קולוקוויום וסמינרים

כדי להצטרף לרשימת תפוצה של קולוקוויום מדעי המחשב, אנא בקר בדף מנויים של הרשימה.

קולוקוויום וסמינרים בקרוב

  • CSpecial Talk: Rise and Fall of Binaries

    דובר:
    אביעד כרמל (מדעי המחשב, טכניון)
    תאריך:
    יום שלישי, 23.12.2014, 18:30
    מקום:
    טאוב 7

    We will discuss how binary files are born and created,loaded and executed, about the creation of object files,files linkage and the differences between Linux format (ELF) and Windows format (PE) of such files.

    These will be combined with both information security and attack methods and techniques: what a vicious compiler can do, how viruses and other malwares create problems and more.

  • ceClub:Majority is not Enough: Bitcoin Mining is Vulnerable

    דובר:
    איתי איל (אונ' קורנל)
    תאריך:
    יום רביעי, 24.12.2014, 11:30
    מקום:
    חדר 1007 , בניין מאייר, הפקולטה להנדסת חשמל

    The Bitcoin cryptocurrency records its transactions in a public log called the blockchain. Its security rests critically on the distributed protocol that maintains the blockchain, run by participants called miners. Conventional wisdom had asserted that the protocol was incentive-compatible and secure against colluding minority groups, i.e., it incentivized miners to follow the protocol as prescribed.

    I will show that the Bitcoin protocol is not incentive-compatible by presenting an attack with which colluding miners obtain a revenue larger than their fair share. This attack can have significant consequences for Bitcoin: Rational miners would prefer to join the selfish miners, and the colluding group would increase in size until it became a majority. At this point, the Bitcoin system ceases to be a decentralized currency.

    Selfish mining may be feasible for any group size of colluding miners. However, a practical modification to the Bitcoin protocol can protect against selfish mining pools that command less than 1/4 of the resources. This threshold is lower than the wrongly assumed 1/2 bound, but better than the current reality where a group of any size can compromise the system.

    Bio:
    Ittay is a post-doctoral associate in the Department of Computer Science in Cornell University. He completed his PhD in the Technion in 2012 under the supervision of Prof. Idit Keidar and Prof. Raphi Rom. Ittay's main research interests are the security and scalability of the Blockchain protocol (on which Bitcoin runs) and consistent distributed storage algorithms.

  • Theory Seminar:Inapproximability of Nash Equilibrium

    דובר:
    אביעד רובינשטיין (אונ' ברקלי)
    תאריך:
    יום רביעי, 24.12.2014, 12:30
    מקום:
    טאוב 401

    We prove that finding an epsilon-approximate Nash equilibrium is PPAD-complete for constant epsilon and a particularly simple class of games: polymatrix, degree 3 graphical games, in which each player has only two actions. As corollaries, we also prove similar inapproximability results for Bayesian Nash equilibrium in a two-player incomplete information game with a constant number of actions, for market equilibrium in a non-monotone market, for the generalized circuit problem defined in [Chen, Deng, Teng, 2009], and for approximate competitive equilibrium from equal incomes with indivisible goods.

  • Lessons Learned from and for Requirements Engineering and Building Construction: A Case Study of Requirements Engineering for a Synagogue Kitchen with Use Cases and Scenarios

    דובר:
    Daniel M. Berry - Colloquium Lecture -
    תאריך:
    יום רביעי, 24.12.2014, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20141224_14_30_Berry.html
  • An Algorithmic Approach for Analyzing Social Phenomena

    דובר:
    Sigal Oren - CS-Lecture
    תאריך:
    יום ראשון, 28.12.2014, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20141228_14_30_Oren.html
  • Machine-Learning the Hidden Universal Semantics of Natural Languages

    דובר:
    Omri Abend - CS-Lecture -
    תאריך:
    יום שני, 29.12.2014, 14:30
    מקום:
    חדר 401 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20141229_14_30_Abend.html
  • How to reach unreachable computers

    דובר:
    Prof. Adi Shamir - Colloquium Lecture -
    תאריך:
    יום שלישי, 30.12.2014, 14:30
    מקום:
    חדר Auditorium 1 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20141230_14_30_Shamir.html
  • Fast matrix multiplication: Limitations of the Coppersmith-Winograd approach

    דובר:
    Yuval Filmus - CS-Lecture -
    תאריך:
    יום רביעי, 31.12.2014, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20141231_14_30_Filmus.html
  • Regression Testing of Security Updates Using Deterministic Record/Replay Infrastructure

    דובר:
    איליה קרביץ, הרצאה סמינריונית למגיסטר
    תאריך:
    יום רביעי, 31.12.2014, 15:30
    מקום:
    טאוב 601
    מנחה:
    Dan Tsafrir

    After a software product is shipped, it typically goes into a maintenance phase whereby related software updates are made available form time to time. Such updates should in principle have a positive effect (e.g. fixing bugs), but in reality the users often favor stability over the possible improvements brought by updates, worrying about the possibility of updates somehow adversely affecting their systems. However, leaving security vulnerabilities fixes unapplied might lead to highly undesirable consequences, such as denial of service or system compromise. To lower the risk of an update a staging environment can be created, containing the system replica to which an update is first applied. Then a regression testing is performed, ensuring the updated system still behaves correctly. This testing is usually a laborious manual process, limiting a frequency at which it can be performed. Deterministic Record/Replay is an ability of the system to precisely reproduce its previous execution. Such systems usually employ a combination of state snapshots with an event log, populated during record phase and used to guide the execution of replay phase. In this work we study security updates of a real life systems and applicability of deterministic record/replay techniques for automating regression testing of such updates.

  • Aspects of Submodular Maximization Subject to a Matroid Constraint

    דובר:
    Moran Feldman - CS-Lecture
    תאריך:
    יום חמישי, 1.1.2015, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20150101_14_30_Feldman.html
  • Exponential Separation of Information and Communication

    דובר:
    Gillat Kol- CS-Lecture -
    תאריך:
    יום שני, 5.1.2015, 14:30
    מקום:
    חדר Class 4, Floor 1, טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20150105_14_30_Kol.html
  • Uncertainty, Strategy, and Bounded Rationality

    דובר:
    Reshef Meir - CS-Lecture
    תאריך:
    יום שלישי, 6.1.2015, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20150106_14_30_Reshef.html
  • Parallel Repetition From Fortification

    דובר:
    Dana Moshkovitz - Colloquium Lecture -
    תאריך:
    יום חמישי, 8.1.2015, 12:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20150108_12_30_Moshkovitz.html
  • When Exactly Do Quantum Computers Provide a Speedup?

    דובר:
    Scott Aaronson - Colloquium Lecture
    תאריך:
    יום חמישי, 8.1.2015, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20150108_14_30_Aaronson.html
  • CGGC Seminar: Voronoi diagram of line segments and convex polygons with convex polygon-offset distance functions

    דובר:
    מינאטי דה (מדעי המחשב, טכניון)
    תאריך:
    יום ראשון, 11.1.2015, 14:30
    מקום:
    טאוב 401

    Voronoi diagrams are one of the most powerful data structures in computational geometry. Barequet, Dickerson, and Goodrich [D&CG 2001] introduced the notion of polygon-offset distance function for points. The polygon-offset distance function is more natural than scaling and is useful to model many problems which arise in manufacturing tolerances. Using this distance function, they studied the nearest- and farthest-site Voronoi diagrams of point sites in the plane. In this talk, I will generalize the polygon-offset distance function to convex polygonal objects and present the combinatorial complexity of the nearest - and farthest-site Voronoi diagrams of line segments and convex polygons.

  • Coding For Interactive Communication

    דובר:
    Klim Efremenko - CS-Lecture -
    תאריך:
    יום שני, 12.1.2015, 14:30
    מקום:
    חדר 337-8 טאוב.
    קישור:
    http://www.cs.technion.ac.il/~colloq/20150112_14_30_Efremenko.html