TY - THES AB - FPGAs, systems on chip and embedded systems are nowadays irreplaceable. They combine the computational power of application specific hardware with software-like flexibility. At runtime, they can adjust their functionality by downloading new hardware modules and integrating their functionality. Due to their growing capabilities, the demands made to reconfigurable hardware grow. Their deployment in increasingly security critical scenarios requires new ways of enforcing security since a failure in security has severe consequences. Aside from financial losses, a loss of human life and risks to national security are possible. With this work I present the novel and groundbreaking concept of proof-carrying hardware. It is a method for the verification of properties of hardware modules to guarantee security for a target platform at runtime. The producer of a hardware module delivers based on the consumer's safety policy a safety proof in combination with the reconfiguration bitstream. The extensive computation of a proof is a contrast to the comparatively undemanding checking of the proof. I present a prototype based on open-source tools and an abstract FPGA architecture and bitstream format. The proof of the usability of proof-carrying hardware provides the evaluation of the prototype with the exemplary application of securing combinational and bounded sequential equivalence of reference monitor modules for memory safety. AU - Drzevitzky, Stephanie ID - 586 TI - Proof-Carrying Hardware: A Novel Approach to Reconfigurable Hardware Security ER - TY - GEN AU - Plessl, Christian AU - Platzner, Marco AU - Agne, Andreas AU - Happe, Markus AU - Lübbers, Enno ID - 587 TI - Programming models for reconfigurable heterogeneous multi-cores ER - TY - CONF AB - We come up with a digital rights management (DRM) concept for cloud computing and show how license management for software within the cloud can be achieved in a privacy-friendly manner. In our scenario, users who buy software from software providers stay anonymous. At the same time, our approach guarantees that software licenses are bound to users and their validity is checked before execution. We employ a software re-encryption scheme so that computing centers which execute users’ software are not able to build user profiles—not even under pseudonym—of their users. We combine secret sharing and homomorphic encryption. We make sure that malicious users are unable to relay software to others. DRM constitutes an incentive for software providers to take part in a future cloud computing scenario.We make this scenario more attractive for users by preserving their privacy. AU - Petrlic, Ronald AU - Sorge, Christoph ID - 588 T2 - Proceedings of the 26th IEEE International Conference on Advanced Information Networking and Applications (AINA) TI - Privacy-Preserving DRM for Cloud Computing ER - TY - CONF AB - We present a privacy-preserving DRM scheme for a (future) cloud computing software market. In such a market, applications are packed into virtual machines (VMs) by software providers and the VMs can be executed at any computing center within the cloud. We propose the introduction of a software TPM as a container for VM-specific keys within the VM that moves around with the VM within the cloud. The software TPM is coupled to a virtual TPM at a computing center to constitute the root of trust for a local DRM enforcement system within the VM that checks the license before each application execution. This allows flexible price models, e.g. execute at most n timeslike models. Users have proof that their personally identifiable information, stored and processed within the VM at a computing center, cannot be obtained by the computing center. A feature of our solution is that neither software provider nor computing center are able to build usage profiles of the software executions. AU - Petrlic, Ronald ID - 589 T2 - Proceedings of the 11th IEEE International Conference on Trust, Security and Privacy in Computing and Communications (TrustCom) TI - Privacy-Preserving Digital Rights Management in a Trusted Cloud Environment ER - TY - CONF AB - Predicate abstraction is an established technique for reducing the size of the state space during verification. In this paper, we extend predication abstraction with block-abstraction memoization (BAM), which exploits the fact that blocks are often executed several times in a program. The verification can thus benefit from caching the values of previous block analyses and reusing them upon next entry into a block. In addition to function bodies, BAM also performs well for nested loops. To further increase effectiveness, block memoization has been integrated with lazy abstraction adopting a lazy strategy for cache refinement. Together, this achieves significant performance increases: our tool (an implementation within the configurable program analysis framework CPAchecker) has won the Competition on Software Verification 2012 in the category “Overall”. AU - Wonisch, Daniel AU - Wehrheim, Heike ID - 590 T2 - Proceedings of the 14th International Conference on Formal Engineering Methods (ICFEM) TI - Predicate Analysis with Block-Abstraction Memoization ER - TY - GEN AU - Celik, Aydin ID - 592 TI - Penny Auctions: Design und Strategisches Verhalten ER - TY - GEN AU - Rojahn, Tobias ID - 593 TI - Optimale Zuteilung von Nutzern zu verteilten Cloud-Standorten ER - TY - GEN AU - Klerx, Timo ID - 594 TI - Online Parameteroptimierung in P2P-Netzwerken mit Hilfe von Neuronalen Netzen ER - TY - GEN AU - Mallmann Trenn, Frederik ID - 595 TI - On scheduling with multi-core and multi-speed processors using power down ER - TY - CONF AB - To meet quality-of-service requirements in changing environments, modern software systems adapt themselves. The structure, and correspondingly the behavior, of these systems undergoes continuous change. Model-driven performance engineering, however, assumes static system structures, behavior, and deployment. Hence, self-adaptive systems pose new challenges to model-driven performance engineering. There are a few surveys on self-adaptive systems, performance engineering, and the combination of both in the literature. In contrast to existing work, here we focus on model-driven performance analysis approaches. Based on a systematic literature review, we present a classication, identify open issues, and outline further research. AU - Becker, Matthias AU - Luckey, Markus AU - Becker, Steffen ID - 596 T2 - Proceedings of the 8th ACM SigSoft International Conference on Quality of Software Architectures (QoSA'12) TI - Model-Driven Performance Engineering of Self-Adaptive Systems: A Survey ER - TY - CONF AB - We consider strategic games in which each player seeks a mixed strategy to minimize her cost evaluated by a concave valuation V (mapping probability distributions to reals); such valuations are used to model risk. In contrast to games with expectation-optimizer players where mixed equilibria always exist [15, 16], a mixed equilibrium for such games, called a V -equilibrium, may fail to exist, even though pure equilibria (if any) transfer over. What is the impact of such valuations on the existence, structure and complexity of mixed equilibria? We address this fundamental question for a particular concave valuation: expectation plus variance, denoted as RA, which stands for risk-averse; so, variance enters as a measure of risk and it is used as an additive adjustment to expectation. We obtain the following results about RA-equilibria:- A collection of general structural properties of RA-equilibria connecting to (i) E-equilibria and Var-equilibria, which correspond to the expectation and variance valuations E and Var, respectively, and to (ii) other weaker or incomparable equilibrium properties.- A second collection of (i) existence, (ii) equivalence and separation (with respect to E-equilibria), and (iii) characterization results for RA-equilibria in the new class of player-specific scheduling games. Using examples, we provide the first demonstration that going from E to RA may as well create new mixed (RA-)equilibria.- A purification technique to transform a player-specific scheduling game on identical links into a player-specific scheduling game so that all non-pure RA-equilibria are eliminated while new pure equilibria cannot be created; so, a particular game on two identical links yields one with no RA-equilibrium. As a by-product, the first-completeness result for the computation of RA-equilibria follows. AU - Mavronicolas, Marios AU - Monien, Burkhard ID - 597 T2 - Proceedings of the 5th International Symposium on Algorithmic Game Theory (SAGT) TI - Minimizing Expectation Plus Variance ER - TY - GEN AU - Mammadov, Fuad ID - 598 TI - Methoden zur Bestimmung von innerbetrieblichen Verrechnungspreisen ER - TY - GEN AU - Löwen, Xenia ID - 599 TI - Managerial Delegation and Capacity Choices: An Analysis of the Cournot-Nash Equilibrium ER - TY - GEN AU - Feldkord, Björn ID - 600 TI - Lokale Swaps und überholte Informationen in Basic Network Creation Games ER - TY - THES AB - Wir betrachten eine Gruppe von mobilen, autonomen Robotern in einem ebenen Gel{\"a}nde. Es gibt keine zentrale Steuerung und die Roboter m{\"u}ssen sich selbst koordinieren. Zentrale Herausforderung dabei ist, dass jeder Roboter nur seine unmittelbare Nachbarschaft sieht und auch nur mit Robotern in seiner unmittelbaren Nachbarschaft kommunizieren kann. Daraus ergeben sich viele algorithmische Fragestellungen. In dieser Arbeit wird untersucht, unter welchen Voraussetzungen die Roboter sich auf einem Punkt versammeln bzw. eine Linie zwischen zwei festen Stationen bilden k{\"o}nnen. Daf{\"u}r werden mehrere Roboter-Strategien in verschiedenen Bewegungsmodellen vorgestellt. Diese Strategien werden auf ihre Effizienz hin untersucht. Es werden obere und untere Schranken f{\"u}r die ben{\"o}tigte Anzahl Runden und die Bewegungsdistanz gezeigt. In einigen F{\"a}llen wird außerdem die ben{\"o}tigte Bewegungsdistanz mit derjenigen Bewegungsdistanz verglichen, die eine optimale globale Strategie auf der gleichen Instanz ben{\"o}tigen w{\"u}rde. So werden kompetititve Faktoren hergeleitet. AU - Kempkes, Barbara ID - 601 SN - 978-3-942647-21-2 TI - Local strategies for robot formation problems VL - 302 ER - TY - GEN AB - We study the consequences of dropping the perfect competition assumption in a standard infinite horizon model with infinitely-lived traders and real collateralized assets, together with one additional ingredient: information among players is asymmetric and monitoring is incomplete. The key insight is that trading assets is not only a way to hedge oneself against uncertainty and to smooth consumption across time: It also enables learning information. Conversely, defaulting now becomes strategic: Certain players may manipulate prices so as to provoke a default in order to prevent their opponents from learning. We focus on learning equilibria, at the end of which no player has incorrect beliefs — not because those players with heterogeneous beliefs were eliminated from the market (although default is possible at equilibrium) but because they have taken time to update their prior belief. We prove a partial Folk theorem à la Wiseman (2011) of the following form: For any function that maps each state of the world to a sequence of feasible and strongly individually rational allocations, and for any degree of precision, there is a perfect Bayesian equilibrium in which patient players learn the realized state with this degree of precision and achieve a payoff close to the one specified for each state. AU - Brangewitz, Sonja ID - 602 TI - Learning by Trading in Infinite Horizon Strategic Market Games with Default ER - TY - GEN AB - Preemptive Routing and Wavelength Assignment (RWA) algorithms preempt established lightpaths in case not enough resources are available to setup a new lightpath in a Wavelength Division Multiplexing (WDM) network. The selection of lightpaths to be preempted relies on internal decisions of the RWA algorithm. Thus, if dedicated properties of the network topology are required by the applications running on the network, these requirements have to be known by the RWA algorithm. Otherwise it might happen that by preempting a particular lightpath these requirements are violated. If, however, these requirements include parameters only known at the nodes running the application, the RWA algorithm cannot evaluate the requirements. For this reason a RWA algorithm is needed which involves its users in the preemption decisions. We present a family of preemptive RWA algorithms for WDM networks. These algorithms have two distinguishing features: a) they can handle dynamic traffic by on-the-fly reconfiguration, and b) users can give feedback for reconfiguration decisions and thus influence the preemption decision of the RWA algorithm, leading to networks which adapt directly to application needs. This is different from traffic engineering where the network is (slowly) adapted to observed traffic patterns. Our algorithms handle various WDM network configurations including networks consisting of heterogeneous WDM hardware. To this end, we are using the layered graph approach together with a newly developed graph model that is used to determine conflicting lightpaths. AU - Wette, Philip AU - Karl, Holger ID - 603 TI - Introducing feedback to preemptive routing and wavelength assignment algorithms for dynamic traffic scenarios ER - TY - GEN AU - Seier, Henrik ID - 604 TI - Implementierung eines Branch-and-Bound-Algorithmus für nichtkonvexe gemischt-ganzzahlige Optimierungsprobleme mit quadratischen Nebenbedingungen ER - TY - GEN AU - Isenberg, Florian ID - 605 TI - Implementierung eines adaptiven Verfahrens zur Linearisierung von nicht-konvexen, nichtlinearen Wassernetzmodellen mit Hilfe einer Fehlerabschätzung ER - TY - JOUR AU - Mehler, Alexander AU - Lücking, Andy AU - Menke, Peter ID - 6055 JF - Neural Networks SN - 0893-6080 TI - Assessing cognitive alignment in different types of dialog by means of a network model VL - 32 ER -