175 research outputs found

    Eighth Workshop and Tutorial on Practical Use of Coloured Petri Nets and the CPN Tools, Aarhus, Denmark, October 22-24, 2007

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    This booklet contains the proceedings of the Eighth Workshop on Practical Use of Coloured Petri Nets and the CPN Tools, October 22-24, 2007. The workshop is organised by the CPN group at the 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/workshop0

    Modeling and verification of web service composition based interorganizational workflows

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    Interorganisationale Workflows sind Arbeitsabläufe, welche die Grenzen einer Organisation verlassen und einen Rahmen für Kooperationen der verschiedenen autonomen Organisationen zur Verfügung stellen. Ein wichtiger Punkt für den Entwurf solcher Workflows ist die Balance zwischen Offenheit und Abgrenzung, wobei erstere für Kooperationen und letztere die für den Schutz von Know-how benötigt wird. Workflow Sichten stellen ein effizientes Werkzeug für diesen Zweck zur Verfügung. Durch Offenlegung von bestimmten Teilen eines Prozesses, können Organisationen sowohl kooperieren als auch das Know-how schützen. Diese Dissertation präsentiert nun eine Methode für die korrekte Konstruktion von Workflow Sichten. Es wird angenommen, dass Organisationen Web Service orientierte Technologien zur Modellierung und Implementierung von interorganisationalen Workflows verwenden. Die Anwendung von Web Services bietet Organisationen viele Vorteile. Den eigentlichen Mehrwert von Web Services stellt aber die Kompositionsfähigkeit dar. Verfügbare Web Services können dadurch von anderen Choreographien und Orchestrationen (wieder-)verwendet werden. Die Notwendigkeit der Implementierung von Systemen von Null weg kann minimiert werden. Die zentralen Anforderungen sind einerseits eine Architektur mit adäquatem Potential, andererseits die Verifikation der Korrektheit. Diese Dissertation präsentiert nun eine Architektur zur Modellierung von Web Service Composition basierten interorganisationalen Workflows, genannt föderierte Choreographien, die verglichen mit anderen Architekturen verschiedene Vorteile anbieten. Darüber hinaus werden Algorithmen und Techniken zur Verifikation der strukturellen und temporalen Korrektheit vorgestellt. Strukturelle Korrektheit prüft, ob die Strukturen der beteiligten Prozesse zusammenpassen. Temporale Korrektheit überprüft, ob ein interorganisationaler Workflow, der aus mehreren Choreographien und Orchestrationen besteht hinsichtlich der lokalen und globalen Bedingungen fehlerfrei ist. Mit Hilfe dieser Techniken kann die strukturelle und temporale Konformität des Modells zur Designzeit überprüft werden. Falls das Modell nicht strukturell oder temporal konform ist, können nötige Änderungen durchgeführt werden, sodass die korrekte Ausführung zur Laufzeit garantiert werden kann. Die Überprüfung der Konformität zur Designzeit reduziert die Prozesskosten vor allem wegen den folgenden zwei Gründen: Erstens, die entdeckten Fehler zur Designzeit sind normalerweise billiger als jene, die zur Laufzeit entdeckt werden und zweitens, Fehlerbehandlungsmechanismen können verhindert werden, die wiederum Zusatzkosten verursachen. Zusätzlich zu der vorgestellten Architektur wird eine allgemeinere Architektur zusammen mit den passenden Konformitätsprüfungsalgorithmen präsentiert. Der Ansatz ist Platform- und sprachunabhängig und die Algorithmen sind verteilt.Interorganizational workflows are workflows that cross the boundaries of a single organization and provide a framework for cooperation of different autonomous organizations. An important issue when designing such workflows is the balance between the openness needed for cooperation and the privacy needed for protection of business know-how. Workflow views provide an efficient tool for this aim. By exposure of only selected parts of a process, organizations can both cooperate and protect their business logic. This dissertation presents a technique for a correct construction of workflow views. It is assumed that organizations and partners use web services and web service related technology to model and implement interorganizational workflows. Application of web services offers several advantages for organizations. The real surplus of web services is their capability of being composed to more complex systems. Available web services can be reused by other choreographies and orchestrations and the need for development of new systems from scratch can be minimized. The essential requirements are on the one hand an architecture with adequate capabilities and on the other hand, verification of correctness. This dissertation proposes an architecture for modeling web service composition based interorganizational workflows, called \emph{federated choreographies}, that provides several advantages compared to existing proposals. Moreover, algorithms and techniques for verification of structural and temporal correctness of interorganizational workflows are proposed. Structural conformance checks if the structures of the involved processes match. Temporal conformance checks if an interorganizational workflow composed of choreographies and orchestrations is temporally error-free with respect to local and global temporal constraints. The proposed algorithms can be applied for checking the structural and temporal conformance of the federated choreographies at design-time. If the model is not structurally or temporally conformant, necessary modifications can be done such that the correct execution of the flow at run-time can be guaranteed. The conformance checking at design time reduces the cost of process because of two reasons: first, errors detected at design time are normally cheaper than those detected at run time and second, exception handling mechanisms can be avoided which are, in turn, coupled with additional costs. In addition to the proposed architecture, a more general architecture together with the conformance checking algorithms and techniques for interorganizational workflows are presented. The presented approach is language and platform independent and algorithms work in a distributed manner

    Modelling Contracts and Workflows for Verification and Enactment

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    The work presented in this thesis concerns some aspects related to the Modelling of Contracts and Workflows for Verification and Enactment. We have sought to gain some insight into the nature of contracts and workflows. in order that we may model them. primarily, for the purposes of verifying certain properties and for enacting them. Workflows help coordinate the enactment of business processes. A notable aspect of workflow technologies is the lack of formal semantics for workflow models. In this thesis, we consider the characterisation of workflow using a number of formal tools, viz. Milner's CCS, Cleaveland et ai's Prioritised CCS (which we abbreviate to PCCS) and the Situation Calculus (thanks mainly to Reiter), which is based on First-Order Logic. Using these, we provide formalisations of production workflows, which are somewhat rigid, inflexible structures, akin to production lines. We do so, in order that we may fiJo: their operational meaning for the purposes of verification and enactment. We define the Liesbet meta-model for production workflow to provide a reference ontology for the task of formalisation. We have also implemented a framework for the verification and enactment of Liesbet workflow models. Regarding verification, we are particularly interested in the key property of soundness, which is concerned with an absence of locking and redundant tasks in a workflow model. Our framework is capable of verifying this property of workflow models, as well as arbitrary temporally-extended constraints', which are constraints whose satisfaction is determined over successive states of enactment of a model. We also consider the definition of more flexible workflows, including collaborative workflows, using an approach that we have conceived called Institutional Workflow Modelling (IWM). The essence of IWM lies (in part) in the identification that the structure of a workflow model necessarily entails the existence of counts as relations. These relations prescribe how the occurrence of certain actions, in the context of a particular workflow model. count as the occurrence of other actions. We have also been interested in the modelling of contracts; and have found IWM to be useful as a foundational basis for contract modelling. ????????? Another fu.ndamental aspect of our IWM-based approach is a correspondence, which we have identified, between counts as relations and methods in Hierarchical Task Network (HTN)-based planning. Thus, we are able to advocate the use of an HTN-based planning framework for the verification of flexible workflows and contracts. We have implemented such a framework, whose planner is called Theodore. We define a sjmilar notion of soundness for flexible workflows and contracts, which the Theodore-based framework is able to verify, along with arbitrary temporallyextended constraints.Imperial Users onl

    Management of Data and Collaboration for Business Processes

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    A business process (BP) is a collection of activities and services assembled together to accomplish a business goal. Business process management (BPM) refers to the man- agement and support for a collection of inter-related business processes, which has been playing an essential role in all enterprises. Business practitioners today face enormous difficulties in managing data for BPs due to the fact that the data for BP execution is scattered across databases for enterprise, auxiliary data stores managed by the BPM sys- tems, and even file systems (e.g., definition of BP models). Moreover, current data and business process modeling approaches leave associations of persistent data in databases and data in BPs to the implementation level with little abstraction. Implementing busi- ness logic involves data access from and to database often demands high development efforts.In the current study, we conceptualize the data used in BPs by capturing all needed information for a BP throughout its execution into a “universal artifact”. The concep- tualization provides a foundation for the separation of BP execution and BP data. With the new framework, the data analysis can be carried out without knowing the logic of BPs and the modification of the BP logics can be directly applied without understanding the data structure.Even though universal artifacts provide convenient data access for processes, the data is yet stored in the underlying database and the relationship between data in artifacts and the one in database is still undefined. In general, a way to link the data of these two data sources is needed. we propose a data mapping language aiming to bridge BP data and enterprise database, so that the BP designers only need to focus on business data instead of how to manipulate data by accessing the database. We formulate syntactic conditions upon specified mapping in order that updates upon database or BP data can be properly propagated.In database area, mapping database to a view has been widely studied In recently years, data exchange method extends the notion of database views to a target database (i.e., multiple views) by using a set of conjunctive queries called “tuple generating de- pendency” (tgd). Tgd is a language that is easy to understand/specify, expressive, and decidable for a wide range of properties, which is ideal as a mapping language. Naturally, if both enterprise database and artifacts are represented as relational database, we can take advantage of data exchange technology to bridge enterprise database and artifacts by using tgd as well. Therefore, we re-visit the mapping and update propagation problem under the relational setting.In addition to the data management for a single BP, it is equivalently essential to un- derstand how messages and data should be exchanged among multiple collaborative BPs. With the introduction of artifacts, data is explicitly modeled that can be used in a collab- orative setting. Unfortunately, today’s BP collaboration languages (either orchestration or choreography) do not emphasize on how data is evolved during execution. More- over, the existing languages always assume each participant type has a single participant instance. Therefore, a declarative language is introduced to specify the collaboration among BPs with data and multiple instances concerned. The language adopts a subset of linear temporal logics (LTL) as constraints to restrict the behavior of the collaborative BPs.As a follow-up study, we focus on the satisfiability problem of the declarative BP collaboration language, i.e., whether a given specification as a set of constraints allows at least one finite execution. Naturally, if a specification excludes every possible execution, it should be considered as an undesirable design. Therefore, we consider different combi- nation of the constraint types and for each combination, syntactic conditions are provided to decide whether the given constraints are satisfiable. The syntactic conditions automat- ically lead to polynomial testing methods (comparing to PSPACE-complete complexity of general LTL satisfiability testing)

    A Survey on Security and Privacy of 5G Technologies: Potential Solutions, Recent Advancements, and Future Directions

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    Security has become the primary concern in many telecommunications industries today as risks can have high consequences. Especially, as the core and enable technologies will be associated with 5G network, the confidential information will move at all layers in future wireless systems. Several incidents revealed that the hazard encountered by an infected wireless network, not only affects the security and privacy concerns, but also impedes the complex dynamics of the communications ecosystem. Consequently, the complexity and strength of security attacks have increased in the recent past making the detection or prevention of sabotage a global challenge. From the security and privacy perspectives, this paper presents a comprehensive detail on the core and enabling technologies, which are used to build the 5G security model; network softwarization security, PHY (Physical) layer security and 5G privacy concerns, among others. Additionally, the paper includes discussion on security monitoring and management of 5G networks. This paper also evaluates the related security measures and standards of core 5G technologies by resorting to different standardization bodies and provide a brief overview of 5G standardization security forces. Furthermore, the key projects of international significance, in line with the security concerns of 5G and beyond are also presented. Finally, a future directions and open challenges section has included to encourage future research.European CommissionNational Research Tomsk Polytechnic UniversityUpdate citation details during checkdate report - A

    Heavy meta: model-driven domain-specific generation of generative domain-specific modeling tools

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    Software is so prevalent in all areas of life that one could expect we have come up with more simple and intuitive ways for its creation by now. However, software development is still too complicated to easily and efficiently cope with individual demands, customizations, and changes. Model-based approaches promise improvements through a more comprehensible layer of abstraction, but they are rarely fully embraced in practice. They are perceived as being overly complex, imposing additional work, and lacking the flexibility required in the real world. This thesis presents a novel approach to model-driven software engineering that focuses on simplicity through highly specialized tools. Domain experts are provided with development tools tailored to their individual needs, where they can easily specify the intent of the software using their known terms and concepts. This domain specificity (D) is a powerful mechanism to boil down the effort of defining a system to relevant aspects only. Many concepts are set upfront, which imposes a huge potential for automated generation. However, the full potential of domain-specific models can only unfold, if they are used as primary artifacts of development. The presented approach thus combines domain specificity with full generation (F) to achieve an overall pushbutton generation that does not require any round-trip engineering. Furthermore, service orientation (S) introduces a ‘just use’ philosophy of including arbitrarily complex functionality without needing to know their implementation, which also restores flexibility potentially sacrificed by the domain focus. The unique combination of these three DFS properties facilitates a focused, efficient, and flexible simplicity-driven way of software development. Key to the approach is a holistic solution that in particular also covers the simplicity-driven development of the required highly specialized DFS tools, as nothing would be gained if the costs of developing such tools outweighed the resulting benefits. This simplicity is achieved by applying the very same DFS concepts to the domain of tool development itself: DFS modeling tools are fully generated from models and services specialized to the (meta) domain of modeling tools. The presented Cinco meta tooling suite is a first implementation of such a meta DFS tool. It focuses on the generation of graphical modeling tools for graph structures comprising of various types of nodes and edges. Cinco has been very successfully applied to numerous industrial and academic projects, and thus also serves as a proof of concept for the DFS approach itself. The unique combination of the three DFS strategies and Cinco's meta-level approach towards their realization in practice lay the foundation for a new paradigm of software development that is strongly focused on simplicity

    Challenges in Cybersecurity and Privacy - the European Research Landscape

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    Cybersecurity and Privacy issues are becoming an important barrier for a trusted and dependable global digital society development. Cyber-criminals are continuously shifting their cyber-attacks specially against cyber-physical systems and IoT, since they present additional vulnerabilities due to their constrained capabilities, their unattended nature and the usage of potential untrustworthiness components. Likewise, identity-theft, fraud, personal data leakages, and other related cyber-crimes are continuously evolving, causing important damages and privacy problems for European citizens in both virtual and physical scenarios. In this context, new holistic approaches, methodologies, techniques and tools are needed to cope with those issues, and mitigate cyberattacks, by employing novel cyber-situational awareness frameworks, risk analysis and modeling, threat intelligent systems, cyber-threat information sharing methods, advanced big-data analysis techniques as well as exploiting the benefits from latest technologies such as SDN/NFV and Cloud systems. In addition, novel privacy-preserving techniques, and crypto-privacy mechanisms, identity and eID management systems, trust services, and recommendations are needed to protect citizens’ privacy while keeping usability levels. The European Commission is addressing the challenge through different means, including the Horizon 2020 Research and Innovation program, thereby financing innovative projects that can cope with the increasing cyberthreat landscape. This book introduces several cybersecurity and privacy research challenges and how they are being addressed in the scope of 15 European research projects. Each chapter is dedicated to a different funded European Research project, which aims to cope with digital security and privacy aspects, risks, threats and cybersecurity issues from a different perspective. Each chapter includes the project’s overviews and objectives, the particular challenges they are covering, research achievements on security and privacy, as well as the techniques, outcomes, and evaluations accomplished in the scope of the EU project. The book is the result of a collaborative effort among relative ongoing European Research projects in the field of privacy and security as well as related cybersecurity fields, and it is intended to explain how these projects meet the main cybersecurity and privacy challenges faced in Europe. Namely, the EU projects analyzed in the book are: ANASTACIA, SAINT, YAKSHA, FORTIKA, CYBECO, SISSDEN, CIPSEC, CS-AWARE. RED-Alert, Truessec.eu. ARIES, LIGHTest, CREDENTIAL, FutureTrust, LEPS. Challenges in Cybersecurity and Privacy - the European Research Landscape is ideal for personnel in computer/communication industries as well as academic staff and master/research students in computer science and communications networks interested in learning about cyber-security and privacy aspects

    18th SC@RUG 2020 proceedings 2020-2021

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