Schloss Dagstuhl

Displaying 1-40 of 41 results

  • White Papers // Jun 2011

    Extensions of Answer Set Programming

    This paper describes a doctoral research in three areas: Hybrid ASP - an extension of Answer Set Programming for reasoning about dynamical systems, an extension of Set Constraint atoms for reasoning about preferences, computing stable models of logic programs using Metropolis type algorithms. The paper discusses a possible application of...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Correct Reasoning About Logic Programs

    The focus of this paper lies on provably correct static analysis of logic programs, in particular on determinacy inference for logic programs containing cut, and on verified implementations thereof. For reasons which hardly need spelling out here, the question of whether a goal is deterministic or not is central in...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Implementation of Axiomatic Language

    This paper investigates a type of logic programming language called "Axiomatic language". Axiomatic language is intended as a specification language where the user defines the external behavior of a program without giving an algorithm. The language implementation has the task of transforming this input specification into an equivalent efficient algorithm....

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Two Phase Description Logic Reasoning for Efficient Information Retrieval

    Description Logics are used more and more frequently for knowledge representation, creating an increasing demand for efficient automated DL reasoning. However, the existing implementations are inefficient in the presence of large amounts of data. This paper summarizes the results in transforming DL axioms to a set of function-free clauses of...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    A Semiring-Based Framework for Fair Resources Allocation

    In this paper a general framework (based on soft constraints) to model and solve the fair allocation problem is proposed. The authors' formal approach allows to model different allocation problems, ranging from goods and resources allocation to task and chore division. Soft constraints are employed to find a fair solution...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    BAAC: A Prolog System for Action Description and Agents Coordination

    The paper presents a system for knowledge representation and coordination, where autonomous agents reason and act in a shared environment. Agents autonomously pursue individual goals, but can interact through a shared knowledge repository. In the authors' interactions, agents deal with problems of synchronization and concurrency, and have to realize coordination...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    CDAOStore: A Phylogenetic Repository Using Logic Programming and Web Services

    The CDAOStore is a portal aimed at facilitating the storage and retrieval of data and metadata associated to studies in the field of evolutionary biology and phylogenetic analysis. The novelty of CDAOStore lies in the use of a semantic-based approach to the storage and querying of data. This enables CDAOStore...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Bayesian Annotation Networks for Complex Sequence Analysis

    Probabilistic models that associate annotations to sequential data are widely used in computational biology and a range of other applications. Models integrating with logic programs provide, furthermore, for sophistication and generality, at the cost of potentially very high computational complexity. A methodology is proposed for modularization of such models into...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Synthesis of Logic Programs From Object-Oriented Formal Specifications

    Early validation of requirements is crucial for the rigorous development of software. Without it, even the most formal of the methodologies will produce the wrong outcome. One successful approach, popularised by some of the so-called lightweight formal methods, consists in generating (finite, small) models of the specifications. Another possibility is...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Smart Test Data Generators Via Logic Programming

    The authors present a novel counterexample generator for the interactive theorem prover Isabelle based on a compiler that synthesizes test data generators for functional programming languages (e.g., Standard ML, OCaml) from specifications in Isabelle. In contrast to naive type-based test data generators, the smart generators take the preconditions into account...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Multi-Criteria Optimization in Answer Set Programming

    The authors elaborate upon new strategies and heuristics for solving multi-criteria optimization problems via Answer Set Programming (ASP). In particular, they conceive a new solving algorithm, based on conflict-driven learning, allowing for non-uniform descents during optimization. They apply these techniques to solve realistic Linux package configuration problems. To this end,...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Evolution of Ontologies Using ASP

    RDF/S ontologies are often used in e-science to express domain knowledge regarding the respective field of investigation (e.g., cultural informatics, bioinformatics etc). Such ontologies need to change often to reflect the latest scientific understanding on the domain at hand, and are usually associated with constraints expressed using various declarative formalisms...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Static Type Checking for the Q Functional Language in Prolog

    The authors describe an application of Prolog: a type checking tool for the Q functional language. Q is a terse vector processing language, a descendant of APL, which is getting more and more popular, especially in financial applications. Q is a dynamically typed language, much like Prolog. Extending Q with...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Compiling Prolog to Idiomatic Java

    Today, Prolog is often used to solve well-defined, domain-specific problems that are part of larger applications. In such cases, a tight integration of the Prolog program and the rest of the application, which is commonly written in a different language, is necessary. One common approach is to compile the Prolog...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    The Scope of the IBGP Routing Anomaly Problem

    Correctness problems in the iBGP routing, the de-facto standard to spread global routing information in Autonomous Systems, are a well-known issue. Configurations may route cost-suboptimal, inconsistent, or even behave non-convergent and -deterministic. However, even if a lot of studies have shown many exemplary problematic configurations, the exact scope of the...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Anonymous Communication in the Digital World

    Privacy on the Internet is becoming a concern as an already significant and ever growing part of the daily activities is carried out online. While cryptography can be used to protect the integrity and confidentiality of contents of communication, everyone along the route on which a packet is traveling can...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Does Proactive Secret Sharing Perform in Peer-to-Peer Systems?

    Trustworthy applications in fully decentralized systems require a trust anchor. This paper describes how such an anchor can be implemented efficiently in p2p systems. The basic concept is to use threshold cryptography in order to sign messages by a quorum of peers. The focus is put on advanced mechanisms to...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Reputation-Based Approach to Self-Adaptive Service Selection

    Service-orientation provides concepts and tools for flexible composition and management of large-scale distributed software applications. The automated run-time management of such loosely coupled software systems, however, poses still major challenges and is therefore an active research area, including the use of novel computing paradigms. In this context, the dynamic and...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Service-Oriented Operating System and an Application Development Infrastructure for Distributed Embedded Systems

    The paradigm of service-orientation promises a significant ease of use in creating and managing distributed software systems. A very important aspect here is that also application domain experts and stakeholders, who are not necessarily skilled in computer programming, get a chance to create, analyze, and adapt distributed applications. However, up...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    An Adaptive Protocol for Distributed Beamforming

    The authors study distributed adaptive beamforming in networks of wireless nodes. In particular, they observe that for the synchronisation of carrier phases, distinct algorithmic configurations are optimal in various environmental settings and propose a protocol that utilises organic computing principles to find optimum parameters. Furthermore, they study the impact of...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Web Workload Generation According to the UniLoG Approach

    Generating synthetic loads which are sufficiently close to reality represents an important and challenging task in performance and Quality-of-Service (QoS) evaluations of computer networks and distributed systems. Here, the load to be generated represents sequences of requests at a well-defined service interface within a network node. The paper presents a...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Improving Markov-Based TCP Traffic Classification

    This paper presents an improved variant of the authors' Markov-based TCP traffic classifier and demonstrates its performance using traffic captured in a university network. Payload length, flow direction, and position of the first data packets of a TCP connection are reflected in the states of the Markov models. In addition,...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    TOGBAD-LQ - Using Challenge-Response to Detect Fake Link Qualities

    The usage of link quality based routing metrics significantly improves the quality of the chosen paths and by that the performance of the network. But, attackers may try to exploit link qualities for their purposes. Especially in tactical multi-hop networks, routing may fall prey to an attacker. Such routing attacks...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    IT Management Using a Heavyweight CIM Ontology

    This paper presents an approach for ontology-based IT management based on a heavyweight (formal) ontology using the Web Ontology Language (OWL). The ontology comprises a complete OWL representation of the Common Information Model (CIM) and management rules defined in the Semantic Web Rule Language (SWRL). The ontology not only models...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Avoiding Publication and Privatization Problems on Software Transactional Memory

    This paper presents a new approach to exclude problems arising from dynamically switching between protected concurrent and unprotected single-threaded use of shared data when using software transactional memory in OO languages such as Java. The approach is based on a simple but effective programming model separating transactions from non-transactional operation....

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Resilient and Energy-Saving Incentive System for Resource Sharing in MANETs

    Despite of all progress in terms of computational power, communication bandwidth, and feature richness, limited battery capacity is the major bottleneck for using the resources of mobile devices in innovative distributed applications. Incentives are required for motivating a user to spend energy on behalf of other users and it must...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Supporting Cooperative Traffic Information Systems Through Street-Graph-Based Peer-to-Peer Networks

    In this paper, the authors present a novel peer-to-peer system specifically designed to support the unique properties of traffic information systems. They discuss important design decisions, such as update strategies and algorithms for dynamic vehicular route planning. The system is then assessed using a combination of network (OverSim/OMNeT++) and road...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Distributed Probabilistic Network Traffic Measurements

    Measuring the per-flow traffic in large networks is very challenging due to the high performance requirements on the one hand, and due to the necessity to merge locally recorded data from multiple routers in order to obtain network-wide statistics on the other hand. The latter is nontrivial because traffic that...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Privacy-Preserving Social P2P Infrastructure for People-Centric Sensing

    The rapid miniaturization and integration of sensor technologies into mobile Internet devices combined with Online Social Networks allows for enhanced sensor information querying, subscription, and task placement within People-Centric Sensing networks. However, PCS systems which exploit knowledge about OSN user profiles and context information for enhanced service provision might cause...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Optimization-Based Secure Multi-Hop Localization in Wireless Ad Hoc Networks

    The problem of localizing nodes without GPS based on a small fraction of anchor nodes which are aware of their positions is considered to be an important service for applications in wireless ad hoc networks. With an adversary trying to mislead nodes about their estimated locations, several approaches aiming to...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Efficient Distributed Intrusion Detection Applying Multi Step Signatures

    Intrusion Detection Systems (IDS) offer valuable measures to cope with today's attacks on computers and networks. But the increasing performance of networks and end systems and the growing complexity of IT systems lead to rapidly growing volumes of observation data and large signature bases. Therefore, IDS are forced to drop...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Node Degree Based Improved Hop Count Weighted Centroid Localization Algorithm

    Hop-count based weighted centroid localization is a simple and straightforward localization algorithm, which uses anchors with known positions and the hop count to these anchors to estimate the real position of nodes. Especially in sensor networks, where energy restrictions prevent more complex algorithms, this fast and simple algorithm can be...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Browser as a Service (BaaS): Security and Performance Enhancements for the Rich Web

    This paper introduces an architectural approach to access the Web via a virtual Web browser executed within a secure Cloud environment. The Web has become an indispensable prerequisite of everyday live and the Web browser is the most used application on a variety of distinct devices. The content delivered by...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Model Driven Development of Distributed Business Applications

    The present paper presents a model driven generative approach to the design and implementation of distributed business applications, which consequently and systematically implements many years of MDSD experience for the software engineering of large application development projects in an industrial context. MDSD (Model-Driven Software Development) is a generic term covering...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Optimized DTN-Routing for Urban Public Transport Systems

    Communication is crucial to the coordination and efficient operation of public transport systems. However, deployment of infrastructure based communication systems is expensive, esp. due to long-term operational costs. Delay tolerant vehicular networks are a promising alternative since only very few infrastructure elements are required. This paper presents a DTN routing...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Survey of Information-Centric Networking

    The development of the Information-Centric Networking (ICN) concept is one of the significant results of different international Future Internet research activities. In this concept, the principal paradigm is not end-to-end communication between hosts - as in the current Internet architecture. Instead, an increasing demand for highly scalable and efficient distribution...

    Provided By Schloss Dagstuhl

  • White Papers // Dec 2010

    Model Checking Concurrent Programs With Nondeterminism and Randomization

    The use of randomization in concurrent or distributed systems is often key to achieving certain objectives - it is used in distributed algorithms to break symmetry and in cryptographic protocols to achieve semantic security. The formal analysis of such systems has often modelled them as Markov Decision Processes, that has...

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    Model Checking Time-Constrained Scenario-Based Specifications

    The authors consider the problem of model checking message-passing systems with real-time requirements. As behavioural specifications, they use Message Sequence Charts (MSCs) annotated with timing constraints. Their system model is a network of communicating finite state machines with local clocks, whose global behaviour can be regarded as a timed automaton....

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    The Complexity of Model Checking (Collapsible) Higher-Order Pushdown Systems

    The authors study (collapsible) higher-order pushdown systems - theoretically robust and well-studied models of higher-order programs - along with their natural subclass called (collapsible) higher-order basic process algebras. They provide a comprehensive analysis of the model checking complexity of a range of both branching-time and linear-time temporal logics. They obtain...

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    Two Size Measures for Timed Languages

    Quantitative properties of timed regular languages, such as information content (growth rate, entropy) are explored. The approach suggested by the same authors is extended to languages of timed automata with punctual (equalities) and non-punctual (non-equalities) transition guards. Two size measures for such languages are identified: mean dimension and volumetric entropy....

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Survey of Information-Centric Networking

    The development of the Information-Centric Networking (ICN) concept is one of the significant results of different international Future Internet research activities. In this concept, the principal paradigm is not end-to-end communication between hosts - as in the current Internet architecture. Instead, an increasing demand for highly scalable and efficient distribution...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Multi-Criteria Optimization in Answer Set Programming

    The authors elaborate upon new strategies and heuristics for solving multi-criteria optimization problems via Answer Set Programming (ASP). In particular, they conceive a new solving algorithm, based on conflict-driven learning, allowing for non-uniform descents during optimization. They apply these techniques to solve realistic Linux package configuration problems. To this end,...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Evolution of Ontologies Using ASP

    RDF/S ontologies are often used in e-science to express domain knowledge regarding the respective field of investigation (e.g., cultural informatics, bioinformatics etc). Such ontologies need to change often to reflect the latest scientific understanding on the domain at hand, and are usually associated with constraints expressed using various declarative formalisms...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Static Type Checking for the Q Functional Language in Prolog

    The authors describe an application of Prolog: a type checking tool for the Q functional language. Q is a terse vector processing language, a descendant of APL, which is getting more and more popular, especially in financial applications. Q is a dynamically typed language, much like Prolog. Extending Q with...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Compiling Prolog to Idiomatic Java

    Today, Prolog is often used to solve well-defined, domain-specific problems that are part of larger applications. In such cases, a tight integration of the Prolog program and the rest of the application, which is commonly written in a different language, is necessary. One common approach is to compile the Prolog...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Synthesis of Logic Programs From Object-Oriented Formal Specifications

    Early validation of requirements is crucial for the rigorous development of software. Without it, even the most formal of the methodologies will produce the wrong outcome. One successful approach, popularised by some of the so-called lightweight formal methods, consists in generating (finite, small) models of the specifications. Another possibility is...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Smart Test Data Generators Via Logic Programming

    The authors present a novel counterexample generator for the interactive theorem prover Isabelle based on a compiler that synthesizes test data generators for functional programming languages (e.g., Standard ML, OCaml) from specifications in Isabelle. In contrast to naive type-based test data generators, the smart generators take the preconditions into account...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    BAAC: A Prolog System for Action Description and Agents Coordination

    The paper presents a system for knowledge representation and coordination, where autonomous agents reason and act in a shared environment. Agents autonomously pursue individual goals, but can interact through a shared knowledge repository. In the authors' interactions, agents deal with problems of synchronization and concurrency, and have to realize coordination...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    CDAOStore: A Phylogenetic Repository Using Logic Programming and Web Services

    The CDAOStore is a portal aimed at facilitating the storage and retrieval of data and metadata associated to studies in the field of evolutionary biology and phylogenetic analysis. The novelty of CDAOStore lies in the use of a semantic-based approach to the storage and querying of data. This enables CDAOStore...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Bayesian Annotation Networks for Complex Sequence Analysis

    Probabilistic models that associate annotations to sequential data are widely used in computational biology and a range of other applications. Models integrating with logic programs provide, furthermore, for sophistication and generality, at the cost of potentially very high computational complexity. A methodology is proposed for modularization of such models into...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Extensions of Answer Set Programming

    This paper describes a doctoral research in three areas: Hybrid ASP - an extension of Answer Set Programming for reasoning about dynamical systems, an extension of Set Constraint atoms for reasoning about preferences, computing stable models of logic programs using Metropolis type algorithms. The paper discusses a possible application of...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    A Semiring-Based Framework for Fair Resources Allocation

    In this paper a general framework (based on soft constraints) to model and solve the fair allocation problem is proposed. The authors' formal approach allows to model different allocation problems, ranging from goods and resources allocation to task and chore division. Soft constraints are employed to find a fair solution...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Correct Reasoning About Logic Programs

    The focus of this paper lies on provably correct static analysis of logic programs, in particular on determinacy inference for logic programs containing cut, and on verified implementations thereof. For reasons which hardly need spelling out here, the question of whether a goal is deterministic or not is central in...

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Implementation of Axiomatic Language

    This paper investigates a type of logic programming language called "Axiomatic language". Axiomatic language is intended as a specification language where the user defines the external behavior of a program without giving an algorithm. The language implementation has the task of transforming this input specification into an equivalent efficient algorithm....

    Provided By Schloss Dagstuhl

  • White Papers // Jun 2011

    Two Phase Description Logic Reasoning for Efficient Information Retrieval

    Description Logics are used more and more frequently for knowledge representation, creating an increasing demand for efficient automated DL reasoning. However, the existing implementations are inefficient in the presence of large amounts of data. This paper summarizes the results in transforming DL axioms to a set of function-free clauses of...

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    Model Checking Time-Constrained Scenario-Based Specifications

    The authors consider the problem of model checking message-passing systems with real-time requirements. As behavioural specifications, they use Message Sequence Charts (MSCs) annotated with timing constraints. Their system model is a network of communicating finite state machines with local clocks, whose global behaviour can be regarded as a timed automaton....

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    The Complexity of Model Checking (Collapsible) Higher-Order Pushdown Systems

    The authors study (collapsible) higher-order pushdown systems - theoretically robust and well-studied models of higher-order programs - along with their natural subclass called (collapsible) higher-order basic process algebras. They provide a comprehensive analysis of the model checking complexity of a range of both branching-time and linear-time temporal logics. They obtain...

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    Two Size Measures for Timed Languages

    Quantitative properties of timed regular languages, such as information content (growth rate, entropy) are explored. The approach suggested by the same authors is extended to languages of timed automata with punctual (equalities) and non-punctual (non-equalities) transition guards. Two size measures for such languages are identified: mean dimension and volumetric entropy....

    Provided By Schloss Dagstuhl

  • White Papers // Dec 2010

    Model Checking Concurrent Programs With Nondeterminism and Randomization

    The use of randomization in concurrent or distributed systems is often key to achieving certain objectives - it is used in distributed algorithms to break symmetry and in cryptographic protocols to achieve semantic security. The formal analysis of such systems has often modelled them as Markov Decision Processes, that has...

    Provided By Schloss Dagstuhl

  • White Papers // Oct 2010

    Verifying Recursive Active Documents With Positive Data Tree Rewriting

    This paper considers a tree-rewriting framework for modeling documents evolving through service calls. The authors focus on the automatic verification of properties of documents that may contain data from an infinite domain. Their establish the boundaries of decidability: while verifying documents with recursive calls is undecidable, they obtain decidability as...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    The Scope of the IBGP Routing Anomaly Problem

    Correctness problems in the iBGP routing, the de-facto standard to spread global routing information in Autonomous Systems, are a well-known issue. Configurations may route cost-suboptimal, inconsistent, or even behave non-convergent and -deterministic. However, even if a lot of studies have shown many exemplary problematic configurations, the exact scope of the...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Reputation-Based Approach to Self-Adaptive Service Selection

    Service-orientation provides concepts and tools for flexible composition and management of large-scale distributed software applications. The automated run-time management of such loosely coupled software systems, however, poses still major challenges and is therefore an active research area, including the use of novel computing paradigms. In this context, the dynamic and...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Service-Oriented Operating System and an Application Development Infrastructure for Distributed Embedded Systems

    The paradigm of service-orientation promises a significant ease of use in creating and managing distributed software systems. A very important aspect here is that also application domain experts and stakeholders, who are not necessarily skilled in computer programming, get a chance to create, analyze, and adapt distributed applications. However, up...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    An Adaptive Protocol for Distributed Beamforming

    The authors study distributed adaptive beamforming in networks of wireless nodes. In particular, they observe that for the synchronisation of carrier phases, distinct algorithmic configurations are optimal in various environmental settings and propose a protocol that utilises organic computing principles to find optimum parameters. Furthermore, they study the impact of...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Web Workload Generation According to the UniLoG Approach

    Generating synthetic loads which are sufficiently close to reality represents an important and challenging task in performance and Quality-of-Service (QoS) evaluations of computer networks and distributed systems. Here, the load to be generated represents sequences of requests at a well-defined service interface within a network node. The paper presents a...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Improving Markov-Based TCP Traffic Classification

    This paper presents an improved variant of the authors' Markov-based TCP traffic classifier and demonstrates its performance using traffic captured in a university network. Payload length, flow direction, and position of the first data packets of a TCP connection are reflected in the states of the Markov models. In addition,...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    TOGBAD-LQ - Using Challenge-Response to Detect Fake Link Qualities

    The usage of link quality based routing metrics significantly improves the quality of the chosen paths and by that the performance of the network. But, attackers may try to exploit link qualities for their purposes. Especially in tactical multi-hop networks, routing may fall prey to an attacker. Such routing attacks...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    IT Management Using a Heavyweight CIM Ontology

    This paper presents an approach for ontology-based IT management based on a heavyweight (formal) ontology using the Web Ontology Language (OWL). The ontology comprises a complete OWL representation of the Common Information Model (CIM) and management rules defined in the Semantic Web Rule Language (SWRL). The ontology not only models...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Avoiding Publication and Privatization Problems on Software Transactional Memory

    This paper presents a new approach to exclude problems arising from dynamically switching between protected concurrent and unprotected single-threaded use of shared data when using software transactional memory in OO languages such as Java. The approach is based on a simple but effective programming model separating transactions from non-transactional operation....

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Resilient and Energy-Saving Incentive System for Resource Sharing in MANETs

    Despite of all progress in terms of computational power, communication bandwidth, and feature richness, limited battery capacity is the major bottleneck for using the resources of mobile devices in innovative distributed applications. Incentives are required for motivating a user to spend energy on behalf of other users and it must...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Supporting Cooperative Traffic Information Systems Through Street-Graph-Based Peer-to-Peer Networks

    In this paper, the authors present a novel peer-to-peer system specifically designed to support the unique properties of traffic information systems. They discuss important design decisions, such as update strategies and algorithms for dynamic vehicular route planning. The system is then assessed using a combination of network (OverSim/OMNeT++) and road...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Distributed Probabilistic Network Traffic Measurements

    Measuring the per-flow traffic in large networks is very challenging due to the high performance requirements on the one hand, and due to the necessity to merge locally recorded data from multiple routers in order to obtain network-wide statistics on the other hand. The latter is nontrivial because traffic that...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    A Privacy-Preserving Social P2P Infrastructure for People-Centric Sensing

    The rapid miniaturization and integration of sensor technologies into mobile Internet devices combined with Online Social Networks allows for enhanced sensor information querying, subscription, and task placement within People-Centric Sensing networks. However, PCS systems which exploit knowledge about OSN user profiles and context information for enhanced service provision might cause...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Optimization-Based Secure Multi-Hop Localization in Wireless Ad Hoc Networks

    The problem of localizing nodes without GPS based on a small fraction of anchor nodes which are aware of their positions is considered to be an important service for applications in wireless ad hoc networks. With an adversary trying to mislead nodes about their estimated locations, several approaches aiming to...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Efficient Distributed Intrusion Detection Applying Multi Step Signatures

    Intrusion Detection Systems (IDS) offer valuable measures to cope with today's attacks on computers and networks. But the increasing performance of networks and end systems and the growing complexity of IT systems lead to rapidly growing volumes of observation data and large signature bases. Therefore, IDS are forced to drop...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Node Degree Based Improved Hop Count Weighted Centroid Localization Algorithm

    Hop-count based weighted centroid localization is a simple and straightforward localization algorithm, which uses anchors with known positions and the hop count to these anchors to estimate the real position of nodes. Especially in sensor networks, where energy restrictions prevent more complex algorithms, this fast and simple algorithm can be...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Browser as a Service (BaaS): Security and Performance Enhancements for the Rich Web

    This paper introduces an architectural approach to access the Web via a virtual Web browser executed within a secure Cloud environment. The Web has become an indispensable prerequisite of everyday live and the Web browser is the most used application on a variety of distinct devices. The content delivered by...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Model Driven Development of Distributed Business Applications

    The present paper presents a model driven generative approach to the design and implementation of distributed business applications, which consequently and systematically implements many years of MDSD experience for the software engineering of large application development projects in an industrial context. MDSD (Model-Driven Software Development) is a generic term covering...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Anonymous Communication in the Digital World

    Privacy on the Internet is becoming a concern as an already significant and ever growing part of the daily activities is carried out online. While cryptography can be used to protect the integrity and confidentiality of contents of communication, everyone along the route on which a packet is traveling can...

    Provided By Schloss Dagstuhl

  • White Papers // Feb 2011

    Optimized DTN-Routing for Urban Public Transport Systems

    Communication is crucial to the coordination and efficient operation of public transport systems. However, deployment of infrastructure based communication systems is expensive, esp. due to long-term operational costs. Delay tolerant vehicular networks are a promising alternative since only very few infrastructure elements are required. This paper presents a DTN routing...

    Provided By Schloss Dagstuhl