read mapping on the hybrid cloud, which includes both the public commercial cloud and the private cloud within an organization. Inspired by the famous “seed-and-extend” method, our approach strategically splits a mapping task: the public cloud seeks exact matches between the keyed hash values of short read substrings (called seeds) and those of reference sequences to roughly position reads on the genome; the private cloud extends the seeds from these positions to find right alignments. Our novel seed-combination technique further moves most workload of this task to the public cloud. The new approach is found to work effectively against known inference attacks, and also easily scale to millions of reads.

    Bio:
    Dr. XiaoFeng Wang is an associate professor in the School of Informatics and Computing at Indiana University, Bloomington. He received his Ph.D. in Electrical and Computer Engineering from Carnegie Mellon University in 2004, and has since been a faculty member at IU. Dr. Wang is a recognized active researcher on system, network and data security. His group extensively publishes at leading security venues and vigorously pursues innovative and high-impact research directions.  His current work focuses on privacy issues in processing and dissemination of human genome data and security/privacy issues in Cloud Computing. He is a recipient of 2011 Award for Outstanding Research in Privacy Enhancing Technologies (the PET Award) and the Best Practical Paper Award at the 32nd IEEE Symposium on Security and Privacy. His work frequently receives attentions from the media, including CNN, MSNBC, Slashdot, CNet, PC World, etc.. Dr. Wang has also been actively serving the research community, participating in the program/organization committees of numerous conferences/workshops. His research is supported by the NSF, Department of Homeland Security, the Air Force and Microsoft Research. He was the director for the Security Informatics program including the Master Program in Security at IU in 2010.

    Organized by SuRI 2012
  • 19/06/2012 @ 16:00 room BC 01
    Empiricism vs. the Underground Economy: Recent Trends and Developments
    Dr. Christian Kreibich, International Computer Science Institute (ICSI), Berkeley, USA

    Abstract:
    In his script for "All the President's Men", author William Goldman coined the famous adage "follow the money", giving Woodward and Bernstein crucial advice for their investigation. In the past years, the growth of the Internet has enabled a financially motivated underground marketplace that presents a case perhaps less politically motivated but surely no less thrilling, in which this classic strategy has seen only limited use. In this talk I will describe how following the money trail in this rapidly evolving
    economy has lead us from purely technical botnet infiltrations to experiments that monitor today's "pay-per-install" marketplace for malware distribution, measure the conversion rate of spam, and identify key players as well as bottlenecks in the spam value chain from advertising to product fulfillment.

    Bio:
    Christian Kreibich is a research scientist in the Networking Group at the International Computer Science Institute in Berkeley, California. His research interests focus on the intersection of network architecture, network monitoring, and network security. Christian obtained his Diplom in Computer Science from Technical University Munich in 2002, and his Ph.D. from the University of Cambridge in 2006.

    Organized by SuRI 2012
  • 20/06/2012 @ 10:00 room BC 01
    Computational Insights and the Theory of Evolution
    Prof. Christos Papadimitriou, University California Berkeley, USA

    Abstract:
    I shall discuss recent work (much of it joint with biologists Adi Livnat and Marcus Feldman) on some central problems in Evolution that was inspired and informed by computational ideas. Considerations about the performance of genetic algorithms led to a novel theory on the role of sex in Evolution based on the concept of mixability. And a natural random process on Boolean functions can help us understand better Waddington's genetic assimilation phenomenon, in which an acquired trait becomes genetic, and the emergence of a trait in a population in the absence of mutation.

    Bio:
    I studied in Athens Polytechnic (BS in EE 1972) and Princeton (MS in EE, 1974 and PhD in EECS, 1976).
    Since then, I have taught at Harvard, MIT, Athens Polytechnic, Stanford, and UCSD.
    I came to Berkeley in January 1996 (but I was here also in 1978 as a Miller fellow).
    I am interested in the theory of algorithms and complexity, and its applications to databases, optimization, AI, networks, game theory, and evolution.

    Organized by SuRI 2012
  • 20/06/2012 @ 11:00 room BC 01
    Software packet processing in a 10 Gbit/s world
    Prof. Luigi Rizzo, Università di Pisa, Italy

    Abstract:
    Commodity operating systems can normally handle only a small fraction of the maximum packet rate present on 10 Gbit/s links. Barely enough for the large packets involved in TCP traffic, this does not permit the development of software packet processing nodes in the safe and convenient runtime environment that a general purpose OS makes available.
    In this talk, we will discuss the factors that limit the network I/O performance, and discuss a few solutions to the problem with their pros and cons. We will continue the talk with an overview of a recent packet I/O framework called netmap, which we recently developed.
    ACKNOWLEDGEMENT Work supported by EU FP7 Project "CHANGE" (257422)

    Bio:
    Luigi Rizzo is a Professor of Computer Engineering at the Universita di Pisa, Italy. He has been a research visitor at ICSI (UC Berkeley), Intel Research Cambridge, and Intel Research Berkeley working on various projects related to software routing and traffic monitoring. His research focuses on computer networks and operating systems.
    In particular, he has done some highly cited work on multicast congestion control, FEC-based reliable multicast, network emulation, and more recently on packet scheduling and fast network I/O. Much of this work has been implemented and deployed in popular operating systems and applications, and widely used by the research community. These include the popular "dummynet" network emulator (a standard component of FreeBSD and OSX, and now also available for linux and windows); one of the first publicly available erasure codes for reliable multicast; the qfq packet scheduler; and the netmap framework for fast packet I/O.
    Luigi has been General Chair for SIGCOMM 2006, TPC Co-Chair for SIGCOMM 2009, and TPC member/reviewer for many networking conferences and
    journals. He is currently involved in two EC-funded projects called CHANGE and OPENLAB.

    Organized by SuRI 2012
  • 20/06/2012 @ 16:00 room BC 01
    Exploting Angle-of-Arrival Information for Highly Accurate and Responsive Indoor Localization
    Prof. Kyle Jamieson, University College London, UK

    Abstract:
    Location systems are key to a rich experience for mobile users. When they roam outdoors, mobiles can usually count on a clear GPS signal for an accurate location, but indoors, GPS usually fades, and so up until recently, mobiles have had to rely mainly on rather coarse-grained signal strength readings for location. What has changed
    this status quo is the recent trend of dramatically increasing numbers of antennas at the indoor AP, mainly to bolster capacity and coverage with multiple-input, multiple-output (MIMO) techniques. In the near future, the number of antennas at the access point will increase to meet increasing demands for wireless capacity with MIMO links, spatial division multiplexing, and interference management.  We thus observe an opportunity to revisit the important problem of localization with a fresh perspective.  I will talk about the design and experimental evaluation of ArrayTrack, an indoor location system that uses Angle-of-Arrival information at access points to track wireless clients in real time as they roam about a building. We have prototyped ArrayTrack on the WARP platform, emulating the capabilities of an inexpensive 802.11 wireless access point. Our results show that ArrayTrack can pinpoint 33 clients spread out over an indoor office environment to within a median 36 cm location accuracy.
    Joint work with Jie Xiong.

    Bio:
    Kyle Jamieson is a Lecturer in the Networks research group at University College London. His research interests are in building real-world wireless systems that cut across the boundary of digital communications and networking. He received the PhD in June 2008 from the Massachusetts Institute of Technology (Cambridge, Massachusetts) and is PI on a European Research Council "Ideas" Programe Research Fellowship.

    Organized by SuRI 2012