08371 Abstracts Collection -- Fault-Tolerant Distributed Algorithms on VLSI Chips

From September the $7^{text{th}}$, 2008 to September the $10^{text{th}}$, 2008 the Dagstuhl Seminar 08371 ``Fault-Tolerant Distributed Algorithms on VLSI Chips \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. The seminar was devoted to exploring whether the wealth of existing fault-tolerant distributed algorithms research can be utilized for meeting the challenges of future-generation VLSI chips. During the seminar, several participants from both the VLSI and distributed algorithms\u27 discipline, presented their current research, and ongoing work and possibilities for collaboration were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Model Checking a Byzantine-Fault-Tolerant Self-Stabilizing Protocol for Distributed Clock Synchronization Systems

This report presents the mechanical verification of a simplified model of a rapid Byzantine-fault-tolerant self-stabilizing protocol for distributed clock synchronization systems. This protocol does not rely on any assumptions about the initial state of the system. This protocol tolerates bursts of transient failures, and deterministically converges within a time bound that is a linear function of the self-stabilization period. A simplified model of the protocol is verified using the Symbolic Model Verifier (SMV) [SMV]. The system under study consists of 4 nodes, where at most one of the nodes is assumed to be Byzantine faulty. The model checking effort is focused on verifying correctness of the simplified model of the protocol in the presence of a permanent Byzantine fault as well as confirmation of claims of determinism and linear convergence with respect to the self-stabilization period. Although model checking results of the simplified model of the protocol confirm the theoretical predictions, these results do not necessarily confirm that the protocol solves the general case of this problem. Modeling challenges of the protocol and the system are addressed. A number of abstractions are utilized in order to reduce the state space. Also, additional innovative state space reduction techniques are introduced that can be used in future verification efforts applied to this and other protocols

Measurements, Models, Systems and Design

531 s.

Engineering Emergence: A Survey on Control in the World of Complex Networks

Complex networks make an enticing research topic that has been increasingly attracting researchers from control systems and various other domains over the last two decades. The aim of this paper was to survey the interest in control related to complex networks research over time since 2000 and to identify recent trends that may generate new research directions. The survey was performed for Web of Science, Scopus, and IEEEXplore publications related to complex networks. Based on our findings, we raised several questions and highlighted ongoing interests in the control of complex networks.publishedVersio

Third Workshop and Tutorial on Practical Use of Coloured Petri Nets and the CPN Tools, Aarhus, Denmark, August 29-31, 2001

This booklet contains the proceedings of the Third Workshop on Practical Use of Coloured Petri Nets and the CPN Tools, August 29-31, 2001. The workshop is organised by the CPN group at Department of Computer Science, University of Aarhus, Denmark. The papers are also available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop01

A Dual-Mode Adaptive MAC Protocol for Process Control in Industrial Wireless Sensor Networks

Doktorgradsavhandling ved Fakultet for teknologi og realfag, Universitetet i Agder, 2017Wireless Sensor Networks (WSNs) consist of sensors and actuators operating together to provide monitoring and control services. These services are used in versatile applications ranging from environmental monitoring t oindustrial automation applications. Industrial Wireless Sensor Network (IWSN) is a sub domain of the WSN domain, focussing the industrial monitoring and automation applications. The IWSN domain differs from the generic WSN domains in terms of its requirements. General IWSN requirements include: energy efficiency and quality of service, and strict requirements are imposed on the quality of service expected by IWSN applications. Quality of service in particular relates to reliability, robustness, and predictability. Medium Access Control (MAC) protocols in an IWSN solution are responsible for managing radio communications, the main consumer of power in every IWSN element. With proper measures, MAC protocols can provide energy efficient solutions along with required quality of service for process control applications. The first goal of the thesis was to assess the possibility of creating a MAC protocol exploiting properties of the application domain, the process control domain. This resulted in the creation of the Dual-Mode Adaptive Medium Access Control Protocol (DMAMAC) which constitutes the main contribution of this thesis. The DMAMAC protocol is energy efficient,while preserving real-time requirements, and is robust to packet failure. This has been guaranteed by the thorough evaluation of the protocol via simulation, verification, and implementation with deployment testing. In parallel, we also investigated the possibility of using an alternative development approach for MAC protocols. Specifically, we have proposed a development approach based on MAC protocol model in CPN tools. The development approach consists of automatic code generation for the MiXiM simulation tool and the TinyOS platform. We used the related GinMAC protocol as a running example for the development approach. The generated code for MiXiM simulation platform and the TinyOS implementation platform are evaluated via simulation and deployment respectively. This results in a faster design to implementation time, and closely related protocol artifacts, improving on the traditional approach

Symmetry structure in discrete models of biochemical systems : natural subsystems and the weak control hierarchy in a new model of computation driven by interactions

© 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.Interaction Computing (IC) is inspired by the observation that cell metabolic/regulatory systems construct order dynamically, through constrained interactions between their components and based on a wide range of possible inputs and environmental conditions. The goals of this work are (1) to identify and understand mathematically the natural subsystems and hierarchical relations in natural systems enabling this, and (2) to use the resulting insights to define a new model of computation based on interactions that is useful for both biology and computation. The dynamical characteristics of the cellular pathways studied in Systems Biology relate, mathematically, to the computational characteristics of automata derived from them, and their internal symmetry structures to computational power. Finite discrete automata models of biological systems such as the lac operon, Krebs cycle, and p53-mdm2 genetic regulation constructed from Systems Biology models have canonically associated algebraic structures { transformation semigroups. These contain permutation groups (local substructures exhibiting symmetry) that correspond to "pools of reversibility". These natural subsystems are related to one another in a hierarchical manner by the notion of "weak control ". We present natural subsystems arising from several biological examples and their weak control hierarchies in detail. Finite simple non-abelian groups (SNAGs) are found in biological examples and can be harnessed to realize nitary universal computation. This allows ensembles of cells to achieve any desired finitary computational transformation, depending on external inputs, via suitably constrained interactions. Based on this, interaction machines that grow and change their structure recursively are introduced and applied, providing a natural model of computation driven by interactions.Peer reviewe